Fermentations

Appl Environ Microbiol, 1995 Oct, 61(10), 3521 - 9
Genetic diversity and geographical distribution of wild Saccharomyces cerevisiae strains from the wine-producing area of Charentes, France; Versavaud A et al.; Electrophoretic karyotyping, mitochondrial DNA restriction fragment length polymorphism analysis, and PCR amplification of interspersed repeats were used to study the variability, phylogenetic affinities, and biogeographic distribution of wild Saccharomyces cerevisiae enological yeasts . The survey concentrated on 42 individual wine cellars in the Charentes area (Cognac region, France) . A limited number (35) of predominant S . cerevisiae strains responsible for the fermentation process have been identified by the above molecular methods of differentiation . One strain (ACI) was found to be distributed over the entire area surveyed . There seemed to be little correlation between geographic location and genetic affinity.

Appl Biochem Biotechnol, 1995 Oct, 55(1), 5 - 15
Production of human insulin in an E . coli system with Met-Lys-human proinsulin as the expressed precursor; Chen JQ et al.; The construction of a gene encoding Lys-human proinsulin, its direct expression in E . coli, and the simple purification procedure are described here . The temperature inducible promotor was employed for induction in a very short time . The expression level could reach 20-30% . After simple downstream processing and only one step of Sephadex G50 purification, 150 mg recombinant Lys-human proinsulin with a purity of up to 90% could be obtained easily from 1 L of high density fermentation medium . The obtained product is in the form of Met-Lys-human proinsulin because of the failure of the bacterial host to remove the initiator methionine residue . The Lys-human proinsulin could be changed into human insulin by trypsin and carboxypeptidase B treatment in later steps . After separation with DEAE-Sephadex A25, human insulin with expected amino acid composition and full native biological activity could be obtained with a yield of 50 mg/L of fermentation medium.

J Biol Chem, 1995 Sep 22, 270(38), 22321 - 8
Role of the evolutionarily conserved cytochrome b tryptophan 142 in the ubiquinol oxidation catalyzed by the bc1 complex in the yeast Saccharomyces cerevisiae; Bruel C et al.; Trp-142 is a highly conserved residue of the cytochrome b subunit in the bc1 complexes . To study the importance of this residue in the quinol oxidation catalyzed by the bc1 complex, we characterized four yeast mutants with arginine, lysine, threonine, and serine at position 142 . The mutant W142R was isolated previously as a respiration-deficient mutant unable to grow on non-fermentable carbon sources (Lemesle-Meunier, D., Brivet-Chevillotte, P., di Rago, J.-P, Slonimski, P.P., Bruel, C., Tron, T., and Forget, N . (1993) J . Biol . Chem . 268, 15626-15632) . The mutants W142K, W142T, and W142S were obtained here as respiration-sufficient revertants from mutant W142R . Mutant W142R exhibited a decreased complex II turnover both in the presence and absence of antimycin A; this suggests that the structural effect of W142R in the bc1 complex probably interferes with the correct assembly of the succinate-ubiquinone reductase complex . The mutations resulted in a parallel decrease in turnover number and apparent Km, with the result that there was no significant change in the second-order rate constant for ubiquinol oxidation . Mutants W142K and W142T exhibited some resistance toward myxothiazol, whereas mutant W142R showed increased sensitivity . The cytochrome cc1 reduction kinetics were found to be severely affected in mutants W142R, W142K, and W142T . The respiratory activities and the amounts of reduced cytochrome b measured during steady state suggest that the W142S mutation also modified the quinol-cytochrome c1 electron transfer pathway . The cytochrome b reduction kinetics through center P were affected when Trp-142 was replaced with arginine or lysine, but not when it was replaced with threonine or serine . Of the four amino acids tested at position 142, only arginine resulted in a decrease in cytochrome b reduction through center N . These findings are discussed in terms of the structure and function of the quinol oxidation site and seem to indicate that Trp-142 is not critical to the kinetic interaction of ubiquinol with the reductase, but plays an important role in the electron transfer reactions that intervene between ubiquinol oxidation and cytochrome c1 reduction.

Fiziol Zh, 1995 Sep-Dec, 41(5-6), 44 - 9
{The characteristics of tissue lipid peroxidation in the internal organs and the lipid metabolic indices of the blood plasma in a low geomagnetic field}; Babych VI; It was found in experiments on guinea-pigs and white rats that 100-time weakened magnetic field of the earth considerably increased the activity of peroxide oxidation of lipids (POL) in tissues of inner organs . In the lungs, liver, kidneys, small intestine under the influence of hypogeomagnetic field (HGMF) we have observed reduction of ferment antioxidizing activity and of non-ferment mechanisms in the heart . The process is accompanied by reduction of cholesterol, phospholipids and triglycerides in guinea-pigs and increase of this indices in white rats after 5-day-long stay of animals in the hypogeomagnetic chamber . The data of experiments on white rats underlie a conclusion that the 5-day-long influence of HGMF promotes the change of the carbohydrate metabolism for lipid metabolism . The reaction of guinea-pigs on the stay under the weakened magnetic field of the earth displays in reduction of the level of lipid metabolism indices in the blood serum.

Plant Foods Hum Nutr, 1995 Sep, 48(2), 113 - 7
Effect of processing on nutrient composition and anti-nutritive substances of African locust bean (Parkia filicoidea) and baobab seed (Adansonia digitata); Addy EO et al.; The effects of various processing techniques on nutrient composition and anti-nutritional factors in baobab seeds (Adansonia digitata L.) and locust beans (Parkia filicoidea L.) were investigated . The methods used for processing include boiling in water, acid or alkali and fermentation . Using the water treated samples as controls, there were slight decreases in protein and carbohydrate contents of the fermented and alkali-treated meals . However, an increase in extractable oil content was observed in acid, alkali and fermented samples . The alkali treatment appeared to be the most effective method for reducing trypsin inhibitor and tannin contents and has the additional advantage of improving the protein digestibility.

Nutrition, 1995 Sep-Oct, 11(5 Suppl), 568 - 72
Effects of bio-normalizer (a food supplementation) on free radical production by human blood neutrophils, erythrocytes, and rat peritoneal macrophages; Osato JA et al.; Bio-normalizer, a natural Japanese health food prepared by the fermentation of Carica papaya, exhibits therapeutic properties against various pathologies including tumors and immunodeficiency . To understand the mechanism of bio-normalizer's therapeutic effects, we studied its action on the production of active oxygen species in cell-free systems (the Fenton reaction, the xanthine-xanthine oxidase system, and the hydrogen peroxide-hypochloride or hydrogen peroxide-horseradish peroxidase systems) and by human blood neutrophils and erythrocytes and rat peritoneal macrophages . Bio-normalizer efficiently inhibited the formation of oxygen radicals in cell-free systems and partly decreased spontaneous and menadione-stimulated superoxide production by erythrocytes, but manifested both stimulatory and inhibitory effects on oxygen radical release by dormant and activated phagocytes (neutrophils and macrophages) . We suggest that bio-normalizer is able to enhance the intracellular production of innocuous superoxide ion and, at the same time, to diminish the formation of reactive hydroxyl radicals, perhaps by the inactivation of ferrous ions, the catalysts of the superoxide-driven Fenton reaction . We also propose that the normalization of an organism's superoxide level is one of the molecular mechanisms of bio-normalizer activity.

Mol Microbiol, 1995 Sep, 17(6), 1093 - 107
Characterization of AGT1 encoding a general alpha-glucoside transporter from Saccharomyces; Han EK et al.; Molecular genetic analysis is used to characterize the AGT1 gene encoding an alpha-glucoside transporter . AGT1 is found in many Saccharomyces cerevisiae laboratory strains and maps to a naturally occurring, partially functional allele of the MAL1 locus . Agt1p is a highly hydrophobic, postulated integral membrane protein . It is 57% identical to Mal61p, the maltose permease encoded at MAL6, and is also a member of the 12 transmembrane domain superfamily of sugar transporters . Like Mal61p, Agt1p is a high-affinity, maltose/proton symporter, but Mal61p is capable of transporting only maltose and turanose, while Agt1p transports these two alpha-glucosides as well as several others including isomaltose, alpha-methylglucoside, maltotriose, palatinose, trehalose and melezitose . AGT1 expression is maltose inducible and induction is mediated by the Mal-activator . The sequence of the upstream region of AGT1 is identical to that of the maltose-inducible MAL61 gene over a 469 bp region containing the UASMAL but the 315 bp sequence immediately upstream of AGT1 shows no significant homology to the sequence immediately upstream of MAL61 . The evolutionary origin of the MAL1 allele to which AGT1 maps and the relationship of AGT1 to other alpha-glucoside fermentation genes is discussed.

Rev Sci Tech, 1995 Sep, 14(3), 865 - 71
Characterisation of mycoplasmas isolated from genital tract infections of sheep in Nigeria; Chima JC et al.; Four mycoplasma-like organisms isolated from ewes with mucopurulent vaginal discharge and swollen vulva were characterised . Biochemical tests showed three of the isolates to be negative for glucose fermentation and arginine hydrolysis, while the remaining isolate was negative for glucose fermentation but hydrolysed arginine . Serological identification using the growth inhibition, growth precipitation and indirect immunofluorescence tests indicated the three similar isolates as Mycoplasma bovigenitalium and the other isolate as Mycoplasma arginini . There are apparently no previous reports of the isolation of these organisms from the genital tract of sheep in Nigeria.

Br Poult Sci, 1995 Sep, 36(4), 611 - 29
Contribution of oligosaccharide and polysaccharide digestion, and excreta losses of lactic acid and short chain fatty acids, to dietary metabolisable energy values in broiler chickens and adult cockerels; Carre B et al.; 1 . Two experiments were conducted, using both adult cockerels from a layer strain and 3-week-old broiler chickens . In the first experiment, one of the 2 diets investigated was composed mainly of maize and soyabean meals, the other one containing the latter ingredients diluted with 475 g/kg mature pea seeds . For these 2 diets, the apparent metabolisable energy values corrected to 0 nitrogen retention (AMEn) were derived, together with the apparent digestibilities of nitrogen, amino acids, total lipids, starch, individual oligosaccharides, and non-starch polysaccharides (NSP) . Excretions of lactic acid and short chain fatty acids (SCFA) were also determined . 2 . In the first experiment, the mean apparent digestibilities of starch, lipids, total amino acids, NSP, sucrose and alpha-galacto-oligosaccharides in adult cockerels were 0.946, 0.785, 0.835, 0.045, 0.99 and 0.99, respectively . In broiler chickens, they were 0.938, 0.675, 0.830, -0.016, 0.988 and 0.867, respectively . The bird type effects were significant (P < 0.05) for the digestibilities of starch, lipids, NSP (for the maize-soyabean meal diet, only) and alpha-galacto-oligosaccharides . Broiler chickens excreted a mean of 11.032 g organic acids/kg diet against 4.190 in adult cockerels (P < 0.001) . These digestibility measurements enabled the contribution made by each dietary component to the AMEn value of the diets to be calculated . AMEn values were lower in broiler chickens than in adult cockerels, with on average 0.8 MJ/kg dry matter difference resulting from bird type . This difference was accounted for by differences between bird types in energy supplied by lipids (34.0%), starch (7.5%), alpha-galacto-oligosaccharides (8.7%), NSP (14.2%), and in energy losses from lactic acid excretion (16.4% of the difference in AMEn between bird types) . 3 . In the second experiment 2 diets were studied, consisting of a basal and the basal diluted with 30 g/kg lactose (a fermentable sugar in chickens) and 12 g/kg of a water-soluble gel-forming component containing 50% polygalacturonic acids . Lactose digestibilities reached 0.928 and 0.712 in adult cockerels and chickens, respectively . The digestibilities of the water-soluble polygalacturonic acids were similar in cockerels and broiler chickens, with a mean value of 0.672 . Figures similar to those of the first experiment were found in the comparison between cockerels and broiler chickens, for the AMEn values of diets, the digestibilities of starch and lipids and the excretion of lactic acid . Broiler chickens excreted 4.580 g lactic acid/kg dry food intake, compared with 0.740 g in the adult.(ABSTRACT TRUNCATED AT 400 WORDS)

J Anim Sci, 1995 Sep, 73(9), 2820 - 33
Impact of changes in organic nutrient metabolism on feeding the transition dairy cow; Grummer RR; Pregnancy, decreased feed intake during late gestation, lactogenesis, and parturition have dramatic effects on metabolism in dairy cows during the transition period from 3 wk before calving to 3 wk after calving . Increases in plasma NEFA occur during the 10 d before calving and may precede the decrease in feed intake . Plasma NEFA concentrations are highest at calving and decrease rapidly after calving . Plasma glucose concentration decreases during the transition period except for a transient increase associated with calving . Hepatic glycogen is reduced and lipid is increased during the transition period . Feed intake is usually decreased 30 to 35% during the final 3 wk prepartum, but negative energy and protein balances are not as severe as during the week following parturition . Prepartum feed intake is positively correlated to postpartum feed intake; therefore, efforts to maximize feed intake should begin before calving . Overconditioned cows may be more susceptible to a prepartum decrease in feed intake . Increasing nutrient density of the diet during the transition period may enhance feed intake . Feeding more fermentable carbohydrate during the prepartum transition period may acclimate the microbial population to lactation diets, promote development of ruminal papillae, increase absorptive capacity of the rumen epithelium, and reduce lipolysis by delivering more glucogenic precursor to the liver and enhancing blood insulin . Supplementing fat to transition diets does not seem to alleviate health problems associated with negative energy balance . Enhancing amino acid absorption by the prepartum cow may improve lactation performance and health, although mechanisms of action have not been identified.

J Anim Sci, 1995 Sep, 73(9), 2791 - 803
Feeding behavior and management factors during the transition period in dairy cattle; Grant RJ et al.; Little research has focused specifically on the relationships among feeding behavior, management strategy, and optimal intake by the transition cow . Most information must be extrapolated from studies of cattle at other stages of lactation . The transition period can be divided into two distinct phases: 5 to 7 d prepartum, characterized by a 30% reduction in DMI, and 0 to 21 d postpartum, during which time intake should increase rapidly . Feed restriction can reduce number of daily meals by 50%, but when feed is offered for ad libitum consumption, with consistent time of feeding, access can be limited to 8 h daily with no adverse effects on performance of midlactation cows . Sequence of offering feeds may affect intake, but relative degradabilities of dietary protein and starch need to be considered . During early lactation, increased feeding frequency of a total mixed diet may most improve intake when dietary fermentability is moderate to high and management quality is poor . High-producing dairy cows achieve greater intake by increasing meal size and spending less time eating and ruminating per unit of intake . Control of feed intake and meal patterns may differ by parity and should be considered when grouping cattle . Daily exercise of tied dairy cows may not affect intake . Grouping strategy and group feeding behavior influence cow productivity and profitability . Competition for feed and space can be reduced by fenceline feeding vs bunks . Optimum intake during the transition period will occur only if feeding management accommodates normal feeding behavior of dairy cows.

J Anim Sci, 1995 Sep, 73(9), 2677 - 86
Influence of forage level and naloxone injection on feed intake, digestion, and plasma hormone and metabolite concentrations in dairy heifers; Burgwald-Balstad LA et al.; Four ruminally cannulated Holstein heifers (287 +/- 26 kg) in a 4 x 4 Latin square were used to evaluate the effects of naloxone injection and forage level on dietary intake, ruminal fermentation characteristics, digestibility, and plasma hormone and metabolite concentrations . Treatments were arranged in a 2 x 2 factorial with naloxone injection (0 vs .3 mg/kg; saline vs naloxone, respectively) and forage level (20 vs 100%; concentrate vs forage) as factors . Stanchioned heifers were allowed 21 d for adaptation before a 5-d collection period . Plasma samples were collected several times on d 1 and daily at 0730 . Concentrate-fed heifers consumed more feed (P < .10) than forage-fed heifers . Naloxone injection decreased (P < .10) feed intake (grams/kilogram BW) at 1 and 2 h after feeding on d 1 . On d 3 at 24 h after feeding, naloxone-injected heifers had increased DM (P < .10) intakes compared with control (saline-injected) heifers . Concentrate-fed heifers had decreased (P < .10) ruminal pH and increased total ruminal VFA concentration . Acetate proportion was decreased (P < .10) and propionate proportion increased in concentrate-fed heifers . Naloxone-injected heifers had decreased (P < .10) total VFA concentrations and increased propionate proportions . Concentrate-fed heifers had greater (P < .10) DM, OM, and CP digestibilities as well as increased plasma (P < .10) insulin, urea N, and glucose concentrations but decreased (P < .10) GH and NEFA concentrations . Naloxone injection increased (P < .10) plasma insulin concentration . Naloxone injection in dairy heifers reduces intake up to 2 h after injection, alters ruminal fermentation patterns, and increases plasma insulin concentration.

Lipids, 1995 Sep, 30(9), 847 - 53
Resistant starch is more effective than cholestyramine as a lipid-lowering agent in the rat; Younes H et al.; Amylase-resistant starch (RS) represents a substrate for the bacterial flora of the colon, and the question arises as whether RS shares with soluble fibers common mechanisms for their lipid-lowering effects . It is uncertain whether a cholesterol-lowering effect depends basically on an enhanced rate of steroid excretion or whether colonic fermentations also play a role in this effect . In the present study, the effect of RS (25% raw potato starch), of a steroid sequestrant (0.8% cholestyramine), or both were compared on bile acid excretion and lipid metabolism in rats fed semipurified diets . RS diets led to a marked rise in cecal size and the cecal pool of short-chain fatty acids (SCFA), as well as SCFA absorption; cholestyramine did not noticeably affect cecal fermentation . Whereas cholestyramine was particularly effective at enhancing bile acid excretion, RS was more effective in lowering plasma cholesterol (-32%) and triglycerides (-29%) . The activity of 3-hydroxy-3-methylglutaryl-CoA reductase was increased fivefold by cholestyramine and twofold by RS . This induction in rats fed RS diets was concomittant to a depressed fatty acid synthase activity . In rats fed the RS diet, there was a lower concentration of cholesterol in all lipoprotein fractions, especially the (d = 1.040-1.080) fraction high-density lipoprotein (HDL1), while those fed cholestyramine had only a significant reduction of HDL1 cholesterol . In contrast to cholestyramine, RS also depressed the concentration of triglycerides in the triglyceride-rich lipoprotein fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Crit Rev Food Sci Nutr, 1995 Sep, 35(5), 431 - 53
Value-added products from underutilized fish species; Venugopal V et al.; Fish is a rich source of easily digestible protein that also provides polyunsaturated fatty acids, vitamins, and minerals for human nutrition . Nonetheless, a large proportion of total landed fish remains unused due to inherent problems related to unattractive color, flavor, texture, small size, and high fat content . Most of these underutilized fish belong to the abundantly available pelagic species, which are landed as bycatch, and some are unconventional species such as krill . Although some species are used industrially for fish meal manufacture, a need for their conservation and utilization for human consumption has been recognized in order to prevent post-harvest fishery losses . Recovery of flesh by mechanical deboning and development of value-added products are probably the most promising approaches . This article discusses various possibilities for product development using mince from low-cost fishery resources . These include surimi and surimi-based products, sausages, fermented products, protein concentrates and hydrolysates, extruded products, and biotechnological possibilities . The dual advantages of this approach, namely, finding ways for better utilization of low-value fish species and providing protein- rich convenience foods, have been pointed out . However, the key to the success of this approach depends largely on the market strategies utilized.

J Dairy Sci, 1995 Sep, 78(9), 1999 - 2007
Effects of ruminal versus duodenal dosing of fish meal on ruminal fermentation and milk composition; Calsamiglia S et al.; Three midlactation Holstein cows with ruminal and duodenal cannulas were used in a 3 x 3 Latin square design to determine whether ruminal or postruminal alterations in metabolism were responsible for the changes in milk composition that frequently are associated with dietary fish meal . Cows were offered a diet of 60:40 forage to concentrate (aliquots at 6-h intervals) that was supplemented with isonitrogenous amounts of soybean meal (1.3 kg of DM/d) dosed into the rumen or fish meal (1.0 kg DM/d) dosed either into the rumen or into the duodenum . The DMI, ruminal NDF digestion, and flows of total N and microbial N to the duodenum decreased for cows receiving fish meal . Dietary N flow increased when fish meal was dosed into the rumen . Total concentration of ruminal VFA was greater for cows receiving the soybean meal treatment; however, treatment had no effect on the ratio of ruminal acetate plus butyrate to propionate . Milk and FCM yields were unaffected by treatment, but milk fat content decreased, and milk protein content increased when cows were supplemented with fish meal . The difference in mammary arteriovenous glucose difference decreased when cows were dosed with fish meal . Changes in plasma NEFA and triglycerides were small and inconsistent . Results from this experiment suggest that effects of fish meal on milk composition are due to postruminal alterations in metabolism.

J Dairy Sci, 1995 Sep, 78(9), 1981 - 98
Ruminal fermentation and passage of nutrients to the duodenum of lactating cows fed mixtures of corn and barley; Overton TR et al.; Five Holstein cows were used in a 5 x 5 Latin square design and fed diets containing five different ratios of starch from ground shelled corn and steam-rolled barley . The DMI decreased and both the proportions of OM and starch digested in the rumen increased as barley starch increased in the diet . Corn and barley starches fed in a ratio of 75:25 maximized the proportions of ADF and NDF digested in the rumen . Replacement of 25% of the corn starch with barley starch resulted in the largest increase in the molar percentage of propionate and the largest decrease in the molar percentage of acetate in ruminal fluid . Passage of NAN to the duodenum was not affected by treatment; however, the percentage of nonammonia nonmicrobial N in NAN decreased as barley starch increased . Passage of AA to the duodenum was largest when corn and barley starches were fed in ratios of 100: 0 and 0:100 because of the influence of DMI and microbial protein synthesis . Production of Milk, CP, and SNF was similar when cows were fed diets containing corn and barley starches in ratios of 100:0, 75:25, and 50:50 but was decreased when the ratios were 25:75 and 0:100 . Increased production responses of cows when diets contained larger amounts of starch from ground shelled corn were probably due to increased DMI.

Biotechnol Prog, 1995 Sep-Oct, 11(5), 558 - 64
Mathematical model for analysis of mass transfer for immobilized cells in lactic acid fermentation; Wang H et al.; A new mathematical model is proposed to analyze the mass transfer behavior in lactic acid fermentation using immobilized cells entrapped in calcium alginate . The model is comprised of material balance equations for glucose, free lactic acid, and several ions . The dissociation rate of lactic acid (rdiss) is involved in the proposed equations . To solve the equations numerically, a modified calculating method is proposed . Through model analysis, the possible mass transfer behavior in the gel bead was discussed . The model is validated by comparisons with the experimental results obtained from batch and continuous fermentation . The simulations using the model were made to investigate the mass transfer limitation in the gel beads . The results showed that the cell density gradient was formed in the gel beads and it was caused by the accumulation of the inhibitory product (free lactic acid), not by substrate starvation . Moreover, unusual mass transfer behavior of lactate ion in the immobilization support was pointed out.

Int J Pept Protein Res, 1995 Sep-Oct, 46(3-4), 205 - 8
Novel microbial inhibitors of ACE . Isolation and characterization; Bauer K et al.; Two novel microbial ACE-inhibitors BAY o 6997 and BAY q 1313 were detected in the fermentation broths of streptomyces spec . WS 464 and spec . WS 1065, respectively . Both were isolated and purified by ion exchange chromatography as initial steps, and final purification was achieved by HPLC or additional chromatography of the Cu-chelate (BAY q 1313) . Both inhibitors are reversibly inactivated on chelation with Cu2+ or Zn2+ . Irreversible inactivation occurs on standing in aqueous and acidic solution or in ammonium hydroxide at room temperature and more rapidly on heating . In 4 M sodium hydroxide solutions BAY o 6997 is completely stable, and BAY q 1313 still remarkably stable even on longer heating to 80 degrees C . Thus, BAY o 6997 was alternatively and advantageously isolated after heating of its solution in 4 M sodium hydroxide to 37 degrees C for 2 days and subsequent fractional precipitation with ethanol in a relatively pure state . Total hydrolysis yielded His, 2-methylamino-4-amino-butyric acid and alpha-keto butyric acid (BAY o 6997) and pyruvic acid (BAY q 1313) respectively . The unusual stability of both inhibitors in sodium hydroxide solution on the one hand and their instability on heating and storage in aqueous or acidic solutions on the other hand clearly prove that the constituents are not linked by amide bonds.

Nippon Yakurigaku Zasshi, 1995 Sep, 106(3), 193 - 204
{Discovery and pharmacological properties of selective neurokinin-receptor antagonists, FK224 and FK888}; Fujii T; In order to create a new drug for the treatment of respiratory diseases, such as asthma and chronic bronchitis, having a novel therapeutic mechanism, we have been trying to develop new compounds with neurokinin (NK)-receptor antagonistic effects . We used {3H}-substance P binding to guinea pig lung membrane for the first screening system and successfully discovered FK224 from a fermentation product and FK888 from chemical design studies using an octapeptide antagonist (D-Pro4,D-Trp7,9,10) SP4-11 as the parent compound . FK224 and FK888 showed different selectivities against the NK-receptor subtypes (NK1, NK2, NK3); FK888 was a highly potent NK1-selective antagonist, and FK224 was a NK1 + NK2 dual receptor antagonist . Neither compound had any activity on the NK3 receptor . In the in vivo experiments, FK224 and FK888 significantly inhibited the constriction and plasma extravasation in the airway induced by agonist injection . These compounds also showed inhibitory effects on the airway response induced by capsaicin and antidromic stimulation of vagus nerves . Furthermore, FK224 and FK888 were effective on the mucus secretion in the airway and the cough reflex induced by citric acid challenge . There were some differences in the effects of FK224 and FK888 in the in vivo experiments, and it was suggested that the NK1 receptor and NK2 receptor were mainly involved in neurogenic inflammation and airway constriction, respectively . FK224 and FK888 are now undergoing clinical studies to test the effectiveness of a NK antagonist in human respiratory diseases.

Br J Biomed Sci, 1995 Sep, 52(3), 173 - 7
Biotyping of Escherichia coli in microwell plates; Crichton PB et al.; A simple, inexpensive scheme of eight tests for biotyping strains of Escherichia coli in microwell plates is described . The tests comprise primary tests for the fermentation of raffinose, sorbose, ornithine, dulcitol and 2-deoxy-D-ribose, and secondary tests for rhamnose fermentation, lysine decarboxylation and motility . Among a collection of 75 clinical isolates of Esch . coli from 12 patients, 18 full biotypes designated according to their positive and negative reactions in the eight tests were distinguished . These biotypes gave an indication of the natural history of patients' infections . Because it provides excellent and reliable type discrimination, biotyping can be used in a combination with other typing techniques to resolve local epidemiological problems involving Esch . coli.

Zh Mikrobiol Epidemiol Immunobiol, 1995 Sep-Oct, (5), 3 - 8
{The characteristics of new species of pathogenic microorganisms in the genus Francisella}; Meshcheriakova IS et al.; The comparative study of newly discovered pathogenic bacteria of the genus Francisella was carried out with the use of a complex of microbiological and serological methods . While having great similarity to the causative agent of tularemia, F . novicida, F . novicida-like bacteria and F . philomiragia had lesser growth requirements, some specific morphological and structural features, were capable of fermenting sucrose and exhibited low pathogenicity to experimental animals . The strains under study proved to be virulent with regard to golden hamsters, who were for this reason proposed as an adequate model for the isolation of these bacteria from environmental objects and pathological material obtained from patients . The use of immunoblotting made it possible to find out that all Francisella species had protein antigens, similar to their electrophoretic mobility and serological activity.

Nutr Hosp, 1995 Sep-Oct, 10(5), 279 - 85
{Cytometric study of colonic tumors in a model of experimental colonic cancer . Impact of the diet}; Afonso Rodriguez JJ et al.; Butyrate is a short chain fatty acid, made up of four carbon atoms . Along with acetate and propionate, they are the main volatile fatty acids formed by the microbial fermentation of the carbohydrates of dietary fibre in the colon, mainly in the caecum . Additionally, they acidify the intracolonic pH, and they play an important role in the regulation of the absorption of water and sodium . On the other hand, they are, especially butyrate, preferred by the colon cell, as sources of energy alternative to glucose . Besides this, butyrate, in cellular cultures, is a known antineoplasic agent which is characterized by doubling the cellular duplication time for cells in the G1 phase, it increases the activity of certain enzymes, it stimulates the effects of interferon, it modifies the morphology of the cells, which in some cases leads to the reversion of the characteristic transformations of the cancerous cells, and it produces alterations in the chromatin, the nucleoli, elements of the cytoskeleton and the Golgi apparatus . Even though it is not known how it causes these actions, it is thought that the acetylization of histones which it produces, may be an important mechanism . We analyzed the effect of this substance in a colonic carcinogenesis model in Sprague-Dawley rats, in which the tumors were induced with the alkylating agent 1,2-dimethylhydrazide, observing the cytometric pattern of the tumors, and the possible differences between both groups . In one of them, sodium butyrate was continuously infused by means of a intrathecal catheter at a rhythm of 1.5 ml/hour during the tumoral induction which lasted four weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Am J Gastroenterol, 1995 Sep, 90(9), 1455 - 60
Factors influencing the 1-g 14C-D-xylose breath test for bacterial overgrowth; Riordan SM et al.; OBJECTIVES: To document the sensitivity of the 1-g 14C-D-xylose breath test for bacterial overgrowth and to investigate luminal and nonluminal factors that may influence breath 14CO2 levels and impact on the clinical utility of this test . METHODS: Thirty-five adult subjects were investigated for bacterial overgrowth by culture of gastric and small intestinal aspirates and by a 1-g 14C-D-xylose breath test . Body weight, gastroduodenal pH and the in vitro capability of overgrowth flora to ferment D-xylose were assessed . Serial breath 14CO2 levels were also recorded before and after the resolution of malabsorption in a subject with celiac disease to determine the importance of postabsorptive metabolism of this substrate . RESULTS: Gastric and small intestinal bacterial overgrowth were present in 19/35 (54.3%) and 21/35 (60.0%) subjects, respectively . The positivity rate of culture of aspirate exceeded that of the 1-g 14C-D-xylose breath test . Endogenous CO2 production independently influenced breath 14CO2 levels . After excluding this influence, sensitivity of the 1-g 14C-D-xylose breath test for gastric bacterial overgrowth or small intestinal bacterial overgrowth was poor, even when overgrowth with specific "marker organisms" was considered . Poor sensitivity could not be explained by unfavorable luminal pH . Overgrowth flora were proven capable of in vitro D-xylose fermentation in 81.8% of subjects . Systemic and/or colonic metabolism of 1-g 14C-D-xylose appear to be important factors influencing results of the 1-g 14C-D-xylose breath test, especially in partial gastrectomy subjects . CONCLUSIONS: The 1-g 14C-D-xylose breath test is not a suitable alternative to culture of aspirate for the investigation of subjects for bacterial overgrowth.

J Antibiot (Tokyo), 1995 Sep, 48(9), 990 - 6
Structure of the new spiroketal-macrolide A82548A; Kirst HA et al.; A new member of the spiroketal-containing macrolide class of fermentation-derived natural products was isolated from mycelial extracts of Streptomyces diastatochromogenes . The principal component, A82548A, was shown to possess a 22-membered macrolide ring system onto which was incorporated both a spiroketal and a hemiketal moiety . Relative stereochemistry was established by single crystal X-ray diffraction studies . Absolute stereochemistry was determined via hydrolysis of the amino sugar glycosidically linked to the aglycone, which was identified as L-kedarosamine . The overall three-dimensional structure is closely related to that of the macrolides cytovaricin, rutamycin, and ossamycin.

J Antibiot (Tokyo), 1995 Sep, 48(9), 973 - 6
Ratjadon: a new antifungal compound from Sorangium cellulosum (myxobacteria) production, physio-chemical and biological properties; Gerth K et al.; An antifungal activity, ratjadon, was detected in the culture broth of Sorangium cellulosum (Myxococcales) strain So ce360 . The metabolite was quantitatively bound to the adsorber resin XAD-16, which was added to the medium at the beginning of the fermentation . The antibiotic spectrum was narrow, but some important phytopathogenic fungi, especially species of Oomycetes, were inhibited at very low concentrations.

J Antibiot (Tokyo), 1995 Sep, 48(9), 937 - 41
Amidepsines, inhibitors of diacylglycerol acyltransferase produced by Humicola sp . FO-2942 . I . Production, isolation and biological properties; Tomoda H et al.; Humicola sp . FO-2942, a soil isolate, was found to produce a series of new inhibitors of diacylglycerol acyltransferase (DGAT) . Three active compounds, designated amidepsines A, B and C, were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography, ODS column chromatography and HPLC . Amidepsines inhibit DGAT activity with IC50 values of 10.2 approximately 51.6 microM in an enzyme assay system using rat liver microsomes . Amidepsines also showed specific inhibition of triacylglycerol formation in intact Raji cells, indicating that they inhibit DGAT activity in living cells.

J Antibiot (Tokyo), 1995 Sep, 48(9), 913 - 23
Azaphilones with endothelin receptor binding activity produced by Penicillium sclerotiorum: taxonomy, fermentation, isolation, structure elucidation and biological activity; Pairet L et al.; A series of azaphilones produced by Penicillium sclerotiorum (Xenova culture collection number X11853) active in assays for the detection of antagonists of the endothelin-A (ETA) and endothelin-B (ETB) receptors has been identified . The series includes two novel sclerotiorin analogues, (8S,8 alpha-R)-7-deacetyl-1,O8,8,8a-tetrahydro-7-epi-sclerotiorin, 1, and its 5-dechloro analogue, 2 . It also includes 5-chloroisorotiorin, 6, previously unreported as a natural product, in addition to the major product of these fermentations, (+)-sclerotiorin, 5 . Data for the inhibition of endothelin-1 (ET-1) and endothelin-3 (ET-3) binding in the ETA and ETB receptor assays respectively are reported for this series . Compounds 1 and 2 were more selective for the rabbit ETA receptor than for the rat ETB receptor . The IC50 values for 1 and 2 were 9 and 28 microM respectively in an assay based on binding of ET-1 to rabbit ETA receptors . In an assay based on the binding of ET-3 to the rat ETB receptor compounds 1 and 2 exhibited IC50's of 77 and 172 microM . Members of this series of compounds demonstrated antagonist behavior in a secondary assay based on blockade of ET-1 stimulated arachidonic acid release from rabbit renal artery smooth muscle cells, when present at concentrations of > or = 30 microM.

Appl Environ Microbiol, 1995 Sep, 61(9), 3293 - 8
Isolation and characterization of an anaerobic ruminal bacterium capable of degrading hydrolyzable tannins; Nelson KE et al.; An anaerobic diplococcoid bacterium able to degrade hydrolyzable tannins was isolated from the ruminal fluid of a goat fed desmodium (Desmodium ovalifolium), a tropical legume which contains levels as high as 17% condensed tannins . This strain grew under anaerobic conditions in the presence of up to 30 g of tannic acid per liter and tolerated a range of phenolic monomers, including gallic, ferulic, and p-coumaric acids . The predominant fermentation product from tannic acid breakdown was pyrogallol, as detected by high-performance liquid chromatography and mass spectrometry . Tannic acid degradation was dependent on the presence of a sugar such as glucose, fructose, arabinose, sucrose, galactose, cellobiose, or soluble starch as an added carbon and energy source . The strain also demonstrated resistance to condensed tannins up to a level of 4 g/liter.

Br J Nutr, 1995 Sep, 74(3), 303 - 22
Estimation of the fermentability of dietary fibre in vitro: a European interlaboratory study; Barry JL et al.; Five European laboratories tested a simple in vitro batch system for dietary fibre fermentation studies . The inoculum was composed of fresh human faeces mixed with a carbonate-phosphate buffer complex supplemented with trace elements and urea . Five dietary fibre sources (cellulose, sugarbeet fibre, soyabean fibre, maize bran and pectin) were used by each laboratory on three occasions to determine pH, residual non-starch polysaccharides (NSP) and short-chain fatty acid production during fermentation . Cellulose and maize bran degradabilities were very low (7.2(SE 10.8) and 6.2 (SE 9.1)% respectively after 24 h), whereas pectin and soyabean fibre were highly degraded (97.4 (SE 4.4) and 91.1 (SE 3.4)% respectively after 24 h) . Sugarbeet fibre exhibited an intermediate level of degradability (59.5 (SE 14.9)%) . Short-chain fatty acid production was closely related to NSP degradation (r 0.99) . Although each variable was ranked similarly by all laboratories, some differences occurred with respect to absolute values . However, the adaptation of donors to the experimental substrates was not an influential factor . Interlaboratory differences could be reduced either by adding less substrate during incubations or using less-diluted inocula . In vitro fermentations with inocula made from human faeces and from rat caecal contents gave similar results . There was a close correspondence between the data obtained in the present experiment and those previously published in in vivo studies in the rat using the same fibres . The in vitro batch system tested during the present study provides a rapid means of obtaining quantitative estimates of the fermentation and the estimation of the energy content of new sources of dietary fibre.

Br J Nutr, 1995 Sep, 74(3), 289 - 302
Determination of digestible energy values and fermentabilities of dietary fibre supplements: a European interlaboratory study in vivo; Livesey G et al.; The performance of methods to determine energy conversion factors for dietary fibre (DF) supplements and fermentability (D) values of their non-starch polysaccharides (NSP) was investigated . Heats of combustion, digestible energy (DE) and D values were determined on five DF supplements in five European laboratories on five separate occasions . In each instance the DF supplements were fed to juvenile male Wistar rats at two doses, 50 and 100 g/kg basal diet, for 3 weeks with food and faeces collected in the 3rd week . Among-laboratory variations in heats of combustion (delta Hc) were < 2% . DE values (kJ/g dry weight) at the upper and lower doses respectively were: 10.4 and 9.9 for a high-methoxyl apple pectin, 9.5 and 9.4 for a sugar-beet DF supplement, 12.2 and 12.7 for soyabean DF supplement, 3.8 and 4.0 for maize bran, and 0.3 and 0.3 for Solka-floc cellulose . Variations among laboratories, among occasions and among animals were < 1, < 2 and < 2.5 kJ/g respectively . The among-occasion: among-laboratory variance ratio for DE was 0.5, suggesting the method performed equally well in all laboratories . There was no evidence of learning of fatigue or fatigue in the performance of the method . D values were also independent of dose and at the high and lower doses were: pectin 0.92 and 0.95, sugar-beet NSP 0.68 and 0.68, soyabean NSP 0.86 and 0.88, maize bran 0.17 and 0.18, cellulose 0.07 and 0.06 . Among-laboratory variance tended to increase with decreasing fermentability and ranged from 0.03 to 0.18 . The DE and D data were not significantly different from a previously proposed relationship DE = 0.7 x delta Hc x D, where delta Hc is the heat of combustion of the supplement . We conclude that while the among-laboratory variation in the D of difficult-to-ferment NSP is too large for the reliable prediction of energy value the method for the direction determination of DE is both reproducible and repeatable, that DE is independent of dosage of DF supplement up to 100 g/kg diet, and that it is safe to discriminate between energy values with a precision of 3 kJ/g . The conversion of both DE and D to net metabolizable energy for the purpose of food labelling, tables and databases is described.

Trends Biotechnol, 1995 Sep, 13(9), 388 - 92
Transgenic plants as vaccine production systems; Mason HS et al.; Transgenic plants that express foreign proteins with industrial or pharmaceutical value represent an economical alternative to fermentation-based production systems . Specific vaccines have been produced in plants as a result of the transient or stable expression of foreign genes . It has recently been shown that genes encoding antigens of bacterial and viral pathogens can be expressed in plants in a form in which they retain native immunogenic properties . Transgenic potato tubers expressing a bacterial antigen stimulated humoral and mucosal immune responses when they were provided as food . These results provide 'proof of concept' for the use of plants as a vehicle to produce vaccines.

Mol Cell Biol, 1995 Sep, 15(9), 4763 - 70
RPM2, independently of its mitochondrial RNase P function, suppresses an ISP42 mutant defective in mitochondrial import and is essential for normal growth; Kassenbrock CK et al.; RPM2 is identified here as a high-copy suppressor of isp42-3, a temperature-sensitive mutant allele of the mitochondrial protein import channel component, Isp42p . RPM2 already has an established role as a protein component of yeast mitochondrial RNase P, a ribonucleoprotein enzyme required for the 5' processing of mitochondrial precursor tRNAs . A relationship between mitochondrial tRNA processing and protein import is not readily apparent, and, indeed, the two functions can be separated . Truncation mutants lacking detectable RNase P activity still suppress the isp42-3 growth defect . Moreover, RPM2 is required for normal fermentative yeast growth, even though mitochondrial RNase P activity is not . The portion of RPM2 required for normal growth and suppression of isp42-3 is the same . We conclude that RPM2 is a multifunctional gene . We find Rpm2p to be a soluble protein of the mitochondrial matrix and discuss models to explain its suppression of isp42-3.

Gene, 1995 Aug 8, 161(1), 75 - 9
Carbon source-dependent regulation of the acetyl-coenzyme A synthetase-encoding gene ACS1 from Saccharomyces cerevisiae; Kratzer S et al.; The yeast ACS1 gene, encoding acetyl-coenzyme A synthetase (ACS), was cloned using colony hybridization and a facA probe from Aspergillus nidulans . The complete sequence of 1.5 kb of the ACS1 upstream region was determined . Northern hybridization revealed a strong depression of ACS1 transcripts in a strain grown on the nonfermentable carbon sources, acetate or ethanol . In contrast to a previous report, delta acs1 null mutants did not exhibit a growth defect on acetate medium . Indeed, enzyme assays showed the presence of an additional constitutively expressed ACS activity in delta acs1 mutants . The carbon source-dependent expression was further investigated by the use of an ACS1::lacZ fusion gene, showing complete repression on easily fermentable sugars such as glucose, maltose, sucrose or galactose . Binding sites for the yeast general regulatory factors, Abf1p and Reb1p, together with a sequence reminiscent of the recently identified carbon source-responsive element (CSRE), could be detected in the ACS1 upstream region, presumably mediating the observed regulatory phenotype of this ACS isoenzyme.

J Dairy Sci, 1995 Aug, 78(8), 1837 - 42
Effect of forage to concentrate ratio on disappearance of vitamins A and E during in vitro ruminal fermentation; Weiss WP et al.; The effects of forage to concentrate ratio and the commercial form of vitamins A and E on in vitro ruminal disappearance of retinol and alpha-tocopherol were studied . Ruminally fistulated cows were fed diets with either 80 or 50% forage . In vitro substrates that were similar to those fed to the donor cows were incubated with buffered ruminal fluid for 24 h . Different commercial forms of vitamin E (spray-dried, silicic acid adsorbate, and lipid-encased forms) and vitamin A (gelatin beadlet and lipid-encased forms) were added to the flasks . The vitamin E was all-rac-alpha-tocopheryl acetate, and the vitamin A was all-trans-retinyl acetate . The amount of alpha-tocopherol in the flasks was not affected by diet or form of vitamin E and did not change over the 24-h incubation . Retinol disappearance was not affected by form of vitamin A but was substantially higher for the 50% forage diet than for the 80% forage diet (72 vs . 20% at 24 h) . These data suggest that ruminal metabolism of vitamin E is minimal and not affected by forage to concentrate ratio . Additionally, vitamin A destruction in the rumen was much higher when cows were fed a typical lactation diet than when fed a typical dry cow diet.

J Dairy Sci, 1995 Aug, 78(8), 1815 - 23
Steady-state rates of linoleic acid biohydrogenation by ruminal bacteria in continuous culture; Fellner V et al.; Ruminal biohydrogenation of linoleic acid was determined in fermenters with a continuous culture of microorganisms . Rates of biohydrogenation and changes of fatty acids in culture were measured during steady-state concentration of linoleic acid that was achieved by continuous infusion of linoleic acid into the fermenters . A number of trans and cis isomers were identified using a GLC equipped with an infrared detector . The infusion of linoleic acid resulted in a substantial increase in the content of trans-C18:1 and a lesser increase in cis-C18:1 . the major trans peak consisted of a mixture of n-9 and n-7 isomers . Biohydrogenation of infused linoleic acid averaged 77% . There was evidence of fatty acid loss, as determined by a decrease in the recovery of linoleic acid after 8 h of infusion . Addition of C18:2n-6 had no major effect on the VFA production by ruminal microorganisms . The results were similar to those measured in vivo, indicating that artificial fermenters were reliable predictors of fatty acid metabolism in vivo.

J Dairy Sci, 1995 Aug, 78(8), 1755 - 65
Effects of inoculation and wilting on the preservation and utilization of wheat forage; Williams CC et al.; Wheat forage was harvested at an early head stage of maturity and ensiled in 12 900-kg experimental silos at three percentages of DM (20.8% for direct-cut forage and 27.9 or 39.3% for wilted forage) either with or without application of a lactic acid bacterial inoculant . The objective was to test the efficacy of the inoculant to alter silage fermentation, preservation, and nutritive value of wheat forage ensiled at different moisture percentages because of wilting . Wilting enhanced DM preservation and decreased fermentation end products . Inoculation made the fermentation more homolactic but did not enhance DM preservation . Silage rations (80% DM as silage) were fed at 1.8% of BW/d to six ruminally and abomasally fistulated steers (350 kg) in an experiment with a Latin-square design and a 3 x 2 factorial arrangement of treatments . Digestive responses to silage diets were not influenced by inoculation . Intake was depressed with direct-cut silage rations . Wilting improved fiber digestibility and was associated with changes in ruminal contents and fermentation end products . Wilting appears to be more effective than inoculation as a postharvest management tool to improve small grain silage.

Sci China B, 1995 Aug, 38(8), 954 - 62
Analysis of heterogeneity of gene products (interferon) expressed in yeast; Wang H et al.; FPLC, SDS-PAGE and Western blot techniques are used to analyse the heterogeneity of interferon alpha A (IFN-alpha A) expressed in yeast . The heterogeneity consists of (i) the presence of IFN polymer, (ii) partial processing of signal leader peptide and (iii) internal degradation . The reasons for heterogeneity of gene products in expression system of yeast are analysed . The methods of avoiding heterogeneity, such as depolymerization, adding inhibitors of protease to the culture supernatant, the oligonucleotide-directed deletion mutagenesis and improvements of fermentation, are discussed.

J Bioenerg Biomembr, 1995 Aug, 27(4), 379 - 85
Regulation of alternative oxidase activity in higher plants; Day DA et al.; Plant mitochondria contain two terminal oxidases: cytochrome oxidase and the cyanide-insensitive alternative oxidase . Electron partioning between the two pathways is regulated by the redox poise of the ubiquinone pool and the activation state of the alternative oxidase . The alternative oxidase appears to exist as a dimer which is active in the reduced, noncovalently linked form and inactive when in the oxidized, covalently linked form . Reduction of the oxidase in isolated tobacco mitochondria occurs upon oxidation of isocitrate or malate and may be mediated by matrix NAD(P)H . The activity of the reduced oxidase is governed by certain other organic acids, notably pyruvate, which appear to interact directly with the enzyme . Pyruvate alters the interaction between the alternative oxidase and ubiquinol so that the oxidase becomes active at much lower levels of ubiquinol and competes with the cytochrome pathway for electrons . These requirements for activation of the alternative oxidase constitute a sophisticated feed-forward control mechanism which determines the extent to which electrons are directed away from the energy-conserving cytochrome pathway to the non-energy conserving alternative oxidase . Such a mechanism fits well with the proposed role of the alternative oxidase as a protective enzyme which prevents over-reduction of the cytochrome chain and fermentation of accumulated pyruvate.

J Anim Sci, 1995 Aug, 73(8), 2483 - 92
Methane emissions from cattle; Johnson KA et al.; Increasing atmospheric concentrations of methane have led scientists to examine its sources of origin . Ruminant livestock can produce 250 to 500 L of methane per day . This level of production results in estimates of the contribution by cattle to global warming that may occur in the next 50 to 100 yr to be a little less than 2% . Many factors influence methane emissions from cattle and include the following: level of feed intake, type of carbohydrate in the diet, feed processing, addition of lipids or ionophores to the diet, and alterations in the ruminal microflora . Manipulation of these factors can reduce methane emissions from cattle . Many techniques exist to quantify methane emissions from individual or groups of animals . Enclosure techniques are precise but require trained animals and may limit animal movement . Isotopic and nonisotopic tracer techniques may also be used effectively . Prediction equations based on fermentation balance or feed characteristics have been used to estimate methane production . These equations are useful, but the assumptions and conditions that must be met for each equation limit their ability to accurately predict methane production . Methane production from groups of animals can be measured by mass balance, micrometeorological, or tracer methods . These techniques can measure methane emissions from animals in either indoor or outdoor enclosures . Use of these techniques and knowledge of the factors that impact methane production can result in the development of mitigation strategies to reduce methane losses by cattle . Implementation of these strategies should result in enhanced animal productivity and decreased contributions by cattle to the atmospheric methane budget.

J Anim Sci, 1995 Aug, 73(8), 2458 - 68
Effects of forage level and canola seed supplementation on site and extent of digestion of organic matter, carbohydrates, and energy by steers; Hussein HS et al.; The objective of this study was to determine the effects of fat supplementation from canola seed (CS) on ruminal fermentation and postruminal digestion of OM, carbohydrates, and energy of diets containing different levels of forage . Six ruminally and duodenally cannulated beef steers (354 kg +/- 18) were given ad libitum access to six isonitrogenous diets that were offered twice daily in a 6 x 6 Latin square design . Treatments were arranged as a 2 x 3 factorial with two forage levels (70 vs 30% of dietary DM as corn silage) and three forms of CS supplementation including no CS or CS added at 10% of dietary DM as whole CS treated with alkaline hydrogen peroxide or untreated crushed CS . Fat from CS provided 5% of dietary DM . The remaining dietary ingredients were corn, canola meal, molasses, and urea . No interactions (P > .05) between dietary forage level and CS supplementation were observed for ruminal characteristics or digestion of OM, carbohydrates, and energy in the rumen, postruminally, or in the total tract . Fat supplementation from CS did not affect (P > .05) DMI . With few exceptions, fat supplementation did not affect (P > .05) ruminal, postruminal, or total tract digestibilities of OM, structural and nonstructural carbohydrates, and GE . Ruminal disappearance of GE was decreased (P < .05) when diets were supplemented with fat from whole treated CS, and total tract digestibilities of OM and GE were decreased (P < .05) when diets were supplemented with fat from CS in either form . Ruminal pH, concentrations of NH3 N and total VFA, and molar proportions of acetate, propionate, and butyrate were not affected (P > .05) by fat supplementation . Results suggest that fat supplementation from CS (at 5% of dietary DM) as whole treated or untreated crushed had no negative effects on ruminal fermentation of OM, carbohydrates, or energy when steers were given ad libitum access to diets containing high or low forage.

J Anim Sci, 1995 Aug, 73(8), 2428 - 37
Influence of altering ruminal degradation of soybean meal protein on in situ ruminal fiber disappearance of forages and fibrous byproducts; Hussein HS et al.; The objective was to determine the effects of altering ruminal CP degradation of soybean meal (SBM) by roasting (Exp . 1) on ruminal characteristics and extents of in situ disappearance of DM, OM, and fiber components (Exp . 2) . A control diet (8.2% CP) containing oat hulls, corn silage, starch grits, ammoniated corn cobs, and molasses was supplemented to 17.1% CP with unroasted SBM (SBM-0) or SBM roasted at 165 degrees C for 75, 150, or 210 min (SBM-75, SBM-150, and SBM-210, respectively) . In Exp . 1, SBM was incubated for 0, 2, 4, 8, 12, 16, and 24 h in the rumen of two steers that were fed the SBM-0 diet . Extents of ruminal CP degradation and rates of N disappearance decreased (P < .05) linearly with increasing roasting time of SBM . In Exp . 2, five ruminally cannulated steers were used in a 5 x 5 Latin square design and were fed the five diets listed above during five 11-d periods . On d 11, five substrates (alfalfa hay, orchardgrass hay, corn silage, soy hulls, and wheat straw) were incubated in the rumen for 24 h . Extents of in situ disappearance of DM, OM, and fiber (NDF, ADF, cellulose, hemicellulose, and total dietary fiber) were analyzed as a split-plot design . No substrate x diet interaction (P > .05) was observed for any of the measurements evaluated . Extents of in situ disappearance (24 h) of DM, OM, and fiber were highest (P < .05) when the control diet was fed and were lowest (P < .05) when the SBM-0 diet was fed . Decreasing the availability of SBM protein in the diet by roasting increased (P < or = .10) extents of in situ disappearance of DM, OM, and fiber linearly . These extents were similar for steers fed the control diet or the diet containing SBM-210 . Ruminal concentrations of NH3 N, branched-chain VFA, and valerate were highest (P < .05) and ruminal pH lowest (P < .05) when the SBM-0 diet was fed . Results indicated a rapid ruminal fermentation of both protein and readily available carbohydrates of SBM (resulting in pH below 6.0) during the first 4.5 h after feeding the SBM-0 diet . Making both protein and readily available carbohydrates of SBM more slowly fermentable by roasting slowed early fermentation processes, maintained higher ruminal pH, and encouraged earlier and faster ruminal fiber digestion.

J Clin Pharm Ther, 1995 Aug, 20(4), 235 - 41
Dental properties of antiseptic throat lozenges formulated with sugars or Lycasin; Grenby TH; Thirteen different formulations of throat lozenges were examined for their acidity, demineralizing action on hydroxylapatite, and fermentability by human dental plaque micro-organisms . Their flavouring acids gave them low pH values in the range 2.6-3.7, leading to the dissolution of calcium and phosphorus from hydroxylapatite . The combination of antiseptics and flavouring acids in the lozenges inhibited microbial growth and metabolism . In the absence of any antiseptics and flavouring acids, the growth and metabolic activity of cultures of plaque micro-organisms were significantly greater on sucrose+glucose lozenges than on a new Lycasin formulation.

Clin Invest Med, 1995 Aug, 18(4), 296 - 302
Implications of altering the rate of carbohydrate absorption from the gastrointestinal tract; Jenkins DJ et al.; The rate of absorption of carbohydrate from the small intestine plays a major role in determining the metabolic effects of dietary carbohydrate . Factors which reduce the rate of absorption include the nature of the starch and sugars, and the presence of vegetable proteins, fats, viscous fibre, and antinutrients, including lectins and phytates . The rate of absorption can also be manipulated by the use of specific enzyme inhibitors and by increasing the number and frequency of meals while holding caloric intake constant . All these factors contribute to the creation of what may be termed slow release or "lente carbohydrate" . The slowing of small intestinal absorption, as exemplified by increased meal frequency ("nibbling"), results in reduced postprandial insulin secretion and lower low-density lipoprotein (LDL) cholesterol and apolipoprotein B concentrations . A further effect of some manipulations which reduce the rate of absorption is increased delivery of carbohydrate to the colon and its absorption after bacterial fermentation to short-chain fatty acids (SCFA) . These SCFA may have beneficial effects on colonic health(butyrate) or further inhibit cholesterol synthesis in the liver (propionate) . Thus the absorption of "lente carbohydrate" takes place along the full length of the gastrointestinal tract with a wide variety of physiological consequences.

Antonie Van Leeuwenhoek, 1995 Aug, 68(2), 165 - 71
Taxonomy of Penicillium nalgiovense isolates from mould-fermented sausages; Andersen SJ; A large number of Penicillium nalgiovense isolates from mould fermented sausages and the ex type culture were examined for characters of morphology, physiology and production of secondary metabolites . To separate biotypes within the P . nalgiovense species, the data obtained were evaluated using multivariate statistical methods . The macromorphological characters of the ex type culture and isolates from meat products appeared to be distinctive . The ex type culture is characterized by a brown reverse on both Czapek yeast extract and malt extract agar while the isolates from meat products have a yellow to orange reverse . Proteolytic and/or lipolytic activity was demonstrated by 75% of the examined cultures and all of them demonstrated ability to utilize lactate as sole carbon source . Growth on creatine sucrose agar was very inhibited and acid production was absent or very weak . TLC analysis showed production of three unknown secondary metabolites that constituted the characteristic profile . HPLC analysis showed production of only three known secondary metabolites; chrysogine (96%), nalgiolaxin and nalgiovensin (9%) . The ex type culture produced nalgiolaxin and nalgiovensin but not chrysogine . The chemometric evaluation showed that P . nalgiovense isolates from meat products from a homogenous species, which can not be divided into biotypes . The only indication of grouping, beside a separation of the ex type culture, was related to the conidium colour (white, turquoise or grey green) . The examined P . nalgiovense isolates showed some resemblance (morphologically and chemically) to P . chrysogenum.

Biochem Mol Biol Int, 1995 Aug, 36(6), 1263 - 8
Bio-Catalyzer alpha . rho No . 11 (Bio-Normalizer) supplementation: effect on oxidative stress to isolated rat hearts; Haramaki N et al.; Bio-Catalyzer alpha . rho No . 11 (Bio-Normalizer), a natural health food product prepared by yeast fermentation of medicinal plants, has been recently reported to possess antioxidant properties . To better define its antioxidant action, we investigated the effects of orally supplemented Bio-Normalizer on oxidative damage in the rat heart . Hearts were isolated from control or Bio-Normalizer supplemented animals and 1) exposed to ischemia-reperfusion using the Langendorff technique, or 2) homogenized and exposed to peroxyl radicals generated from (2,2'-azobis (2,4'-dimethylvaleronitrile) (AMVN) . During reperfusion following 40 minutes of ischemia, leakage of lactate dehydrogenase from hearts isolated from Bio-Normalizer supplemented rats was significantly lower than from hearts of control animals . Furthermore, lower levels of AMVN-induced accumulation of thiobarbituric acid reactive substances and of protein carbonyl derivatives were measured in homogenates prepared from hearts isolated from Bio-Normalizer supplemented rats than in samples from control animals . Our findings confirm an antioxidant action of Bio-Normalizer and show that it protects the heart against ischemia-reperfusion induced damage.

Protein Expr Purif, 1995 Aug, 6(4), 512 - 8
Large-scale production of HIV-1 protease from Escherichia coli using selective extraction and membrane fractionation; Gustafson ME et al.; Human immunodeficiency virus type 1 (HIV-1) protease was expressed in Escherichia coli as a fusion protein with the N-terminal sequence of IGF-2 . The protein accumulated in inclusion bodies as a 40:60 mixture of unprocessed fusion protein and processed protein . A simple purification procedure was developed that yielded 30-40 mg of active protease per liter of fermentation broth with a recovery of 30-40% . The purification process involved the selective extraction of HIV-1 protease from E . coli inclusion bodies with 50% acetic acid and fractional diafiltration to remove impurities and low-molecular-weight protease-related fragments . No chromatographic steps were employed, yet the HIV-1 protease produced by this procedure was greater than 95% pure by SDS-PAGE, reverse-phase HPLC, and N-terminal sequence analysis.

Analyst, 1995 Aug, 120(8), 2101 - 5
Automated determination of microbial peroxidase activity in fermentation samples using hydrogen peroxide as the substrate and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) as the electron donor in a flow injection system; Holm KA; An automated flow injection method has been developed for the determination of microbial peroxidase activity . The substrate used was hydrogen peroxide and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate (ABTS) was used as the electron donor . In the presence of hydrogen peroxide, peroxidase catalyses the dehydrogenation of ABTS, resulting in the formation of a resonance-stabilized radical cation of ABTS . The green-blue colour formed, recorded at 418 nm, is taken as a measure of the peroxidase activity . The general technical conditions and the general enzymic kinetics have been optimized . Conditions for activation and stabilization of the enzyme were found, e.g., ammonium sulfate acts as a peroxidase activator . The resulting method has a good precision, sensitivity and speed.

J Bacteriol, 1995 Aug, 177(16), 4757 - 64
Purification, characterization, and metabolic function of tungsten-containing aldehyde ferredoxin oxidoreductase from the hyperthermophilic and proteolytic archaeon Thermococcus strain ES-1; Heider J et al.; Thermococcus strain ES-1 is a strictly anaerobic, hyperthermophilic archaeon that grows at temperatures up to 91 degrees C by the fermentation of peptides . It is obligately dependent upon elemental sulfur (S(o)) for growth, which it reduces to H2S . Cell extracts contain high aldehyde oxidation activity with viologen dyes as electron acceptors . The enzyme responsible, which we term aldehyde ferredoxin oxidoreductase (AOR), has been purified to electrophoretic homogeneity . AOR is a homodimeric protein with a subunit M(r) of approximately 67,000 . It contains molybdopterin and one W, four to five Fe, one Mg, and two P atoms per subunit . Electron paramagnetic resonance analyses of the reduced enzyme indicated the presence of a single {4Fe-4S}+ cluster with an S = 3/2 ground state . While AOR oxidized a wide range of aliphatic and aromatic aldehydes, those with the highest apparent kcat/Km values (> 10 microM-1S-1) were acetaldehyde, isovalerylaldehyde, and phenylacetaldehyde (Km values of < 100 microM) . The apparent Km value for Thermococcus strain ES-1 ferredoxin was 10 microM (with crotonaldehyde as the substrate) . Thermococcus strain ES-1 AOR also catalyzed the reduction of acetate (apparent Km of 1.8 mM) below pH 6.0 (with reduced methyl viologen as the electron donor) but at much less than 1% of the rate of the oxidative reaction (with benzyl viologen as the electron acceptor at pH 6.0 to 10.0) . The properties of Thermococcus strain ES-1 AOR are very similar to those of AOR previously purified from the saccharolytic hyperthermophile Pyrococcus furiosus, in which AOR was proposed to oxidize glyceraldehyde as part of a novel glycolytic pathway (S . Mukund and M . W . W . Adams, J . Biol . Chem . 266:14208-14216, 1991) . However, Thermococcus strain ES-1 is not known to metabolize carbohydrates, and glyceraldehyde was a very poor substrate (kcat/Km of < 0.2 microM-1S-1) for its AOR . The most efficient substrates for Thermococcus strain ES-1 AOR were the aldehyde derivatives of transaminated amino acids . This suggests that the enzyme functions to oxidize aldehydes generated during amino acid catabolism, although the possibility that AOR generates aldehydes from organic acids produced by fermentation cannot be ruled out.

J Bacteriol, 1995 Aug, 177(16), 4748 - 56
Effects of elemental sulfur on the metabolism of the deep-sea hyperthermophilic archaeon Thermococcus strain ES-1: characterization of a sulfur-regulated, non-heme iron alcohol dehydrogenase; Ma K et al.; The strictly anaerobic archaeon Thermococcus strain ES-1 was recently isolated from near a deep-sea hydrothermal vent . It grows at temperatures up to 91 degrees C by the fermentation of peptides and reduces elemental sulfur (S(o)) to H2S . It is shown here that the growth rates and cell yields of strain ES-1 are dependent upon the concentration of S(o) in the medium, and no growth was observed in the absence of S(o) . The activities of various catabolic enzymes in cells grown under conditions of sufficient and limiting S(o) concentrations were investigated . These enzymes included alcohol dehydrogenase (ADH); formate benzyl viologen oxidoreductase; hydrogenase; glutamate dehydrogenase; alanine dehydrogenase; aldehyde ferredoxin (Fd) oxidoreductase; formaldehyde Fd oxidoreductase; and coenzyme A-dependent, Fd-linked oxidoreductases specific for pyruvate, indolepyruvate, 2-ketoglutarate, and 2-ketoisovalerate . Of these, changes were observed only with ADH, formate benzyl viologen oxidoreductase, and hydrogenase, the specific activities of which all dramatically increased in cells grown under S(o) limitation . This was accompanied by increased amounts of H2 and alcohol (ethanol and butanol) from cultures grown with limiting S(o) . Such cells were used to purify ADH to electrophoretic homogeneity . ADH is a homotetramer with a subunit M(r) of 46,000 and contains 1 g-atom of Fe per subunit, which, as determined by electron paramagnetic resonance analyses, is present as a mixture of ferrous and ferric forms . No other metals or acid-labile sulfide was detected by colorimetric and elemental analyses . ADH utilized NADP(H) as a cofactor and preferentially catalyzed aldehyde reduction . It is proposed that, under So limitation, ADH reduces to alcohols the aldehydes that are generated by fermentation, thereby serving to dispose of excess reductant.

J Lab Clin Med, 1995 Aug, 126(2), 128 - 36
Dissociation between tissue iron concentrations and transferrin saturation among inbred mouse strains; Leboeuf RC et al.; Excessive absorption of dietary iron results in pathologic hepatic iron accumulation in the genetic disorder hemochromatosis . Genetic factors have also been suggested to play a role in African iron overload that is induced by the intake of iron-rich fermented beer . We have used inbred strains of mice to investigate previously unrecognized genetic factors controlling iron metabolism . Among different strains of mice fed a basal iron diet, serum iron levels varied twofold . In contrast, serum transferrin levels were remarkably constant . This indicates that transferrin saturation with iron, but not the serum level of transferrin, is likely to be genetically determined in mice . Hepatic iron stores also varied twofold among the different mouse strains . Remarkably, hepatic iron stores failed to reflect transferrin saturation, suggesting that different genetic factors control transferrin saturation and hepatic iron stores . When mice were challenged with a high-iron diet, the concentration of carbonyl iron required to completely saturate transferrin with iron was 10 times greater for C57BL/6 and BALB/c mice than for DBA/2 and AKR mice . These results are reminiscent of the iron-loading locus proposed to interact with dietary iron in African iron overload . Our studies with inbred strains of mice have revealed a number of novel control points in iron metabolism that may be genetically determined . The mouse model may thus be useful for understanding the molecular basis of hemochromatosis and African iron overload.

Carcinogenesis, 1995 Aug, 16(8), 1711 - 6
The consequences of fruit and vegetable fibre fermentation on their binding capacity for MeIQx and the effects of soluble fibre sources on the binding affinity of wheat bran preparations; Ryden P et al.; Fruits and vegetables provide dietary fibre some of which is partly soluble in the upper gut; in the colon it is highly fermentable . Using alcohol-insoluble residues prepared from a range of fruits and vegetables the effects of fermentation on the changes in composition and binding capacity have been assessed for the hydrophobic mutagen 2-amino-3,8-dimethylimidazo{4,5-f}quinoxaline (MeIQx) . Fermentation was extensive and resulted in destruction of most of the pectic polysaccharides . Of the unfermented vegetable fibre only cabbage had a measurable hydrophobic binding capacity . The binding capacities of unfermented apple, carrot and sugar beet were negligible . After fermentation, binding capacities, (per mg of fermented residue), increased . Although fermented cabbage was found to have the highest capacity of the fruit and vegetable fibres this remained less than the least effective of unfermented wheat bran samples which had a relatively high affinity for MeIQx . Mucin inhibited the binding of MeIQx to wheat bran fibre but apple fibre did not . The results show that the contribution of fruit and vegetable fibre to a hydrophobic binding matrix in the colon is insignificant and the suggested harmful effect of fruit and vegetable fibre, maintaining hydrophobic mutagens in solution, can be prevented by the presence of wheat bran fibre.

Am J Clin Nutr, 1995 Aug, 62(2), 403 - 11
Ileal recovery of starch from whole diets containing resistant starch measured in vitro and fermentation of ileal effluent; Silvester KR et al.; Six subjects with ileostomies consumed five diets containing 61-164 g starch/d of which 0.4-34.8 g was resistant starch (RS) . Ileal excretion of starch was 97% of that measured as dietary RS in vitro with no significant difference between RS fed and starch recovered on any of the test diets . Variation in starch excretion between subjects was partly due to differences in mouth-to-stoma transit time . In vitro fermentation of ileal effluent from RS-supplemented diets produced significantly more short-chain fatty acids, a higher molar proportion of butyrate (17% compared with 12%), and a lower concentration of ammonia compared with control subjects . These results indicate that the amount of starch that reaches the large intestine can be predicted from measurements in vitro for a wide range of RS intakes under normal eating conditions . They also support the hypothesis that RS, through fermentation, has distinctive influences on the colonic environment.

J Antibiot (Tokyo), 1995 Aug, 48(8), 768 - 72
The clecarmycins, new antitumor antibiotics produced by Streptomyces: fermentation, isolation and biological properties; Fujii N et al.; In the course of screening for microbial products with antitumor activity, new antitumor agents, clecarmycins, were isolated from culture broth of Streptomyces sp . DO-114 . The antibiotics were produced in a fermentation medium supplemented with a highly porous polymer resin which adsorbs antibiotics and results in a increase of titer . Active materials were separated from the polymer resin by solvent extraction procedure and two components named clecarmycin A1 and C were isolated by silica gel column chromatography . These were active against bacteria, and showed antiproliferative activities against human HeLa S3 cells . Clecarmycins exhibited antitumor activity against leukemia P388 and sarcoma 180 in mice.

Int J Food Sci Nutr, 1995 Aug, 46(3), 241 - 6
The effects of processing on the availability of lysine in kenkey, a Ghanaian fermented maize food; Nche PF et al.; The effects of processing steps such as soaking, fermentation, cooking and drying on the availability of lysine in kenkey were investigated . Soaking increased lysine availability by 21% and 22% for maize and maize-cowpea mixtures, respectively . Cooking of soaked samples further improved lysine availability by 68% and 31% for maize and maize-cowpea mixtures, respectively . Further significant improvements in lysine availability were effected by fermentation and cooking and values of 3.42 and 4.43 g/16 g N were recorded, respectively for maize and maize-cowpea doughs fermented for 4 days and cooked for 3 h . Cabinet drying had no significant effect on lysine availability, but drum drying of fermented maize and maize-cowpea doughs significantly lowered lysine availability in the resulting kenkey . A 1:1 mixture of cabinet and drum dried flours gave a product with higher available lysine content than the drum dried flour.

Int J Food Sci Nutr, 1995 Aug, 46(3), 189 - 93
Effect of amylase treatment on the consistency of cooked, fermented oat bran porridge; Raheem D; Oat bran porridges were cooked and fermented at 5, 10, 15, and 20% solids (as is basis) . Cooking was carried out on gas stove and viscograph . Supplementation with malt flour at 0.1, 0.25, 0.5, 0.75, and 1% . Cooked oat bran porridge was inoculated with fresh yoghurt and fermented 18 h overnight in an incubator at 42 degrees C . Falling number values were made to estimate the effects of amylase treatments by addition of malt flour on oat bran slurry when heated in an aqueous suspension . Pasting properties were observed with the viscograph and consistency measurements were made with Bostwick consistometer . The falling number method was not suitable for consistency measurements due to wide variations in values obtained . Enzymatic additions reduced the consistency of porridge with an increase in flowability during measurements . The peak heights obtained from the viscograms reduced proportionally with an increase in malt flour supplementation . The desirability of a product with higher energy values and a sufficiently low consistency that is spoonable was possible with cooked, fermented oat bran porridge.

J Ind Microbiol, 1995 Aug, 15(2), 94 - 102
Industrial yeast strain improvement: construction of a highly flocculent yeast with a killer character by protoplast fusion; Javadekar VS et al.; Conditions were optimized for rapid release and improved regeneration of protoplasts of Saccharomyces cerevisiae NCIM 3458 . Rapid protoplast release was also obtained with representatives of several other yeast genera under the modified conditions of treatment . The application of the procedure in construction of a highly flocculent Saccharomyces cerevisiae with a killer character is described . Fusion was effected between UV-killed protoplasts of S . cerevisiae NCIM 3578 with a killer character and live protoplasts of the highly flocculent S . cerevisiae NCIM 3528 in the presence of polyethylene glycol (PEG) 6000 . Fusants were selected using benomyl resistance as marker, the killer toxin producer rather than the highly flocculent yeast being resistant to the fungicide at a concentration of 100 micrograms ml-1 . Fusants were also characterized by their DNA contents, capacity for ethanolic fermentation of molasses sugar and levels of invertase, alcohol dehydrogenase and pyruvate decarboxylase activities.

J Ind Microbiol, 1995 Aug, 15(2), 80 - 4
Rapid identification of elaiophylin and geldanamycin in Streptomyces fermentation broths using CPC coupled with a photodiode array detector and LC-MS methodologies; Alvi KA et al.; During the course of screening microbial broth extracts in various high through-put bioassays (eg receptor binding or enzyme inhibition), several actinomycete cultures were discovered to produce active metabolites . The natural products elaiophylin and/or geldanamycin are produced by several Streptomyces violaceusniger strains, and the bioactivity of the extracts from these cultures was frequently associated with the fractions containing these metabolites . CPC coupled to a photodiode array detector and LC-MS techniques were applied to these broth extracts to ascertain rapidly when these natural products were present . These methodologies allowed us to identify the metabolites quickly in the crude extract, and the application demonstrated further the utility of CPC-photodiode array detection and LC-MS as powerful, initial analytical tools in analyses of the complex metabolite profiles produced by microorganisms.

J Ind Microbiol, 1995 Aug, 15(2), 75 - 9
Effect of pH, aeration and sucrose feeding on the invertase activity of intact S . cerevisiae cells grown in sugarcane blackstrap molasses; Vitolo M et al.; S . cerevisiae was grown in a blackstrap molasses containing medium in batch and fed-batch cultures . The following parameters were varied: pH (from 4.0 to 6.5), dissolved oxygen (DO) (from 0 to 5.0 mg O2 L-1) and sucrose feeding rate . When glucose concentration (S) was higher than 0.5 g L-1 a reduction in the specific invertase activity of intact cells (v) and an oscillatory behavior of v values during fermentation were observed . Both the invertase reduction and the oscillatory behavior of v values could be related to the glucose inhibitory effect on invertase biosynthesis . The best culture conditions for attaining S . cerevisiae cells suitable for invertase production were: temperature = 30 degrees C; pH = 5.0; DO = 3.3 mg O2 L-1; (S) = 0.5 g L-1 and sucrose added into the fermenter according to the equations: (V-Vo) = t2/16 or (V - Vo) = (Vf - Vo).(e0.6t-1)/10.

Gut, 1995 Aug, 37(2), 256 - 9
Breath hydrogen analysis in patients with ileoanal pouch anastomosis; Bruun E et al.; The possible influence on functional outcomes of hydrogen production in the ileoanal pouch after restorative proctocolectomy was investigated by means of lactulose H2 breath tests . Eight of 15 patients had significant increases in breath hydrogen after 10 g lactulose . One patient declined to participate in further investigations, the remaining seven responders had no evidence of small bowel bacterial overgrowth after glucose H2 breath tests . The ability to produce hydrogen by anaerobic fermentation of lactulose in the pouch was unrelated to the age of the patients or of the pouch . Seven of eight responders had successive breath tests after ingestion of lactulose 20 g and wheat starch 100 g . Five of seven had significant increases after lactulose but none after wheat starch . The overall function of the pouch continence, spontaneity of defecation, and 24 hour stool frequency was significantly better in responders than in non-responders . The absence of H2 production of 100 g wheat starch may indicate either increased absorption or defective fermentation.

Br J Nutr, 1995 Aug, 74(2), 251 - 60
Exogenous and endogenous nitrogen flow rates and level of protein hydrolysis in the human jejunum after {15N}milk and {15N}yoghurt ingestion; Gaudichon C et al.; Milk and yoghurt proteins were 15N-labelled in order to measure the flow rate of exogenous N during digestion in the human intestine . After fasting overnight, sixteen healthy volunteers, each with a naso-jejunal tube, ingested either {15N}milk (n 7) or {15N}yoghurt (n 9) . Jejunal samples were collected every 20 min for 4 h . A significant stimulation of endogenous N secretion was observed during the 20-60 min period after yoghurt ingestion and the 20-40 min period after milk ingestion . The endogenous N flows over a 4 h period did not differ between the groups (44.3(SEM 6.5) mmol for milk and 63.5(SEM 5.9) mmol for yoghurt) . The flow rates of exogenous N indicated a delayed gastric emptying of the yoghurt N compared with N from milk . The jejunal non-protein N (NPN) flow rate increased significantly after milk and yoghurt ingestion due to an increase in the exogenous NPN flow rate . The NPN fraction of exogenous N ranged between 40 and 80% . The net gastro-jejunal absorption of exogenous N did not differ significantly between milk (56.7(SEM 8.5)%) and yoghurt (50.9(SEM 7)%) . The high level of exogenous N hydrolysis is in accordance with the good digestibility of milk products . Fermentation modifies only the gastric emptying rate of N and does not affect the level of diet hydrolysis, the endogenous N stimulation or the digestibility rate.

Br J Nutr, 1995 Aug, 74(2), 209 - 19
Effect of propionate on fatty acid and cholesterol synthesis and on acetate metabolism in isolated rat hepatocytes; Demigne C et al.; In the present study the actual role of propionic acid in the control of fatty acid and cholesterol synthesis was investigated in isolated liver cells from fed rats maintained in the presence of near-physiological concentrations of glucose, glutamine and acetate . Using 3H2O for lipid labelling, propionate appears as an effective inhibitor of fatty acid synthesis and to a lesser extent of cholesterol synthesis, even at the lowest concentration used (0.6 mmol/l) . Butyrate is a potent activator of both synthetic pathways, and the activating effect was not counteracted by propionate . Using 1-{14C}acetate, it was observed that propionate at a moderate concentration, or 1 mmol oleate/l, are both very effective inhibitors of 14C incorporation into fatty acid and cholesterol . This incorporation was drastically inhibited when propionate and oleate were present together in the incubation medium . The net utilization of acetate by rat hepatocytes was impaired by propionate, in contrast to oleate . 1-{14C}butyrate was utilized at a high rate for fatty acid synthesis, but to a lesser extent for cholesterol synthesis; both processes were unaffected by propionate . Intracellular citrate concentration was not markedly depressed by propionate, whereas it was strongly elevated by butyrate . In conclusion, propionate may represent an effective inhibitor of lipid synthesis when acetate is a major source of acetyl-CoA, a situation which is encountered with diets rich in readily-fermentable fibres . The present findings also suggest that propionate may be effective at concentrations close to values measured in vivo in the portal vein.

Arch Oral Biol, 1995 Aug, 40(8), 743 - 52
A comparative study of glucose and galactose uptake in pure cultures of human oral bacteria, salivary sediment and dental plaque; Ryan CS et al.; The ability to utilize glucose and the weaker sugar acidogen, galactose, was surveyed in salivary sediment, pooled dental plaque, and in pure cultures of the bacteria that numerically comprise most of the bacteria in these mixed microbial systems . Except for a veillonella isolate, which showed no uptake of either sugar, glucose was utilized more rapidly than galactose by the 27 pure cultures tested and by both sediment and plaque . This sugar difference was also seen for two other measures of glycolysis, formation of acid and previously studied ability to produce an acidic pH . Rates of uptake of the two sugars by individual pure cultures varied considerably . Generally, the Gram-positive bacteria utilized glucose and galactose at rates similar to those seen with salivary sediment and dental plaque, whereas the Gram-negative cultures tested showed much slower uptakes . Bacteria previously identified as arginolytic had lower glucose and galactose uptake rates than similar non-arginolytic micro-organisms . This, together with the ability to produce base from arginine, would explain their tendency to produce a less acidic pH . In pure culture mixtures, uptakes were generally predictable and indicated an averaging effect . When the microbial compositions of salivary sediment or dental plaque were altered by mixing with pure cultures of high glucolytic activity, such as many of the Gram-positives, glucose uptake was enhanced . The opposite was observed when the less glucolytic Gram-negative bacteria were similarly incorporated . As well as determining the glucose and galactose uptake rates of the various bacteria that collectively comprise the bulk of the salivary sediment and supragingival plaque microfloras, this study has shown how variation in microbial composition affects sugar uptake rates and has indicated how microbial composition could be manipulated to produce dental plaques with different capacities to ferment sugars and presumably different cariogenicities.

Prostaglandins Leukot Essent Fatty Acids, 1995 Aug, 53(2), 87 - 93
Prostaglandin synthesis in human cancer cells: influence of fatty acids and butyrate; Awad AB et al.; Previous research has suggested that prostaglandins (PGs) may play a role in the development of colon cancer since tumor cells produce more PGs than normal cells . However, the exact mechanism by which PGs play a role in the development of cancer is not known . In addition, factors that influence PG synthesis are not known since they are complicated by the presence of homeostatic mechanisms . To avoid the homeostatic mechanisms, the present research was designed to examine factors that may influence PG synthesis in an in vitro system, i.e., a tissue culture . We have chosen two human colon cancer cell lines that differ in their ability to metabolize long-chain fatty acids (LCFAs), LS174T cells and HT-29 cells . We examined the effect of LCFAs on their membrane fatty acid composition, growth, and ability to release the main PGs (PGE2 and PGI) . The LCFAs used were those most common in the colonic lumen {18:0, 18:2 (n-6), and 18:3 (n-3)} . In addition, we examined the effect of butyrate on the above mentioned parameters . Butyrate is produced in the colon through fermentation of dietary fibers . The data obtained suggest that although both of these tumor cell lines are of human colonic origin, they differ in their response to LCFAs and butyrate in some of the characteristics studied, such as growth, composition of membranes, and the relationship between membrane FA composition and PG synthesis . Polyunsaturated fatty acid supplementation stimulated the growth of HT-29 cells but not of LS174T cells when compared with growth in media supplemented with 18:0.(ABSTRACT TRUNCATED AT 250 WORDS)

J Pediatr Surg, 1995 Aug, 30(8), 1138 - 42
An intraluminal model of necrotizing enterocolitis in the developing neonatal piglet; Di Lorenzo M et al.; The most common risk factors for the development of necrotizing enterocolitis (NEC) are prematurity and enteral feeding . Most models of NEC involve ischemic insult resulting in generalized necrosis, different from the classical ileocecal predilection of NEC . This anatomic predisposition is explained by dysmotility of immature gut, leading to bacterial overgrowth in the terminal ileum and colon . Infant formula containing lactose as the sole carbohydrate source overwhelms partially developed lactase activity, allowing enteric bacteria to ferment excess carbohydrate to short-chain fatty acids, decreasing intraluminal gut pH and predisposing to mucosal injury . Impaired clearance of intraluminal contents exacerbates this effect . In the present study the authors used a model of NEC, originally developed in rabbits and based on analysis of intestinal contents of NEC babies, modified and adapted here to neonatal piglets, the gastrointestinal tract of which more closely resembles the human neonate . METHOD: Piglets < 3 days old and 2 weeks old were laparotomized . Loops created from the distal ileum to the proximal colon were injected with isoosmolar acidified casein solution or 0.9% saline . Segments were harvested 3 hours later, sectioned for H&E, and graded from 0 (intact villi) to 4 (transmural necrosis) . RESULTS: Acidified casein-induced damage included areas of necrosis, submucosal edema, inflammatory cell infiltrate, and lymphatic distension . In younger animals, lesions were more pronounced (3.25 +/- 0.13 for the < 3-day-old v 2.43 +/- 0.14 for the 2-week-old piglets; P < .005) . CONCLUSION: The authors believe that this piglet NEC model most closely approximates human NEC because it incorporates two of the most common risk factors: dysmotility (by creating intestinal loops) and enteral feeding (by intraluminal injection of acidified casein).

EMBO J, 1995 Jul 17, 14(14), 3480 - 6
The membrane of peroxisomes in Saccharomyces cerevisiae is impermeable to NAD(H) and acetyl-CoA under in vivo conditions; van Roermund CW et al.; We investigated how NADH generated during peroxisomal beta-oxidation is reoxidized to NAD+ and how the end product of beta-oxidation, acetyl-CoA, is transported from peroxisomes to mitochondria in Saccharomyces cerevisiae . Disruption of the peroxisomal malate dehydrogenase 3 gene (MDH3) resulted in impaired beta-oxidation capacity as measured in intact cells, whereas beta-oxidation was perfectly normal in cell lysates . In addition, mdh3-disrupted cells were unable to grow on oleate whereas growth on other non-fermentable carbon sources was normal, suggesting that MDH3 is involved in the reoxidation of NADH generated during fatty acid beta-oxidation rather than functioning as part of the glyoxylate cycle . To study the transport of acetyl units from peroxisomes, we disrupted the peroxisomal citrate synthase gene (CIT2) . The lack of phenotype of the cit2 mutant indicated the presence of an alternative pathway for transport of acetyl units, formed by the carnitine acetyltransferase protein (YCAT) . Disruption of both the CIT2 and YCAT gene blocked the beta-oxidation in intact cells, but not in lysates . Our data strongly suggest that the peroxisomal membrane is impermeable to NAD(H) and acetyl-CoA in vivo, and predict the existence of metabolite carriers in the peroxisomal membrane to shuttle metabolites from peroxisomes to cytoplasm and vice versa.

J Biol Chem, 1995 Jul 7, 270(27), 16023 - 9
Site-specific isotope fractionation in the characterization of biochemical mechanisms . The glycolytic pathway; Zhang BL et al.; For a given biochemical transformation, such as the fermentation reaction, the redistribution coefficients, which relate the natural site-specific isotope contents in end products to those of their precursors, are a source of mechanistic information . These coefficients characterize the traceability of specific hydrogens in the products (ethanol and water) to their parent hydrogens in the starting materials (glucose and water) . In conditions of complete transformation, they also enable intermolecular exchanges with the water medium to be estimated . Thus it is directly confirmed that hydrogens 1, 2, 6, and 6' of glucose are strongly connected to the methyl site I of ethanol obtained by fermentation by Saccharomyces cerevisiae . However, whereas hydrogens 6 and 6' are transferred to a great extent, transfer is only partial for hydrogen 2, and it is even less for hydrogen 1 . Because the two moieties of glucose corresponding to carbons 1-2-3 and 4-5-6 are scrambled by the aldolase and triosephosphate isomerase reactions, additional exchange of hydrogens at positions 1 and 2 must have occurred before these steps . The value of the coefficient that relates site 2 of glucose to site I of ethanol in particular can be used to quantify the contribution of intermolecular exchange occurring in the course of the transfer from site 2 of glucose 6-phosphate to site 1 of fructose 6-phosphate mediated by phosphoglucoisomerase . The average hydrogen isotope effects associated with the transfer of hydrogen from the water pool to the methyl or methylene site of ethanol are estimated . In contrast to conventional experiments carried out in strongly deuterium-enriched media where metabolic switching may occur, the NMR investigation of site-specific natural isotope fractionation, which operates at tracer isotopic abundance, faithfully describes the unperturbed metabolic pathways.

Gene, 1995 Jul 4, 160(1), 135 - 6
A Saccharomyces cerevisiae gene essential for viability has been conserved in evolution; Rinaldi T et al.; To identify the gene coding for the endonuclease which processes the 3' end of mitochondrial (mt) tRNA transcripts in Saccharomyces cerevisiae, nuclear mutations able to complement a mt mutant (Ts932) defective for this process were isolated and analyzed . One of these mutants exhibited a growth defect both on respiratory and fermentable media . Complementation of this phenotype with a S . cerevisiae centrometric wild-type genomic library has allowed us to identify a new essential S . cerevisiae gene strongly conserved in various eukaryotic organisms.

Plant Foods Hum Nutr, 1995 Jul, 48(1), 31 - 8
The effect of solvent treatment on the chemical composition and organoleptic acceptability of traditional condiments from Nigeria; Arogba SS et al.; Three Nigerian condiments from locust bean, melon, and soya bean were prepared by the traditional technique of uncontrolled fermentation and then partly defatted by hexane and di-ethyl ether extraction respectively . Proximate analysis and consumer preference tests were conducted . Results showed that while crude protein, ash and fibre contents remained virtually unchanged, the carbohydrate contents of the treated condiments (derived by difference) increased remarkably . The increase was associated with the significant reduction of about 50% (p = 0.05) in lipid contents of the three condiments . The observed solvent effect correlated positively with panelists' preference rating for the treated locust bean and melon condiments . Except with the soya bean condiment, higher mean scores were observed after the solvent treatment for the four sensory attributes assessed . However, condiment-type and treatment notwithstanding, colour and odour appear to critically determine the level of acceptability of condiments.

Antibiot Khimioter, 1995 Jul, 40(7), 3 - 7
{Effect of nitrogen-containing compounds on the biosynthesis of avermectins}; Sergeev AV et al.; The influence of complex nitrogen-containing substrates (Difko yeast extract, EKD nutrient yeast extract, soy bean flour and cotton seed meal), ammonium salts and some amino acids (alanine, methionine, valine, isoleucine and threonine) on the biosynthesis of avermectins in the cultures of two mutants of Streptomyces avermitilis was studied . It was shown that an excess of the nitrogen compounds in the fermentation medium induced a decrease in the antibiotic biosynthesis and the relative content of the group B avermectins.

Int J Syst Bacteriol, 1995 Jul, 45(3), 560 - 4
Taxonomy of the feline mycoplasmas Mycoplasma felifaucium, Mycoplasma feliminutum, Mycoplasma felis, Mycoplasma gateae, Mycoplasma leocaptivus, Mycoplasma leopharyngis, and Mycoplasma simbae by 16S rRNA gene sequence comparisons; Brown DR et al.; The nucleotide sequence of the 16S rRNA gene of eight mycoplasmas isolated from felids was determined and used for taxonomic comparisons . A signature nucleotide sequence motif and overall sequence similarity to other mollicutes positioned Mycoplasma felifaucium, Mycoplasma felis, Mycoplasma leocaptivus, Mycoplasma leopharyngis, and Mycoplasma simbae in the Mycoplasma fermentans phylogenetic group of mollicutes . Mycoplasma arginini and Mycoplasma gateae were positioned in the Mycoplasma hominis phylogenetic group of mollicutes, and Mycoplasma feliminutum was positioned in the phylogenetically distant Acholeplasma group of mollicutes, showing that host family preference does not necessarily derive from bacterial phylogenetic closeness.

Curr Genet, 1995 Jul, 28(2), 184 - 9
Detection of a protein which binds specifically to the upstream region of the pcbAB gene in Penicillium chrysogenum; Chu YW et al.; The upstream region of the pcbAB gene from Penicillium chrysogenum was screened for protein-binding sites using an electromobility shift assay . A specific protein/DNA interaction was detected within a fragment covering the region -387 to -242 relative to the pcbAB translational start codon . The appearance of this protein and pcbAB mRNA in culture extracts occurred at the same time point in fermentations, suggesting that the protein might be a transcription activator . The putative upstream activating sequence was located more precisely using cross-competition assays . These indicated the involvement of the 7-bp motif TGCCAAG in the binding of the protein.

Mol Biochem Parasitol, 1995 Jul, 73(1-2), 91 - 101
Phosphoenolpyruvate carboxykinase from Trypanosoma cruzi . Purification and physicochemical and kinetic properties; Cymeryng C et al.; Phospho enolpyruvate carboxykinase (PEPCK) has been purified to homogeneity from epimastigotes of the Tul 0 strain of Trypanosoma cruzi . The physicochemical parameters determined allowed the calculation of an average molecular mass of 120 kDa; the subunit molecular mass, about 61 kDa, is in good agreement with the value of 58.6 kDa recently determined from the sequence by Sommer et al . (FEBS Lett . 359 (1994) 125-129) . The PEPCK from T . cruzi presented, in addition to its molecular mass, typical properties of other ATP-linked PEPCKs, namely strict specificity for ADP in the carboxylation reaction and lower specificity in the decarboxylation and exchange reactions, and synergistic activation by CdCl2 or MgCl2 when added in addition to MnCl2 . The enzyme presented hysteretic behaviour, shown by a lag period in the carboxylation reaction, which was affected by dilution and preincubation . The decarboxylation reaction catalyzed by the T . cruzi PEPCK was not inhibited by excess of ATP-Mn . The apparent Km values for the carboxylation reaction, including the low value for PEP (0.035 mM) are compatible with an important role of PEPCK, as suggested by previous NMR experiments, on the CO2 fixation in vivo which leads to succinate excretion during aerobic fermentation of glucose.

J Pediatr Gastroenterol Nutr, 1995 Jul, 21(1), 73 - 81
Improved energy intakes using amylase-digested weaning foods in Tanzanian children with acute diarrhea; Darling JC et al.; Amylase from germinating cereal grains enables the preparation of porridge with a higher energy density than conventional weaning foods . This food can be combined with fermentation, which inhibits pathogen growth . These food technologies are inexpensive, can be implemented at the household level, and are therefore particularly appropriate for use in developing countries . In a controlled clinical trial, 75 children aged 6-25 months admitted to hospital with acute diarrhea were rehydrated and then randomly allocated to three corn porridge dietary groups: conventional, amylase-digested (AMD), and fermented and amylase-digested (FAD) . The study diets were given ad libitum five times daily, and all intakes except breast milk were weighed . Mean daily energy intakes over 4 days in the conventional AMD, and FAD groups, respectively, were 32.4 (95% CI 28.7-36.6), 46.0 (CI 39.6-53.4), and 37.3 (CI 31.8-43.9) kcal/kg/day . The energy intake in the AMD group was 42% higher than the conventional group (p = 0.003) . There were no significant differences between the groups for duration of diarrhea, frequency of stooling, or vomiting . Starch digestion using amylase from germination is an effective way of improving energy intake in children with acute diarrhea.

Ukr Biokhim Zh, 1995 Jul-Aug, 67(4), 107 - 10
Stoichiometry of pectin and glucose fermentation in Prevotella ruminicola; Marounek M et al.; Prevotella ruminicola is an important rumen pectinolytic bacterium . Strain 659 was grown anaerobically at pH 6.5 and temperature 39 degrees C in LF2 fermenters on media containing glucose or pectin (4 g/l) in order to determine its fermentation stoichiometry and growth parameters . Both substrates were utilized almost completely (> 90%) . The growth on pectin was more rapid than on glucose . Pectin and glucose differed considerably in composition of fermentation end-products . Production of acetate was significantly higher when P . ruminicola 659 was grown on pectin, while production of other metabolites (formate, succinate, lactate) was lower than on glucose . Production of dry cell matter was significantly higher in cultures supplied with glucose . An increase in dry matter and protein yields calculated per carbon was not verified.

Mikrobiol Z, 1995 Jul-Aug, 57(4), 89 - 105
Molecular biological bases of resistance to HIV/AIDS (the hypothesis with elements of the theory); Skripal IG; Proceeding from the structure and function of the shell glycoprotein gp120 of the human immunodeficiency virus (HIV) and receptor glycoprotein CD4 on target cells for this virus, the author assumes that in nature there is genetically determined human resistance to the HIV infection and AIDS . This resistance manifests itself indirectly via products of the glycosylation system and via the composition and order of amino-acid residues in receptor CD4 sites responsible for interaction between the receptor and glycoprotein gp120 . The author thinks that people in whom the glycosylation system determines either B(III) or AB(IV) blood groups are potential subjects of the HIV infection . But development of AIDS necessitates some conditions more, one of them is susceptibility of the human organism to be infected with mollicute Mycoplasma fermentans . This mycoplasma is able to recognize terminal NeuAc alpha 2-3 Gal in the composition of oligosaccharides of gp120, which permits it to adhere HIV virions on itself and then to transport them directly to the cells expressing receptor CD4 and having oligosaccharides of the same terminal structure . Oligosaccharides of glycocalyx of the mycoplasma protect it from the action of the human immune system and the mycoplasma, having "transported" HIV virions to target cells combines with membranes of the latter, stimulates formation by them of interleukin-1 and tumour necrosis factor, the known effectors of this virus reproduction . On the basis of all these factors the author identifies four types of human resistance to HIV/AIDS.

J Ind Microbiol, 1995 Jul, 15(1), 60 - 5
Korkormicins, novel depsipeptide antitumor antibiotics from Micromonospora sp C39500: fermentation, precursor directed biosynthesis and biological activities; Lam KS et al.; Micromonospora sp C39500, isolated in our laboratory from a soil sample, produced a complex of seven novel depsipeptide antitumor antibiotics, designated korkormicins . The major component of the complex, korkormicin A, has a MW of 1452 and a molecular formula of C66H84N16O22 . Korkormicin A exhibits potent in vivo antitumor activity against P388 leukemia and M109 lung carcinoma implanted intraperitoneally (ip) in mice, with effective doses of 0.05-0.20 mg kg-1 injection-1, for five or three ip injections, respectively . It is also active against Gram-positive bacteria but inactive against Gram-negative bacteria . The production of korkormicin A was enhanced by 3-fold when 0.1% L-valine was added to the production culture at 48 h . A titer of 401.0 micrograms ml-1 was achieved in the fermenter culture supplemented with 0.1% L-valine.

J Ind Microbiol, 1995 Jul, 15(1), 5 - 9
Production of brefeldin-A; McCloud TG et al.; Fermentation conditions are described for the production of the antitumor antibiotic 7-(S)-brefeldin-A (brefeldin-A) in liquid culture by Eupenicillium brefeldianum, (B.Dodge) Stolk and Scott, ATCC 58665 . An analytical hplc method was developed which allowed rapid quantitation of the compound during fermentation . A kilogram of brefeldin-A was isolated from a fermentation at the 6800-liter scale.

Biotechnol Prog, 1995 Jul-Aug, 11(4), 386 - 92
Effects of varying media, temperature, and growth rates on the intracellular concentrations of yeast amino acids; Martinez-Force E et al.; Variations of the yeast free amino acid pool under different culture conditions were studied in two Saccharomyces strains, the laboratory haploid strain S288C and the industrial fermentative yeast IFI256 . The internal amino acid pool of both strains was measured when grown in laboratory (minimal and complete) versus semiindustrial (molasses with or without added biotin and/or diammonium phosphate) media, in fermentable (glucose, fructose, sucrose) versus respirable (glycerol) carbon sources, in different temperatures (22, 30, and 37 degrees C), pHs (2.0-4.75), and growth rates (0.018-0.24 h-1) in continuous culture, and at different phases of the growth curve in batch culture (lag, exponential, early and late stationary) . Results indicated that environmental conditions, particularly the presence of amino acids in the media, enormously influenced the intracellular amino acid concentration . Higher values were detected in molasses than in laboratory media and in fermentable carbon sources (glucose, fructose, sucrose) than in glycerol . Variations in the amino acid pool along the growth curve were greater at 37 degrees C than at other temperatures; in all cases, the highest values were measured at the beginning of the exponential phase . In continuous culture and at different growth rates, intracellular free amino acid concentrations increased by 3-10-fold when the growth rate was lower than 0.05 h-1, representing 20-35% of the total (free plus protein) amino acid content and indicating that amino acid yield was a partly growth-linked parameter.

J Antibiot (Tokyo), 1995 Jul, 48(7), 714 - 9
New antibiotics phthoxazolins B, C and D produced by Streptomyces sp . KO-7888; Shiomi K et al.; New antibiotics, phthoxazolins B, C and D were isolated from the fermentation broth of Streptomyces sp . KO-7888 . They are geometrical isomers of 10-hydroxyphthoxazolin A . They showed selective antifungal activity against Phytophthora parasitica in vitro and modest herbicidal activity in a laboratory test, but the potencies were different among isomers.

J Antibiot (Tokyo), 1995 Jul, 48(7), 703 - 7
Isochromophilones I and II, novel inhibitors against gp120-CD4 binding produced by Penicillium multicolor FO-2338 . I . Screening, taxonomy, fermentation, isolation and biological activity; Matsuzaki K et al.; Isochromophilones I and II, the first novel gp120-CD4 binding inhibitors of microbial origin, were isolated from a cultured broth of a soil fungus designated as Penicillium multicolor FO-2338 . These compounds were obtained as yellow powders from the cultured broth together with the known related compounds sclerotiorin, ochrephilone and rubrorotiorin . Isochromophilones I and II (C23H25O5Cl and C22H27O4Cl, respectively) have an azaphilone skeleton and a chlorine atom . Isochromophilones strongly inhibited gp120-CD4 binding (IC50: 6.6 and 3.9 microM, respectively), but the other related compounds did not . Isochromophilone II inhibited significantly HIV replication in peripheral human lymphocytes at 25 microM.

J Antibiot (Tokyo), 1995 Jul, 48(7), 568 - 73
Xenovulene A, a novel GABA-benzodiazepine receptor binding compound produced by Acremonium strictum; Ainsworth AM et al.; Xenovulene A, a novel inhibitor of benzodiazepine binding to the GABA-benzodiazepine receptor is produced by submerged fermentation of Acremonium strictum . It was isolated from the mycelium by solvent extraction and purified by chromatography on Sephadex LH-20 and octadecyl silica . The structure of xenovulene A was determined to be a novel oxygenated sesquiterpene containing a humulene moiety by interpretation of various spectroscopic data, especially from 2D NMR experiments . Xenovulene A inhibited binding of the benzodiazepine, flunitrazepam, with an IC50 of 40 nM in an in vitro assay using bovine synaptosome membrane preparations.

Plant Mol Biol, 1995 Jul, 28(4), 739 - 50
Aerobic fermentation in tobacco pollen; Bucher M et al.; We characterized the genes coding for the two dedicated enzymes of ethanolic fermentation, alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC), and show that they are functional in pollen . Two PDC-encoding genes were isolated, which displayed reciprocal regulation: PDC1 was anaerobically induced in leaves, whereas PDC2 mRNA was absent in leaves, but constitutively present in pollen . A flux through the ethanolic fermentation pathway could be measured in pollen under all tested environmental and developmental conditions . Surprisingly, the major factor influencing the rate of ethanol production was not oxygen availability, but the composition of the incubation medium . Under optimal conditions for pollen tube growth, approximately two-thirds of the carbon consumed was fermented, and ethanol accumulated into the surrounding medium to a concentration exceeding 100 mM.

Appl Microbiol Biotechnol, 1995 Jul, 43(3), 445 - 51
Efficient production of anti-(hepatitis B virus) antibodies and their neutralizing activity in chimpanzees; Sawada H et al.; For industrial production of human monoclonal antibodies (hmAb) against hepatitis B virus surface antigen (HBsAg), we scaled-up a short-term perfusion culture in serum-free medium, which was chosen as the most suitable culture method, to a 50-1 fermentor equipped with a rotating shear filter . Using hydrophobic chromatography as the initial step of hmAb purification, the mAb HBW4, HBW6 and W471 were isolated in good quality from the respective culture broths in yields of approximately 75% . Each of the three purified hmAb alone, and a cocktail of the three, protected chimpanzees against HB virus, when injected intravenously 3 h after viral challenge, as long as the serum antibody levels were significant . A pharmacokinetic study using cynomolgus monkeys demonstrated that the hmAb have a long plasma half-life and bioavailability of approximately 76% upon intramuscular injection in primates . Thus, anti-HBsAg hmAb produced by an industrial process are expected to be successfully used in clinical fields.

Appl Environ Microbiol, 1995 Jul, 61(7), 2732 - 7
Sudden substrate dilution induces a higher rate of citric acid production by Aspergillus niger; Legisa M et al.; On the basis of the present knowledge of Aspergillus niger metabolism during citric acid fermentation, an idea on how to improve the process was formed . Initially, a higher sucrose concentration was used for the germination of spores, which caused a higher intracellular level of the osmoregulator, glycerol, to be present . When citric acid started to be excreted into the medium, the substrate was suddenly diluted . Optimization of this procedure resulted in a nearly tripled volumetric rate (grams per liter per hour) of acid production, while the overall fermentation time was halved compared with the usual batch process . Yet, a characteristic delay was observed at the start of the acid excretion after the dilution . Hypo-osmotic shock caused a prominent elevation of intracellular cyclic AMP levels . Simultaneously, the specific activity of 6-phosphofructo-1-kinase increased significantly, probably due to phosphorylation of the protein molecule by cyclic AMP-dependent protein kinase . Specific 6-phosphofructo-1-kinase activity was much higher in the treated than in the normally growing mycelium . The metabolic flow through glycolysis was expected to be higher, which should contribute to a higher volumetric rate of acid production.

Comp Biochem Physiol A Physiol, 1995 Jul, 111(3), 433 - 8
The gastrointestinal tract of the rock hyrax (Procavia habessinica) . 2 . Fluid flow, production of short chain fatty acids and absorption of water and electrolytes; Bjornhag G et al.; In the digestive tract of the rock hyrax (Procavia habessinica), water is absorbed from the small intestine and from the wider part of the connecting colon running between the caecum and the colonic sac . Only little water absorption occurs from these two fermenting chambers . The outflow from the caecum is much higher than from the colonic sac mainly due to the effective absorption in the connecting colon with its very large absorptive area . A significant lower osmolality was found in the caecal contents compared with the contents in the colonic sac . The Na/K ratio was 10.7 and 1.7, respectively in these sections . Short chain fatty acids are produced at a rate of nearly 10 mmol/100 ml/hr in the contents of both the caecum and the colonic sac . The results are discussed in relation to the findings in domestic and laboratory animals.

Comp Biochem Physiol B Biochem Mol Biol, 1995 Jul, 111(3), 491 - 502
Comparative study and cDNA cloning of the flavoprotein subunit of mitochondrial complex II (succinate-ubiquinone oxidoreductase: fumarate reductase) from the dog heartworm, Dirofilaria immitis; Kuramochi T et al.; Mitochondrial complex II functions as a fumarate reductase (FRD), the reverse reaction of succinate dehydrogenase (SDH), and plays an important role in the anaerobic respiratory chain of parasitic helminths . In this study, complex II from the dog heartworm, Dirofilaria immitis adult, which is thought to act as a homolactatic fermenter, was examined in terms of its enzymatic features and primary structure in order to investigate the possible role of mitochondria in this filaria . Mitochondria from D . immitis adult showed high FRD activity when the enzymatic assay was performed using methylviologen as an artificial electron donor . The ratio of SDH to FRD in D . immitis was comparable to that in Ascaris suum adult, which is known to have an anaerobic mitochondrial respiratory chain with a high FRD activity of complex II . The FRD activity of D . immitis mitochondria was inhibited by the sulfhydryl reagent N-ethylmaleimide (NEM), while that of A . suum complex II was resistant to this inhibitor . The presence of the flavoprotein (Fp) subunit, which contains the substrate binding active site, was confirmed in D . immitis mitochondria by immunoblotting using a monoclonal antibody against the A . suum Fp subunit . By homology probing with the polymerase chain reaction, the entire cDNA for the D . immitis adult Fp was cloned and sequenced . The deduced amino acid sequence showed significant homology to that of A . suum and other mitochondrial Fps, in contrast to much less similarity to bacterial FRD, even though the D . immitis complex II showed high FRD activity . These results are the first indication of the presence of a functional complex II in D . immitis mitochondria.

J Dairy Sci, 1995 Jul, 78(7), 1512 - 25
Utilization of supplemental fat by dairy cows fed diets varying in content of nonstructural carbohydrates; Elliott JP et al.; Sixteen Jersey cows were used in a Latin square design to determine milk production and composition when the cows were fed supplemental fat in diets varying in nonstructural carbohydrate content . Eight cows were used in a second experiment to assess ruminal fermentation and nutrient digestibilities . Diets were 1) high nonstructural carbohydrates, no added fat; 2) high nonstructural carbohydrates, 2.5% added fat; 3) low nonstructural carbohydrates, no added fat; and 4) low nonstructural carbohydrates, 2.5% added fat . Diets consisted of alfalfa haylage, corn silage, and concentrate (22:22:56, DM basis) . Soyhulls replaced corn grain in diets 3 and 4; high and low diets contained 37.3 and 27.2% nonstructural carbohydrate . The DMI, milk production, and milk fat content were not affected by fat or nonstructural carbohydrates, although milk production tended to be higher when cows were fed fat . Fatty acid composition and N distribution of milk were unchanged by nonstructural carbohydrates . Supplemental fat decreased contents of CP, casein N, and true protein N in milk . Low nonstructural carbohydrates increased total VFA concentration and percentage of acetate and decreased percentages of propionate and butyrate in ruminal fluid . Total fatty acid digestibility decreased when cows were fed fat . Digestibilities of fiber components and total fatty acids were higher for diets low in nonstructural carbohydrates . Dietary content of nonstructural carbohydrates did not affect production of milk or milk components by Jersey cows fed supplemental fat.

J Anim Sci, 1995 Jul, 73(7), 2141 - 5
Effect of malate on in vitro mixed ruminal microorganism fermentation; Martin SA et al.; The objective of this study was to evaluate the effects of different concentrations of DL-malate (disodium salt) on the in vitro mixed ruminal microorganism fermentation of soluble starch or cracked corn . Ruminal fluid was collected from a steer fed 6.8 kg of forage and 2.3 kg of concentrate supplement once daily, and mixed ruminal microorganisms were incubated in anaerobic media (40 mL) that contained 20% (vol/vol) ruminal fluid in batch culture for 24 h at 39 degrees C . Malate was added to the incubation bottles (n = 4) to achieve final concentrations of 0, 4, 8, and 12 mM . When mixed ruminal microorganisms were incubated with only DL-malate as the substrate, final pH numerically increased, propionate and total VFA concentrations increased (P < .05), and the acetate:propionate ratio decreased (P < .05) as the concentration of DL-malate increased from 0 to 12 mM . Fermentation of cracked corn in the presence of 8 or 12 mM DL-malate resulted in an increase (P < .05) in final pH and propionate concentration . Total VFA tended to increase (P < .21), whereas final concentrations of L-lactate numerically decreased . In the case of soluble starch, 8 and 12 mM DL-malate caused a decrease (P < .05) in methane concentration . When only ruminal fluid (no added anaerobic medium) was used as the inoculum rather than 20% ruminal fluid medium, similar results for final pH, propionate, L-lactate, and total VFA were observed for soluble starch and corn incubations treated with DL-malate.(ABSTRACT TRUNCATED AT 250 WORDS)

Eur J Clin Nutr, 1995 Jul, 49(7), 484 - 91
Effect of acetate and propionate on fasting hepatic glucose production in humans; Laurent C et al.; OBJECTIVE: Short chain fatty acids (SCFA, e.g . acetate and propionate) produced from bacterial colonic fermentation may be involved in the improvement of fasting glucose concentration observed with high dietary fibre diets . Because fasting blood glucose is related to hepatic glucose production, we have tested the effect of propionate and acetate on hepatic glucose production . SETTING: The study was carried out in the Clinical Research Center for Human Nutrition . SUBJECTS: Six healthy young volunteers . INTERVENTIONS: The subjects received, in a random order: acetate (12 mmol/h), or propionate (4 mmol/h), or acetate+propionate (12 mmol/h + 4 mmol/h), or an isotonic sodium salt solution (saline) in 3 h gastric infusions . Blood glucose and plasma insulin was monitored . Hepatic glucose production was measured with an isotopic method using {6,6-2H2} glucose . RESULTS: No changes were observed in blood glucose, plasma insulin concentrations or hepatic glucose production with any of the infused solutions . An increase in free fatty acid (FFA) plasma concentration related to the fasting state was observed with the saline solution, but not with the SCFA infusions (P < 0.05) . There was also an increase in beta-hydroxybutyrate concentration with the saline and the acetate solutions, but not with the propionate or acetate+propionate solutions . CONCLUSIONS: SCFA, administered at a rate calculated on the basis of a continuous daily fermentation of 30 g dietary fibres, do not change hepatic glucose production or fasting blood glucose . Propionate and acetate decrease plasma FFA, and further studies are needed to explore this effect on glucose tolerance and insulin sensitivity.

Br Poult Sci, 1995 Jul, 36(3), 479 - 88
Nutritive activity of soluble rice brain arabinoxylans in broiler diets; Annison G et al.; 1 . A soluble material (703 g/kg non-starch polysaccharide, 141 g/kg starch and 166 g/kg protein) of low viscosity (termed RB-NSP), was isolated in large quantities from defatted Australian rice bran using a mild alkaline extraction and ethanol precipitation . 2 . The soluble non-starch polysaccharide fraction of RB-NSP comprised arabinose (0.40 mol%), xylose (0.32 mol%) galactose (0.17 mol%), glucose (0.08 mol%) and mannose (0.03 mol%) . 3 . RB-NSP was included at graded concentrations (0, 20, 40 and 60 g/kg) in a sorghum/casein basal diet and the diet fed to male broilers in a classical balance trial to determine apparent metabolisable energy (AME) . The AME values recorded were 13.26, 13.85, 14.26 and 14.00 MJ/kg DM with a significant correlation (r = 0.65, P < 0.001) between dietary RB-NSP inclusion rate and dietary AME . 4 . Feeding RB-NSP had no effect on growth, food conversion ratio or the digestibilities of starch and protein which were both high (0.98-0.99 and 0.88-0.89, respectively) . 5 . It was concluded that the RB-NSP may have been a substrate for hindgut fermentation in the broiler but that it possessed no anti-nutritive activity.

Eur J Cancer, 1995 Jul-Aug, 31A(7-8), 1077 - 80
Role of short-chain fatty acids in the prevention of colorectal cancer; Scheppach W et al.; Short-chain fatty acids (SCFAs: acetate, propionate, n-butyrate) arising in the large bowel during bacterial fermentation of dietary fibre and starch have paradoxical effects on colonic epithelial proliferation . While the three major SCFAs stimulate proliferation of normal crypt cells, n-butyrate and, to a lesser degree, propionate inhibit growth of colon cancer cell lines . At the molecular level, n-butyrate causes histone acetylation, favours differentiation, induces apoptosis and regulates the expression of various oncogenes . To understand the complex effects of SCFAs on carcinogenesis, it is important to study the intermediate stages of the adenoma-carcinoma sequence where a "switch" from stimulation to suppression of cell proliferation must occur.

Eur J Cancer, 1995 Jul-Aug, 31A(7-8), 1033 - 8
Risk factors for colon neoplasia--epidemiology and biology; Potter JD; Epidemiological, physiological and molecular models of colon carcinogenesis have been proposed . Consistent epidemiological risk factors include reduced plant-food intake (increased risk); elevated meat intake (increased risk); higher physical activity (reduced risk); and increased alcohol intake (increased risk) . At the physiological level, these lifestyle variables may trigger processes that provide explanations for the associations: higher meat, fat and alcohol means more heterocyclic amines and higher levels of bile acids; higher plant food means higher intake of several anticarcinogens and fibre fermentation that produces volatile fatty acids; exercise has a variety of beneficial effects . This complexity is elaborated further in the context of the colonic milieu where interactions among digesta, bacteria and epithelial cells occur . The long-term likelihood of cancer is the summation of moment-to-moment changes in the colonic milieu brought about by this interaction . Possible relationships between established epidemiological risk factors, genetic susceptibility and somatic genetic changes are outlined.

Crit Rev Food Sci Nutr, 1995 Jul, 35(4), 299 - 339
Cyanide detoxification in cassava for food and feed uses; Padmaja G; Cassava (Manihot esculenta Crantz) is an important tropical root crop providing energy to about 500 million people . The presence of the two cyanogenic glycosides, linamarin and lotaustralin, in cassava is a major factor limiting its use as food or feed . Traditional processing techniques practiced in cassava production are known to reduce cyanide in tubers and leaves . Drying is the most ubiquitous processing operation in many tropical countries . Sun drying eliminates more cyanide than oven drying because of the prolonged contact time between linamarase and the glucosides in sun drying . Soaking followed by boiling is better than soaking or boiling alone in removing cyanide . Traditional African food products such as gari and fufu are made by a series of operations such as grating, dewatering, fermenting, and roasting . During the various stages of gari manufacture, 80 to 95% cyanide loss occurs . The best processing method for the use of cassava leaves as human food is pounding the leaves and cooking the mash in water . Fermentation, boiling, and ensiling are efficient techniques for removing cyanide from cassava peels.

J Nat Prod, 1995 Jul, 58(7), 986 - 91
Barceloneic acid A, a new farnesyl-protein transferase inhibitor from a Phoma species; Jayasuriya H et al.; Three new diphenyl ethers, barceloneic acids A, B, and barceloneic lactone {1, 2, and 3, respectively} were isolated from a fermentation extract of a fungus of the genus Phoma . The structures of compounds 1-3 were determined by a combination of spectroscopic and single-crystal X-ray diffraction methods . The effect of these compounds on the inhibition of farnesyl-protein transferase (FPTase) was evaluated and results are presented . Barceloneic acid A {1} is a novel and modest inhibitor of FPTase with an IC50 value of 40 microM.

Microbiology, 1995 Jul, 141 ( Pt 7), 1567 - 74
Coordination of sucrose uptake and respiration in the yeast Debaryomyces yamadae; Kaliterna J et al.; Screening in batch cultures identified Debaryomyces yamadae as a yeast that exhibits the Kluyver effect for sucrose: this disaccharide can be respired but, even under oxygen-limited conditions, alcoholic fermentation of sucrose does not occur . Ethanol, glycerol and arabitol were the main fermentation products during oxygen-limited growth on glucose in chemostat cultures . None of these fermentation products were produced in oxygen-limited chemostat cultures grown on sucrose and the fraction of the sucrose that could not be respired remained unused in the culture medium . This absence of alcoholic fermentation was not due to repression of the key fermentative enzymes pyruvate decarboxylase and alcohol dehydrogenase . In contrast to some other yeasts that exhibit a Kluyver effect, D . yamadae did not exhibit a preference for ethanol in batch cultures grown on mixtures of ethanol and sucrose . Sucrose metabolism in D . yamadae involves intracellular hydrolysis by an alpha-glucosidase . Incubation of weakly buffered cell suspensions with sucrose led to a rapid transient alkalinization, indicating the presence of a sucrose-proton symport system . The apparent substrate saturation constant of the sucrose-uptake system was 0.2 mmol l-1 . Sucrose-dependent alkalinization rates were much lower in samples from oxygen-limited cultures than in samples from aerobic cultures . Transient responses of D . yamadae to oxygen limitation were investigated by applying a sudden decrease in the oxygen feed to aerobic sugar-limited chemostat cultures . In glucose-grown cultures, this led to alcoholic fermentation and no significant accumulation of sugar occurred after the switch . In sucrose-limited cultures, sugar accumulation occurred instantaneously after the switch, and ethanol formation was virtually absent.(ABSTRACT TRUNCATED AT 250 WORDS)

Adv Dent Res, 1995 Jul, 9(2), 106 - 9
Can prevention eliminate caries?
O'Mullane D.
There are four main factors involved in the carious process: at-risk tooth structure, plaque flora, fermentable carbohydrates, and time . Based on our knowledge of the carious process, four main preventive strategies have been developed over the years, namely, fluorides, fissure sealing, dietary choice, and plaque control . Fluorides are having a major impact on smooth-surface caries; hence, strategies combining fluorides and fissure sealing are very effective . However, use of fissure sealing is still problematic . Changing dietary practices with a view to reducing dental caries seems to be having little impact on a global scale . Plaque control, as practiced routinely by the majority of people, is not sufficient to result in caries reductions . Deprivation and poverty are strongly associated with high caries levels . Although the preventive strategies currently available are likely to result in lower caries levels for many, for logistical reasons and because of factors associated with deprivation and poverty, caries is likely to remain a major public health problem in most communities for the foreseeable future.

Mol Microbiol, 1995 Jul, 17(1), 95 - 107
Cloning and characterization of GPD2, a second gene encoding sn-glycerol 3-phosphate dehydrogenase (NAD+) in Saccharomyces cerevisiae, and its comparison with GPD1; Eriksson P et al.; We have cloned and characterized a homologue of the previously isolated GPD1 gene, encoding sn-glycerol 3-phosphate dehydrogenase (NAD+) in Saccharomyces cerevisiae . This second gene, called GPD2, encodes a protein of 384 amino acids that shares 69% sequence identity with GPD1 . Like GPD1 it has an amino-terminal extension of unknown function . GPD2 is located on chromosome VII and cross-hybridizes with GPD1 at chromosome IV as well as with an unknown homologue at chromosome XV . Disruption of the GPD2 gene did not reveal any observable phenotypic effects, whereas overexpression resulted in a slight, but significant, increase of GPD enzyme activity in wild-type cells . Analysis of gene transcription by a CAT-reporter gene fused to the GPD promoters revealed decreased transcriptional activity of the GPD2 promoter in cells grown on nonfermentable as opposed to fermentable carbon sources, and no induction in cells exposed to high osmolarity or heat shock . Similar analysis of GPD1 demonstrated an 8-17-fold higher basal level of transcription compared to GPD2 . Furthermore, such analysis revealed that the GPD1 promoter was induced by increased osmolarity essentially independent of the type of stress solute used, the level of GPD1 transcription being increased about sevenfold in cells growing at 1.4 M NaCl.

Mol Microbiol, 1995 Jul, 17(1), 109 - 21
tRNA genes and pathogenicity islands: influence on virulence and metabolic properties of uropathogenic Escherichia coli; Ritter A et al.; The uropathogenic Escherichia coli strain 536 (O6:K15:H31) carries two unstable DNA regions on its chromosome which were termed pathogenicity islands (Pais) . Both pathogenicity islands, Pai I and Pai II, are incorporated into tRNA specific loci: Pai I is located in the tRNA gene for selenocysteine (selC), and Pai II is integrated in the leucine-specific tRNA locus leuX . Mutant strain 536-21 has lost the two pathogenicity islands together with the intact tRNA genes . While 536 is a virulent strain, 536-21 has lost a number of properties, including in vivo virulence . In previous publications we reported that the genes coding for two haemolysins (hly I, hly II) and P-related fimbria (prf) are located on the Pais . In this paper, we demonstrate that the expression of other gene products influencing metabolic properties in addition to in vivo virulence are strongly dependent on the intact tRNA loci selC and leuX . In order to determine the influence of the two tRNAs on the expression of these properties, the genes selC and leuX were cloned from the genome of strain 536 and then introduced into the mutant 536-21 . Our results clearly show that the seleno-cysteine-specific tRNA (tRNA(Sec)) directly influences the ability of the bacteria to grow under anaerobic conditions, because selenocysteine is part of the enzyme formate dehydrogenase (FDH) which is involved in mixed acid fermentation . The rare leucine-specific tRNA5(Leu), encoded by leuX, influences a number if properties including type 1 fimbria production, flagellation and motility, production of enterobactin and serum resistance, and is also necessary for full in vivo virulence . While the tRNA(Sec) is directly involved in the production of FDHs, the leuX specific tRNA5(Leu) appears to influence the expression of various factors through specific transcriptional or translational control mechanisms.

Yeast, 1995 Jun 30, 11(8), 735 - 45
Localization of the dominant flocculation genes FLO5 and FLO8 of Saccharomyces cerevisiae; Teunissen AW et al.; In the yeast Saccharomyces cerevisiae three dominant flocculation genes, FLO1, FLO5 and FLO8 have been described . Until now only the FLO1 gene, which is located at chromosome I, has been cloned and sequenced . FLO5 and FLO8 were previously localized at chromosomes I and VIII respectively (Vezinhet, F., Blondin, B . and Barre, P . (1991) . Mapping of the FLO5 gene of Saccharomyces cerevisiae by transfer of a chromosome during cytoduction . Biotechnol . Lett . 13, 47-52; Yamashita, I . and Fukui, S . (1983) . Mating signals control expression of both starch fermentation genes and a novel flocculation gene FLO8 in the yeast Saccharomyces . Agric . Biol . Chem . 47, 2889-2896) . This was not in agreement with our results . Here, we report the location of FLO5 and FLO8 on chromosomes VIII and I respectively . By induced chromosome loss and genetic mapping, the FLO5 gene was localized at the right end of chromosome VIII approximately 34 cM centromere distal of PET3 . This is part of the region that is present both at chromosome I and chromosome VIII . The location of FLO5 in this area of chromosome VIII made it necessary to re-evaluate the localization of FLO8, which was previously thought to occur in this region . Both genetic and physical mapping showed that FLO8 is allelic to FLO1 . Hence, there are only two known dominant flocculation genes, FLO1 and FLO5 . Analysis of the nucleotide sequence of chromosome VIII of a non-flocculent strain revealed an open reading frame encoding a putative protein that is approximately 96% identical to the Flo1 protein . This suggests that both dominant flocculation genes encode similar, cell wall-associated, proteins with the same function in the flocculation mechanism.

J Chromatogr A, 1995 Jun 23, 705(1), 155 - 61
Analysis of recombinant human growth hormone in Escherichia coli fermentation broth by micellar high-performance liquid chromatography; Strege MA et al.; A method for the reversed-phase high-performance liquid chromatographic (HPLC) determination of recombinant methionylaspartyl-human growth hormone (MD-HGH) in Escherichia coli fermentation broth is described . The technique utilizes mobile phases containing n-propanol and the anionic surfactant sodium dodecyl sulfate (SDS) under micellar conditions at pH 6.4 . The methodology is directly applicable to the analysis of samples solubilized via sulfitolysis in the presence of SDS, and offers superior resolution in comparison with chromatography in the absence of the surfactant . Using this method, acceptable precision (day-to-day R.S.D . = 4.9%), accuracy, selectivity, range, linearity and ruggedness were achieved.

Nature, 1995 Jun 22, 375(6533), 700 - 4
Crystal structure of isopenicillin N synthase is the first from a new structural family of enzymes; Roach PL et al.; Penicillin antibiotics are all produced from fermentation-derived penicillins because their chemical synthesis is not commercially viable . The key step in penicillin biosynthesis, in which both the beta-lactam and thiazolidine rings of the nucleus are created, is mediated by isopenicillin N synthase (IPNS), which binds ferrous iron and uses dioxygen as a cosubstrate . In a unique enzymatic step, with no chemical precedent, IPNS catalyses the transfer of four hydrogen atoms from its tripeptide substrate to dioxygen forming, in a single reaction, the complete bicyclic nucleus of the penicillins . We now report the structure of IPNS complexed with manganese, which reveals the active site is unusually buried within a 'jelly-roll' motif and lined by hydrophobic residues, and suggest how this structure permits the process of penicillin formation . Sequence analyses indicate IPNS, 1-aminocyclopropane-1-carboxylic acid oxidase and many of the 2-oxo-acid-dependent oxygenases contain a conserved jelly-roll motif, forming a new structural family of enzymes.

J Am Coll Nutr, 1995 Jun, 14(3), 229 - 32
Sulfite sensitivity: significance in human health; Lester MR; Endogenous sulfite is generated as a consequence of the body's normal processing of sulfur-containing amino acids . Sulfites occur as a consequence of fermentation and also occur naturally in a number of foods and beverages . As food additives, sulfiting agents were first used in 1664 and approved in the United States as long ago as the 1800s . With such long experience with their use, it is easy to understand why these substances have been regarded as safe . They are currently used for a variety of preservative properties, including controlling microbial growth, preventing browning and spoilage, and bleaching some foods . It is estimated that up to 500,000 (< .05% of the population) sulfite-sensitive individuals live in the United States . Sulfite sensitivity occurs most often in asthmatic adults--predominantly women; it is uncommonly reported in preschool children . Adverse reactions to sulfites in nonasthmatics are extremely rare . Asthmatics who are steroid-dependent or who have a higher degree of airway hyperreactivity may be at greater risk of experiencing a reaction to sulfite-containing foods . Even within this limited population, sulfite sensitivity reactions vary widely, ranging from no reaction to severe . The majority of reactions are mild . These manifestations may include dermatologic, respiratory, or gastrointestinal signs and symptoms . Severe nonspecific signs and symptoms occur less commonly . Broncho-constriction is the most common sensitivity response in asthmatics . The precise mechanisms of the sensitivity responses have not been completely elucidated . Inhalation of sulfur dioxide (SO2) generated in the stomach following ingestion of sulfite-containing foods or beverages, a deficiency in a mitochondrial enzyme, and an IgE-mediated immune response have all been implicated.(ABSTRACT TRUNCATED AT 250 WORDS)

Plant Foods Hum Nutr, 1995 Jun, 47(4), 319 - 26
The nutritive quality of maize-soybean (70:30) tempe flour; Tchango Tchango J; The nutritive quality of maize-soybean (70:30) tempe flour manufactured by fermentation with Rhizopus oligosporus: Rhizopus orysae (1:1) was determined using weanling rats . Mould fermentation of maize-soybean mixture did not significantly affect its proximate composition . It increased the content of reducing sugars, total acids and aminonitrogen by about 43, 195 and 482 percent, respectively, and decreased phytate content by 46 percent . In vitro iron absorption for maize flour and maize-soybean tempe flour was 2.46 and 5.51 percent, respectively . Protein Efficiency Ratio (PER) and Net Protein Ratio (NPR) for maize-soybean tempe flour and skim-milk diets were 2.71 and 2.96, respectively, for PER, and 3.31 and 3.51, respectively, for NPR . In vivo protein digestibility of the two products was 95.0 and 98.0 percent, respectively.

Plant Foods Hum Nutr, 1995 Jun, 47(4), 293 - 9
Effects of processing and in vitro proteolytic digestion on soybean and yambean hemagglutinins; Ojimelukwe PC et al.; Some conventional processing methods were applied on yambean and soybean seeds and flour samples . They include soaking fermentation, cooking whole seeds in the presence and absence of trona, autoclaving and dry heat treatment of flour samples . Hemagglutinating activity was assayed for after processing treatments . The hemagglutinating proteins from these seeds were classified based on their solubility properties . Effects of the presence of 0.01% concentration of trypsin, pepsin and proteases on agglutination of human red blood cells were also evaluated . Most processing methods, particularly cooking whole seeds for 1-2 h, soaking and fermentation, reduced hemagglutinating activity on cow red blood cells . Size reduction accompanied by heat treatment was effective in eliminating hemagglutination . Both the albumin and globulin fractions of the soybean showed hemagglutinating activity but only the albumin fraction of the yambean had agglutinating properties . Proteolytic action of proteases was more effective in reduction of hemagglutinating activity than that of trypsin and pepsin.

Mol Microbiol, 1995 Jun, 16(6), 1157 - 69
The global regulatory protein FruR modulates the direction of carbon flow in Escherichia coli; Ramseier TM et al.; The Escherichia coli fructose repressor, FruR, is known to regulate expression of several genes concerned with carbon utilization . Using a previously derived consensus sequence for FruR binding, additional potential operators were identified and tested for FruR binding in DNA band migration retardation assays . Operators in the control regions of operons concerned with carbon metabolism bound FruR, while those in operons not concerned with carbon metabolism did not . In vivo assays with transcriptional lacZ fusions showed that FruR controls the expression of FruR operator-containing genes encoding key enzymes of virtually every major pathway of carbon metabolism . Moreover, a fruR null mutation altered the rates of utilization of at least 36 carbon sources . In general, oxidation rates for glycolytic substances were enhanced while those for gluconeogenic substances were depressed . Alignment of FruR operators revealed that the consensus sequence for FruR binding is the same for operons that are activated and repressed by FruR and permitted formulation of a revised FruR-binding consensus sequence . The reported observations indicate that FruR modulates the direction of carbon flow by transcriptional activation of genes encoding enzymes concerned with oxidative and gluconeogenic carbon flow and by repression of those concerned with fermentative carbon flow.

J Pharm Biomed Anal, 1995 Jun, 13(7), 809 - 16
The analysis of aminoglycoside antibiotics by capillary electrophoresis; Flurer CL; The analyses of aminoglycoside antibiotics by capillary electrophoresis utilizing borate complexation and direct UV detection are discussed . Twelve aminoglycosides were studied and separated to demonstrate identification capabilities, with migration time RSDs from 0.21 to 0.44% (n = 6) for individual components . This buffer system permitted the detection of minor impurities such as precursors or closely related fermentation products . Quantification of dihydrostreptomycin and streptomycin was accomplished in 160 mM sodium tetraborate decahydrate with linearity over the range 0.050-1.0 mg ml-1 . Determination of the purity of bulk dihydrostreptomycin was possible by the addition of the cationic surfactant myristyltrimethylammonium bromide . This reversed the electroosmotic flow, thereby reversing the migration order, and causing the streptomycin impurity to migrate before the dihydrostreptomycin main peak . Quantification was also demonstrated with the closely related compounds amikacin, bekanamycin, kanamycin A, and tobramycin, using sisomicin as an internal standard . The reproducibility of the method was typically 2-3% over 1 day, and 2% day-to-day . These studies illustrate the use of capillary electrophoresis for the identification and quantification of selected aminoglycosides as potential alternative methods to the assays given by the US Pharmacopeia.

Appl Environ Microbiol, 1995 Jun, 61(6), 2431 - 5
Rapid large-scale growth of Helicobacter pylori in flasks and fermentors; Deshpande M et al.; We developed procedures for large-scale cultivation of Helicobacter pylori in flasks and fermentors . Flasks incubated closed under a microaerophilic gas phase with a cotton plug covered by a plastic bag, followed by removal of the bag after 8 h, gave excellent growth . Growth in a 10-liter fermentor led to excessive foaming if the medium was sparged with gas; silicone- or polyglycol-based antifoaming agents were severely inhibitory . Use of fermentor surface gassing, first with a microaerophilic 6% oxygen gas mixture, then with air, and then with 95% oxygen, allowed the culture to grow to an A600 of 2.5 in < 24 h . This method was modified for scale-up to a 100-liter fermentor.

Appl Environ Microbiol, 1995 Jun, 61(6), 2132 - 8
Fe(III) and S0 reduction by Pelobacter carbinolicus; Lovley DR et al.; There is a close phylogenetic relationship between Pelobacter species and members of the genera Desulfuromonas and Geobacter, and yet there has been a perplexing lack of physiological similarities . Pelobacter species have been considered to have a fermentative metabolism . In contrast, Desulfuromonas and Geobacter species have a respiratory metabolism with Fe(III) serving as the common terminal electron acceptor in all species . However, the ability of Pelobacter species to reduce Fe(III) had not been previously evaluated . When a culture of Pelobacter carbinolicus that had grown by fermentation of 2,3-butanediol was inoculated into the same medium supplemented with Fe(III), the Fe(III) was reduced . There was less accumulation of ethanol and more production of acetate in the presence of Fe(III) . P . carbinolicus grew with ethanol as the sole electron donor and Fe(III) as the sole electron acceptor . Ethanol was metabolized to acetate . Growth was also possible on Fe(III) with the oxidation of propanol to propionate or butanol to butyrate if acetate was provided as a carbon source . P . carbinolicus appears capable of conserving energy to support growth from Fe(III) respiration as it also grew with H2 or formate as the electron donor and Fe(III) as the electron acceptor . Once adapted to Fe(III) reduction, P . carbinolicus could also grow on ethanol or H2 with S0 as the electron acceptor . P . carbinolicus did not contain detectable concentrations of the c-type cytochromes that previous studies have suggested are involved in electron transport to Fe(III) in other organisms that conserve energy to support growth from Fe(III) reduction.(ABSTRACT TRUNCATED AT 250 WORDS)

J Med Microbiol, 1995 Jun, 42(6), 421 - 8
Antibiotic susceptibility of Mycoplasma fermentans strains from various sources and the development of resistance to aminoglycosides in vitro; Hannan PC; Mycoplasma fermentans strains reputedly from human infections or tissue culture cells were much more susceptible to azithromycin than to clarithromycin or erythromycin . Lincomycin, clindamycin and several tetracyclines also exhibited good mycoplasmastatic activity but mycoplasmacidal concentrations were substantially greater than the MICs . Ciprofloxacin was the most active of three fluoroquinolones tested and was mycoplasmacidal at concentrations close to the MIC . Tiamulin and mupirocin were also very active . Synergy with specific M . fermentans antiserum plus guinea-pig complement was not observed with any class of antibiotic although the number of viable mycoplasmas was markedly reduced by the combined immunological components . Marked differences in susceptibility to various aminoglycosides were observed . Human strains isolated in cell-free media up to 1967 were aminoglycoside susceptible (MIC range 0.5-25 mg/L) but recent human isolates and strains isolated from tissue culture cells often showed either single or multiple aminoglycoside resistance (MIC > 500 mg/L) . Two aminoglycoside-susceptible strains developed resistance to streptomycin or neomycin (> 500 mg/L) within five passages in broth containing streptomycin or neomycin, respectively . Resistance to tobramycin, kanamycin or gentamicin emerged after seven, eight and 14 cycles of exposure to the respective antibiotic . Streptomycin resistance was associated with a five-fold increase in resistance to tobramycin . Neomycin-, kanamycin-, gentamicin- and tobramycin-resistant variants showed mutual cross-resistance but remained susceptible to streptomycin . Induced resistance persisted for at least 17 passages in aminoglycoside-free broth . The use of aminoglycosides in human medicine and the frequent inclusion of some of these drugs in tissue cell cultures to combat bacterial and mycoplasmal contamination might account for the aminoglycoside resistance of recent M . fermentans isolates.

J Nutr, 1995 Jun, 125(6), 1554 - 62
Inhibition of starch digestion by alpha-amylase inhibitor reduces the efficiency of utilization of dietary proteins and lipids and retards the growth of rats; Pusztai A et al.; Digestion/absorption and nutritional utilization of starch, protein and lipids were studied in rats fed diets containing purified kidney bean alpha-amylase inhibitor at levels of 0, 1.6, 3.3 and 6.6 g/kg diet . At the two higher levels, the growth rate of rats and the apparent digestibilities and utilization of dietary starch and protein were significantly less than in control rats, and losses of nitrogen, lipids and carbohydrate resulted in a significant reduction in dry body weight . Some organs of the body were also affected: the relative dry weights of the intestines and the pancreas were higher, whereas liver and thymus weights were lower than in control rats . As starch digestion in the small intestine was negligible at higher inhibitor concentrations, the cecum was practically blocked by solidified digesta . This effect and the ensuing bacterial fermentation stimulated the growth of this tissue by hyperplasia and hypertrophy . However, as the distension was not always sufficient, the organ was occasionally ruptured and the rats had to be killed . Inhibitor doses in this work were comparable to those in clinical studies, implying that the use of the inhibitor is not without health risks . Moreover, diets rich in alpha-amylase inhibitor such as those containing transgenic plants with high levels of inhibitor gene expression cannot be recommended in intensive animal production.

J Nutr, 1995 Jun, 125(6), 1503 - 11
Sourdough fermentation or addition of organic acids or corresponding salts to bread improves nutritional properties of starch in healthy humans; Liljeberg HG et al.; Postprandial blood glucose and insulin responses to barley bread containing organic acids or corresponding salts were evaluated in healthy human subjects . The satiety score and the rate and extent of in vitro starch digestion were also studied . Lactic acid was generated by use of a homofermentative starter culture or added to the dough . In addition, products were baked with Ca-lactate, or with Na-propionate at two different concentrations . Consumption of the product baked with a high concentration of Na-propionate significantly lowered the postprandial blood glucose and insulin responses, and significantly prolonged the duration of satiety compared with all other breads . When subjects consumed the breads baked with sourdough, lactic acid and Na-propionate, their glucose and insulin responses were reduced compared with the wholemeal bread alone . The rate of in vitro amylolysis was reduced only by ingestion of the breads containing lactic acid, suggesting that the beneficial impact of Na-propionate on metabolic responses and satiety was related to effects other than a reduced rate of starch hydrolysis . All bread products had a similar concentration of in vitro resistant starch of 1.3-2.1 g/100 g (starch basis) . It is concluded that sourdough baking and other fermentation processes may improve the nutritional features of starch . The results also demonstrate that certain salts of organic acids may have metabolic effects.

Gastroenterology, 1995 Jun, 108(6), 1745 - 52
The effects of and interactions between fermentable dietary fiber and lipid in germfree and conventional mice; Pell JD et al.; BACKGROUND/AIMS: Dietary fiber can stimulate intestinal epithelial cell proliferation . The aim of this study was to resolve the different roles of fermentation and intraluminal viscosity on this trophic action and to investigate reported interactions between fiber and dietary fat . METHODS: Conventional and germfree mice were fed guar gum in combination with low- or high-lipid diets for 2 weeks, and crypt cell production rates were determined . RESULTS: Guar gum significantly stimulated proliferation in the small intestine, especially when combined with fat . Lipid itself also stimulated proliferation in the small intestine and had a direct trophic effect in the cecum and colon of the germfree mice . Fiber markedly stimulated proliferation in the cecum and colon but only in the conventional group . Interactions between lipid and bacteria and between guar gum and bacteria were also observed in the small intestine . CONCLUSIONS: Guar gum has a trophic effect in the small bowel, probably related to viscosity, in addition to its fermentation-related actions in the colon . Positive interaction with lipid may be associated with delayed absorption . Lipid also has its own direct actions on small bowel mucosal proliferation, which are attenuated by the presence of bacteria.

Am J Clin Nutr, 1995 Jun, 61(6), 1241 - 7
Propionate inhibits incorporation of colonic {1,2-13C}acetate into plasma lipids in humans; Wolever TM et al.; Acetate and propionate, produced during colonic fermentation of unabsorbed carbohydrate, may influence systemic lipid metabolism . As a preliminary study to see whether colonic acetate is incorporated into plasma lipids and whether propionate inhibits this process, 5 healthy males were studied after fasting overnight . They were given, in random order, 12.5 mmol (1.05 g) {1,2-13C}sodium acetate by intravenous or rectal infusion, and the rectal infusion was given with or without 6 mmol (0.58 g) sodium propionate . Two hours after rectal acetate, 13C recoveries in plasma cholesterol (0.59 +/- 0.22%) and triglycerides (1.24 +/- 0.69%) were significantly greater than after intravenous acetate (0.09 +/- 0.12% and 0.29 +/- 0.18%, respectively) . Addition of propionate reduced 13C recovery in triglycerides (0.19 +/- 0.06%, P = 0.024) compared with rectal acetate alone, but the effect on cholesterol (0.26 +/- 0.05%) was not significant . These data suggest that incorporation of colonic acetate into plasma triglycerides is inhibited by propionate . Further studies are required to quantify the effects of colonic acetate and propionate on lipid synthesis.

Mol Cell Biol, 1995 Jun, 15(6), 3382 - 9
The mitochondrial receptor complex: Mom22 is essential for cell viability and directly interacts with preproteins; Honlinger A et al.; A multisubunit complex in the mitochondrial outer membrane is responsible for targeting and membrane translocation of nuclear-encoded preproteins . This receptor complex contains two import receptors, a general insertion pore and the protein Mom22 . It was unknown if Mom22 directly interacts with preproteins, and two views existed about the possible functions of Mom22: a central role in transfer of preproteins from both receptors to the general insertion pore or a more limited function dependent on the presence of the receptor Mom19 . For this report, we identified and cloned Saccharomyces cerevisiae MOM22 and investigated whether it plays a direct role in targeting of preproteins . A preprotein accumulated at the mitochondrial outer membrane was cross-linked to Mom22 . The cross-linking depended on the import stage of the preprotein . Overexpression of Mom22 suppressed the respiratory defect of yeast cells lacking Mom19 and increased preprotein import into mom19 delta mitochondria, demonstrating that Mom22 can function independently of Mom19 . Overexpression of Mom22 even suppressed the lethal phenotype of a double deletion of the two import receptors known so far (mom19 delta mom72 delta) . Deletion of the MOM22 gene was lethal for yeast cells, identifying Mom22 as one of the few mitochondrial membrane proteins essential for fermentative growth . These results suggest that Mom22 plays an essential role in the mitochondrial receptor complex . It directly interacts with preproteins in transit and can perform receptor-like activities.

J Anim Sci, 1995 Jun, 73(6), 1819 - 27
Effects of protein source on nitrogen metabolism in continuous culture and intestinal digestion in vitro; Calsamiglia S et al.; Eight dual flow continuous culture fermenters were used in four replicated periods to study the effects of protein supplements on ruminal fermentation and CP digestion . A basal diet was supplemented with isonitrogenous amounts of urea and tryptone (control; CTRL), soybean meal (SBM), lignosulfonate-treated SBM (LSBM), corn gluten meal (CGM), blood meal (BM), hydrolyzed feather meal (HFM), fish meal (FM), or meat and bone meal (MBM) . Digestion of DM, OM, and carbohydrates was not affected by treatment . Ammonia N concentration was highest (P < .05) for CTRL and lowest (P < .05) for LSBM, CGM, BM, HFM, and FM . Nonammonia N flow was lowest (P < .05) for CTRL . Dietary N flow was lowest (P < .05) for CTRL, intermediate for SBM, and highest (P < .05) for LSBM, CGM, BM, HFM, FM, and MBM . Total N flow, bacterial N flow, and efficiency of microbial protein synthesis were not affected by treatment . Protein degradation was highest (P < .05) for CTRL . Flow of total amino acids (AA) was lowest (P < .05) for CTRL, SBM, and MBM . Diets containing BM provided the largest (P < .05) amounts of essential AA and lysine, and FM provided the largest (P < .05) amounts of methionine in fermenter effluent . Supplementation of diets with proteins low in ruminal degradability increased flows of nonammonia N, dietary N, and total and essential AA and modified the AA profile flowing out of fermenters.

J Ind Microbiol, 1995 Jun, 14(6), 514 - 22
Facts, myths and legends on the prime industrial microorganism; Vaughan-Martini A et al.; Archaic speculations and firmly established legends regarding the origin of the yeast Saccharomyces cerevisiae and related species are revisited in light of past and recent ecological evidence pointing to a strict association with artificial, man-made environments such as wineries and fermentation plants . The nomenclature within this industrially important group is also discussed in view of the modifications imposed from application of molecular techniques to classification.

Br J Nutr, 1995 Jun, 73(6), 897 - 913
Formation of complexes between polyvinyl pyrrolidones or polyethylene glycols and tannins, and their implication in gas production and true digestibility in in vitro techniques; Makkar HP et al.; Various tannin-complexing agents have been used to study the potential adverse effects of tannins on rumen metabolism . Using a method based on turbidity formation, the binding of various tannin-complexing agents (polyvinyl polypyrrolidone (PVPP), polyethylene glycol (PEG) of molecular weights 2000 to 35,000, and polyvinyl pyrrolidone (PVP) of molecular weight 10,000, 40,000 and 360,000) to tannins (tannic acid, purified tannins from quebracho (Aspidosperma quebracho) and leaves of trees and shrubs (Acioa barteri, Dichostachys cinerea, Guiera senegalensis, Piliostigma reticulatum)) was investigated at different pH values . The binding of all the tannins with PVPP was highest at pH 3-4 and lowest at pH 7 . For all the pH range (3-7) studied, the binding of PEG was higher than that of PVP . For all the tannins except tannic acid, the binding to PVP was the same from pH 4.7 to 7 . Similar results were observed for the PEG of molecular weight 6000 or higher for all the tannins except quebracho tannins for which the binding increased as the pH increased from 3 to 7 . The binding with PEG 2000 decreased to a greater extent as the pH reached near neutral and for PEG 4000 this decrease was slightly lower . Addition of these tannin-complexing agents to the in vitro gas system resulted in higher gas production from tannin-rich feeds (increase varied from 0 to 135%) . The PEG were the most effective followed by PVP and PVPP . The PEG 35,000 was least effective . The efficiency of other PEG was similar . The PEG 6000 was preferred to PEG 2000 or 4000 as its binding to tannins was higher at near neutral pH values . The gas production increased with an increase in the amount of PEG 6000 up to 0.6 g/40 ml rumen-fluid-containing medium containing 0.5 g tannin-rich feed, beyond which no increase was observed . The percentage increase in gas value at 24 h fermentation correlated significantly with tannin values, the highest correlation (r 0.95) being with protein precipitation capacity of tannins . The increase in gas production was associated with higher production of short-chain fatty acids with little change in their molar proportions, suggesting an increase in organic matter digestibility by inclusion of the PEG in tannin-rich feeds . However, apparent and true digestibilities were lower on addition of the PEG, due to the presence of PEG-tannin complexes in the residues . The use of this bioassay (percentage increase in gas production in the presence of PEG 6000) along with other tannin assays would provide a better insight into the nutritional significance of tannins.

Nippon Eiseigaku Zasshi, 1995 Jun, 50(2), 604 - 15
{A study on the effects of physical load on high school baseball players during midsummer games}; Kurakake S et al.; This study attempted to measure the physical load on high school baseball players during games played under extremely hot and humid conditions in the summer . The factors used to determine physical load were the following: body weight, oral temperature, blood pressure, heart rate, and serum biochemical elements . These were measured before and after the game . One hundred twenty-six baseball players from 7 high schools participated in this study . All the games were played under conditions of high temperature 34 degrees Celsius dry-bulb, 26 degrees Celsius wet-bulb, 41 degrees Celsius black-globe, 30 degrees WBGT, which are likely to cause heat-related illnesses . The results were as follows . 1) The physical load of baseball players during the game showed a 1.8 percent decrease in average body weight due to perspiration, a 0.35 degrees C increase in oral temperature and an increase in the heart rate . Examination of the serum biochemical elements showed that muscle deviation ferment changed due to muscular activity and blood condensed due to perspiration . The physical load levels of baseball players were influenced more by extreme heat than by exercise during the game . 2) The group of starting players showed higher body weight loss, oral temperature, heart rate, blood condensation and muscle deviation ferment levels than the group of players on the bench due to the difference in the length of exposure to summer heat and the amount of physical exertion . The changes in physical load levels during the game for the group of starting players were greater than those for the group for players on the bench . 3) Considering the changes in body weight, blood condensation and muscle deviation ferment, we can say that physical loads of players differed according to their positions, the pitcher having the greatest load, followed in descending order by the catcher, infielders, and outfielders . It has been recommended that high school baseball players should take different kinds of rest depending on their positions in order to recover from fatigue as soon as possible after a game.

J Antibiot (Tokyo), 1995 Jun, 48(6), 479 - 83
Gentamicin formation in Micromonospora purpurea: stimulatory effect of ammonium; Gonzalez R et al.; The effect of ammonium on the fermentative production of gentamicin in Micromonospora purpurea has been studied using a chemically defined medium . Ammonium chloride concentrations ranging from 20 to 150 mM resulted in a proportional stimulation of growth and antibiotic formation . The use of other ammonium salts exerted a similar effect . Among the products of ammonium assimilation, glutamate and glutamine were able to exert the stimulatory effect . In addition, both amino acids reproduced the stimulation in resting cell systems of this microorganism and this result was not modified by the presence of chloramphenicol, eliminating a possible inductive action as the cause of this effect . The use of a glutamine synthetase inhibitor prevented antibiotic formation . This inhibition was reverted only by glutamine, suggesting that this amino acid was responsible of ammonium stimulation . Glutamine stimulation seems to be due to its ability to produce 2-deoxystreptamine and glucosamine, intermediates of the gentamicin biosynthetic pathway.

J Antibiot (Tokyo), 1995 Jun, 48(6), 439 - 46
Salfredins, new aldose reductase inhibitors produced by Crucibulum sp . RF-3817 . I . Fermentation, isolation and structures of salfredins; Matsumoto K et al.; New inhibitors of aldose reductase, designated salfredins A3, A4, A7, C1, C2, C3 and B11, were isolated from the fermentation broth of Crucibulum sp . RF-3817 by successive purification procedures of solvent extraction, silica gel column chromatographies and reverse-phase HPLC . Their structures were established by spectroscopic methods, including UV, SI-MS and NMR . The structures of salfredins A4 and B11 were confirmed by X-ray crystallographic analysis.

Biosci Biotechnol Biochem, 1995 Jun, 59(6), 1147 - 9
Angiotensin I converting enzyme inhibitory activities of various fermented foods; Okamoto A et al.; Angiotensin I converting enzyme (ACE, E.C . 3.4.15.1) inhibitory activity were measured with 11 kinds (31 items) of fermented foods . Strong inhibitory activity was detected in soy sauce, fish sauce, natto, nyufu, and cheese, but not in mirin, sake, or vinegar.

Biosci Biotechnol Biochem, 1995 Jun, 59(6), 1126 - 7
Koninginin C: a biologically active natural product from Trichoderma koningii; Parker SR et al.; Koninginin C, a congener of koninginins A and B, was isolated from Trichoderma koningii fermented on a shredded wheat medium . The compound inhibited the growth of etiolated wheat coleoptiles by 100% at 10(-3) M . It was a fine, white crystalline substance with a molecular formula of C16H28O4 and a melting point of 70-72 degrees C.

Eur J Biochem, 1995 Jun 1, 230(2), 773 - 8
High-level production, chemical modification and site-directed mutagenesis of a cephalosporin C acylase from Pseudomonas strain N176; Ishii Y et al.; A cephalosporin acylase from Pseudomonas strain N176 hydrolyses both 7-beta-(4-carboxybutanamido)-cephalosporanic acid (glutarylcephalosporanic acid) and cephalosporin C to 7-amino-cephalosporanic acid . However, its productivity in the original host was low and its activity against cephalosporin C was not sufficient for direct large-scale production of 7-amino-cephalosporanic acid . In order to overcome these problems, we established a high-level expression system for the acylase in Escherichia coli . Tyr270 in the acylase is reported to play an important role in the interaction with glutarylcephalosporanic acid, as determined from the reaction with an affinity-label reagent, 7 beta-(6-bromohexanoylamido) cephalosporanic acid {Ishii, Y., Saito, Y., Sasaki, H., Uchiyama, F., Hayashi, M., Nakamura, S . & Niwa, M . (1994) J . Ferment . Bioeng . 77, 598-603} and modification with tetranitromethane {Nobbs, T . J., Ishii, Y., Fujimura, T., Saito, Y . & Niwa, M . (1994) J . Ferment . Bioeng . 77, 604-609} . From carbamoylation with potassium cyanate and site-directed point mutagenesis of the cephalosporin C acylase, we have deduced that Tyr270 exists at a position where it can interact with a residue (possibly Ser239) corresponding to inactivation by carbamoylation . We mutated Met269 and Ala271 of the acylase and found that mutation of Met269 to Tyr or Phe caused a 1.6-fold and 1.7-fold increase, respectively, of specific activity against cephalosporin C as compared to that of the wild-type enzyme . Kinetic studies of these mutants revealed that their kcat values increased, although their Km values against cephalosporin C were not changed . These data indicate that the mutation of Met269 near Tyr270 induces a minor conformational change to increase the stability of the activated complex with the enzyme and cephalosporin C . In particular, a mutant in which Met269 was replaced by Tyr was 2.5-fold more efficient in converting cephalosporin C to 7-amino-cephalosporanic acid than the wild-type enzyme under conditions similar to those in a bio-reactor system.

Eur J Biochem, 1995 Jun 1, 230(2), 698 - 704
Activation of (R)-2-hydroxyglutaryl-CoA dehydratase from Acidaminococcus fermentans; Muller U et al.; (R)-2-Hydroxyglutaryl-CoA dehydratase (HgdAB) from Acidaminococcus fermentans catalyses the reversible dehydration of its substrate to glutaconyl-CoA . The enzyme has to be activated by ATP, MgCl2, and Ti(III)citrate by an activator protein (HgdC) that is present in the organism at very low concentrations . Cell-free extracts of a recombinant Escherichia coli strain, in which hgdC was expressed, contained the activator with a specific activity of up to 45 U'/mg protein (1 U' is the amount of activator required to generate 1 U dehydratase activity under standard assay conditions) . The recombinant protein was purified 44-fold to a specific activity of 2000 U'/mg . It is a homodimer (gamma 2, 54 kDa) and contains 4 mol non-heme iron and 3 mol inorganic sulfur . Under air, the activator has a half-life of seconds and even under strict anaerobic conditions it is very unstable . The amino acid sequence of the activator shows similarities to the ATP-binding motifs of several kinases . The dehydratase component was purified from its natural source revealing a heterodimer (alpha beta, 100 kDa) that contains 4 mol non-heme iron, 4 mol inorganic sulfur, 0.3 mol riboflavin, and 1 mol FMN . A mechanism is proposed in which an iron-sulfur cluster or a flavin donates one electron to the thiolester of the substrate (R)-2-hydroxyglutaryl-CoA . The resulting ketyl may eliminate the adjacent hydroxyl group yielding an enoxy radical from which the beta-hydrogen is abstracted as a proton leading to the ketyl of glutaconyl-CoA . In the final step, the latter is oxidized to the product, whereby the reduced enzyme is regenerated . It is suggested that during the activation step, the electron of this cycle is fed into the enzyme by Ti(III)citrate and energized by hydrolysis of ATP; both functions are apparently catalysed by the activator . The enzyme remains in this activated state for several turnovers, which may explain the requirement of only catalytic amounts of ATP and substoichiometric amounts of activator (dehydratase/activator ratio approximately 200:1) . The oxidants 4-nitrobenzoate, 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone or chloramphenicol (all at concentrations greater than or equal to 1 microM) may trap this electron resulting in a reversible, transient inactivation of the dehydratase.

Microbiol Rev, 1995 Jun, 59(2), 304 - 22
The plasma membrane of Saccharomyces cerevisiae: structure, function, and biogenesis; van der Rest ME et al.; The composition of phospholipids, sphingolipids, and sterols in the plasma membrane has a strong influence on the activity of the proteins associated or embedded in the lipid bilayer . Since most lipid-synthesizing enzymes in Saccharomyces cerevisiae are located in intracellular organelles, an extensive flux of lipids from these organelles to the plasma membrane is required . Although the pathway of protein traffic to the plasma membrane is similar to that of most of the lipids, the bulk flow of lipids is separate from vesicle-mediated protein transport . Recent advances in the analysis of membrane budding and membrane fusion indicate that the mechanisms of protein transport from the endoplasmic reticulum to the Golgi and from the Golgi to plasma membrane are similar . The majority of plasma membrane proteins transport solutes across the membrane . A number of ATP-dependent export systems have been detected that couple the hydrolysis of ATP to transport of molecules out of the cell . The hydrolysis of ATP by the plasma membrane H(+)-ATPase generates a proton motive force which is used to drive secondary transport processes . In S . cerevisiae, many substrates are transported by more than one system . Transport of monosaccharide is catalyzed by uniport systems, while transport of disaccharides, amino acids, and nucleosides is mediated by proton symport systems . Transport activity can be regulated at the level of transcription, e.g., induction and (catabolite) repression, but transport proteins can also be affected posttranslationally by a process termed catabolite inactivation . Catabolite inactivation is triggered by the addition of fermentable sugars, intracellular acidification, stress conditions, and/or nitrogen starvation . Phosphorylation and/or ubiquitination of the transport proteins has been proposed as an initial step in the controlled inactivation and degradation of the target enzyme . The use of artificial membranes, like secretory vesicles and plasma membranes fused with proteoliposomes, as model systems for studies on the mechanism and regulation of transport is evaluated.

J Nutr Sci Vitaminol (Tokyo), 1995 Jun, 41(3), 281 - 91
Effects of fructooligosaccharides on the absorption of iron, calcium and magnesium in iron-deficient anemic rats; Ohta A et al.; We investigated the effects of fructooligosaccharides (FO)-feeding on the absorption of iron (Fe), calcium (Ca) and magnesium (Mg) and on the biochemical parameters in Fe-deficient anemic rats . Fe-deficient anemic rats were made by feeding an Fe-deficient diet for 3 weeks . Then these Fe-deficient rats were fed an experimental diet that contained one of two levels of Fe (15 or 30 mg/kg diet), in the form of ferric pyrophosphate, and one of two levels of FO (0 or 50 g/kg diet) for 2 weeks . After the rats were fed these experimental diets, FO-feeding increased the hematocrit ratio, the concentration of hemoglobin and the hemoglobin regeneration efficiency during the first week . Also, the apparent absorption of Fe was increased by FO-feeding . The levels of Fe in the diet did not affect the absorption of Ca and Mg . However, FO-feeding increased the absorption of Ca and Mg . FO-feeding lowered the pH and raised the solubility of Fe, Ca and Mg in the cecal contents, suggesting that those increasing effects of FO-feeding on absorption of these minerals is correlated with fermentation of FO in the large intestine, namely, the cecum and colon . We concluded that FO-feeding improved recovery from anemia and increased the absorption of Fe, Ca and Mg in Fe-deficient anemic rats.

Biochemistry, 1995 May 30, 34(21), 7161 - 9
A variable-temperature direct electrochemical study of metalloproteins from hyperthermophilic microorganisms involved in hydrogen production from pyruvate; Smith ET et al.; The hyperthermophilic bacterium Thermotoga maritima and the hyperthermophilic archaeon Pyrococcus furiosus grow optimally at 80 and 100 degrees C, respectively, by the fermentation of carbohydrates to organic acids, CO2, and H2 . Pyruvate is a major source of reductant for H2 production during fermentation, and pyruvate ferredoxin oxidoreductase (POR), a 4Fe-type ferredoxin, and hydrogenase have been previously purified from both species . P . furiosus utilizes a copper-iron-containing POR and a nickel-iron-containing hydrogenase, whereas the POR of T . maritima lacks copper and its hydrogenase lacks nickel . For all four enzymes and for the two ferredoxins, we have determined their reduction potentials (E degrees') and, where possible, thermodynamic parameters associated with electron transfer (delta S degrees and delta H degrees), using differential pulse voltammetry at temperatures ranging from 25 to 95 degrees C . At ambient temperature, the E degrees' values for all six proteins were comparable and spanned less than 50 mV, but their temperature dependence varied dramatically, even between analogous proteins, such that in the physiological-relevant temperature range the E degrees' values became widely separated . In most cases, transition points were observed in E degrees'/temperature profiles, and these generally corresponded with significant increases in catalytic activity, but occurred at lower temperatures in T . maritima than in P . furiosus . The two ferredoxins (and also P . furiosus rubredoxin) had much more negative entropy terms than were calculated for POR and hydrogenase, and these values were also more negative than those previously reported for mesophilic redox proteins . The reduction potentials measured at high temperatures and likely efficiencies of electron transfer between the various proteins were consistent with in vitro activity measurements.(ABSTRACT TRUNCATED AT 250 WORDS)

Eur J Biochem, 1995 May 15, 230(1), 133 - 8
GTP hydrolysis by HypB is essential for nickel insertion into hydrogenases of Escherichia coli; Maier T et al.; The product of the hypB gene, which is required for the maturation of the three {NiFe}hydrogenases of Escherichia coli, is a member of the GTPase family and exhibits a low intrinsic GTPase activity . It was studied whether or not GTP hydrolysis by HypB is coupled to nickel insertion into hydrogenases and to maturation of hydrogenases . Mutations were introduced into the hypB gene at sites expected to code for amino acids involved in guanine-nucleotide binding . Lys117 of G-motif 1, as well as Asp241 of G-motif 4 were substituted by asparagine residues . The purified mutant HypB proteins showed strongly reduced, but still significant, GTPase activity . In the case of {D241N}HypB, the kcat/Km value was lowered by a factor of 85 and the specificity of the enzyme for GTP was apparently lost, with other nucleoside triphosphates including XTP becoming compatible substrates . The decrease in GTPase activity was even more pronounced for {K117N}HypB . To assess the functionality of these HypB proteins in vivo, the wild-type hypB gene in the chromosome of E . coli was replaced by the mutant alleles . The resulting mutant strains BKN117 and BDN241 were affected in hydrogen metabolism under fermentative conditions . BKN117 did not display hydrogenase activity due to a loss of nickel incorporation into the large subunit . BDN241 exhibited a reduction of hydrogenase activity by 44% and only a portion of the hydrogenase 3 large subunit was in the mature nickel-containing form . From these results, it is concluded that GTP hydrolysis catalysed by HypB is an integral process in nickel incorporation into hydrogenases.

J Mol Biol, 1995 May 12, 248(4), 804 - 11
Genetic analysis of the folded structure of yeast mitochondrial cytochrome b by selection of intragenic second-site revertants; di Rago JP et al.; The mutations C133-->Y133, L282-->F282 and G340-->E340 in yeast mitochondrial cytochrome b each lead to a dysfunction of the cytochrome bc1 complex and, consequently, to the absence of growth on non-fermentable substrates . We isolated and characterized, from these mutants, fourteen different intragenic pseudo-revertants of various respiratory sufficient phenotypes . Both first-site and second-site suppressor mutations were found . A novel type of suppressor mutation consisted of the three-base-pair deletion of the parental mutated codon (E340 delta) . The results provide, for the first time, evidence for the transmembrane disposition of helices F and G of the current eight-helix cytochrome b model . These two helices are presumably in contact with helix C in the folded protein . A simple modelisation study suggests that the packing of helices C, F and G in cytochrome b may be similar to that of helices I, II and VII in bacteriorhodopsin, respectively . We observed from the study of second-site revertants that compensation across the membrane never occurs . For each revertant, the suppressor mutation and the corresponding target mutation are on the same side of the membrane . This membrane sidedness strengthens the topological constraints imposed by the Q-cycle, namely the necessity of spatial separation of two catalytic reaction sites for ubiquinone.

J Biol Chem, 1995 May 5, 270(18), 10861 - 7
Complementation of Saccharomyces cerevisiae strains containing fatty acid activation gene (FAA) deletions with a mammalian acyl-CoA synthetase; Knoll LJ et al.; Four unlinked fatty acid activation (FAA) genes encoding acyl-CoA synthetases have been identified in Saccharomyces cerevisiae and characterized by noting the phenotypes of isogenic strains containing all possible combinations of faa null alleles . None of these genes is required for vegetative growth when acyl-CoA production by the fatty acid synthetase (Fas) complex is active . When Fas is inhibited by cerulenin, exponentially growing cells are not viable on media containing a fermentable carbon source unless supplemented with fatty acids such as myristate, palmitate, or oleate . The functionally interchangeable FAA1 and FAA4 genes are responsible for activation of these imported fatty acids . Analysis of lysates prepared from isogenic FAA1FAA4 and faa1 delta faa4 delta strains indicated that Faa1p and Faa4p together account for 99% of total cellular myristoyl-CoA and palmitoyl-CoA synthetase activities . Genetic complementation studies revealed that rat liver acyl-CoA synthetase (RLACS) rescues the viability of faa1 delta faa4 delta cells in media containing a fermentable carbon source, myristate or palmitate, plus cerulenin . Rescue is greater at 37 degrees C compared with 24 degrees C, paralleling the temperature-dependent changes in RLACS activity in vitro as well as the enzyme's ability to direct incorporation of tritiated myristate and palmitate into cellular phospholipids in vivo . Complementation by RLACS is blocked by treatment of cells with triacsin C (1-hydroxy-3-(E,E,E,2',4',7'- undecatrienylidine)triazene) . Even though Faa1p, Faa4p, and RLACS are all able to activate imported myristate and palmitate in S . cerevisiae, the sensitivity of Faa4p and RLACS, but not Faa1p, to inhibition by triacsin C suggests that the rat liver enzyme is functionally more analogous to Faa4p than to Faa1p . Finally, an assessment of myristate and palmitate import into FAA1FAA4 and faa1 delta faa4 delta strains, with or without episomes that direct overexpression of Faa1p, Faa4p or RLACS, indicated that fatty acid uptake is not coupled to activation in S . cerevisiae.

J Biol Chem, 1995 May 5, 270(18), 10395 - 404
Cloning and disruption of CKB1, the gene encoding the 38-kDa beta subunit of Saccharomyces cerevisiae casein kinase II (CKII) . Deletion of CKII regulatory subunits elicits a salt-sensitive phenotype; Bidwai AP et al.; Saccharomyces cerevisiae casein kinase II (CKII) contains two distinct catalytic (alpha and alpha') and regulatory (beta and beta') subunits . We report here the isolation and disruption of the gene, CKB1, encoding the 38-kDa beta subunit . The predicted Ckb1 sequence includes the N-terminal autophosphorylation site, internal acidic domain, and potential metal binding motif (CPX3C-X22-CPXC) present in other beta subunits but is unique in that it contains two additional autophosphorylation sites as well as a 30-amino-acid acidic insert . CKB1 is located on the left arm of chromosome VII, approximately 33 kilobases from the centromere and does not correspond to any previously characterized genetic locus . Haploid and diploid strains lacking either or both beta subunit genes are viable, demonstrating that the regulatory subunit of CKII is dispensable in S . cerevisiae . Such strains exhibit wild type behavior with regard to growth on both fermentable and nonfermentable carbon sources, mating, sporulation, spore germination, and resistance to heatshock and nitrogen starvation, but are salt-sensitive . Salt sensitivity is specific for NaCl and LiCl and is not observed with KCl or agents which increase osmotic pressure alone . These data suggest a role for CKII in ion homeostasis in S . cerevisiae.

J Antibiot (Tokyo), 1995 May, 48(5), 380 - 6
Simple aromatics identified with a NFAT-lacZ transcription assay for the detection of immunosuppressants; Burres NS et al.; Determination of the mechanism of action of FK506 and cyclosporin A has yielded new molecular targets involved in signal transduction during T cell activation . A common target of FK506 and cyclosporin A is inhibition of activation of the NFAT transcription factor, for which a specific binding region is present in the promoter of the IL-2 gene . A reporter gene assay has been used to screen for agents that interfere with this early step in T cell activation . Simple aromatic compounds that block NFAT-dependent transcription and show in vitro immunosuppressive activity were isolated from the broth and mycelia of two Streptomyces sp . fermentations . The compounds were active at concentrations that were not directly cytotoxic.

J Antibiot (Tokyo), 1995 May, 48(5), 375 - 9
Isolation, characterization and structure of a new allenic polyine antibiotic produced by fungus LL-07F275; Schlingmann G et al.; Antibiotic 07F275 (1), produced by submerged fermentations of fungal culture LL-07F275, was isolated and characterized despite its inherent instability . Its UV spectrum was identical with that of nemotin, a member of the allenic polyacetylene family, but a molecular weight of 218 daltons indicated a new compound . Structure 1 was determined on the basis of spectroscopic evidence, particularly NMR . Since 1 is a thirteen carbon-containing allenic diyne, it is closely related to mycomycin.

J Antibiot (Tokyo), 1995 May, 48(5), 369 - 74
Phenamide, a fungicidal metabolite from Streptomyces albospinus A19301 . Taxonomy, fermentation, isolation, physico-chemical and biological properties; Makkar NS et al.; A new derivative of phenylalanine, phenamide, was discovered from the fermentation broth of an actinomycete identified as a member of the Streptomyces albospinus cluster . Phenamide was purified using successive C18 reverse phase and cation exchange chromatography . Its structure was determined by spectroscopic and chemical methods . Its molecular formula, C14H20N2O3, was determined by HRFAB-MS . Phenamide showed activity against Septoria nodorum, the causal agent of wheat glume blotch.

J Antibiot (Tokyo), 1995 May, 48(5), 357 - 62
Trachyspic acid, a new metabolite produced by Talaromyces trachyspermus, that inhibits tumor cell heparanase: taxonomy of the producing strain, fermentation, isolation, structural elucidation, and biological activity; Shiozawa H et al.; Trachyspic acid, a new metabolite that inhibited heparanase, was isolated from the culture broth of Talaromyces trachyspermus SANK 12191 . Its structure was deduced from NMR spectral analyses and chemical reactions as a tricarboxylic acid derivative containing a spiroketal . The IC50 value of trachyspic acid against heparanase was 36 microM.

Gut, 1995 May, 36(5), 737 - 42
Constitutive and cytokine induced expression of HLA molecules, secretory component, and intercellular adhesion molecule-1 is modulated by butyrate in the colonic epithelial cell line HT-29; Kvale D et al.; Normal colonic epithelial cells play an important part in the mucosal immune system and use butyrate, a bacterial fermentation product, as an important energy source . Butyrate deficiency has been associated with inflammatory bowel disease, diversion colitis, and pseudomembranous colitis . Butyrate effects on important molecules for epithelial immune functions were studied in a colonic epithelial cell line (HT-29): the constitutive and cytokine regulated expression of secretory component (poly-Ig receptor), HLA class I and II molecules, and intercellular adhesion molecule-1 (ICAM-1) . Butyrate facilitated the constitutive expression of secretory component and HLA class I . Butyrate furthermore tended to enhance cytokine mediated stimulation of protein expression, although tumour necrosis factor alpha (TNF) and interleukin 4 (IL 4) responses on HLA class I and secretory component, respectively, were relatively inhibited by butyrate . Cytokine mediated accumulation in the various mRNAs usually increased even more in the presence of butyrate, with the exception of TNF response on HLA class I and secretory component mRNA concentrations . In conclusion, butyrate may substantially influence constitutive and cytokine mediated expression of molecules with immune functions in a complex and differentiated manner, and butyrate deficiencies, as seen in various clinical conditions, might influence mucosal immune responses.

Vet Med (Praha), 1995 May, 40(5), 129 - 32
{The effect of virginiamycin on rumen fermentation in vitro after adaptation of donors to the inoculum}; Marounek M et al.; Virginiamycin is an antibiotic active against grampositive bacteria in the alimentary tract, which is also suitable for supplementation of diets of growing and finishing ruminants . The aim of this work was to specify the effect of virginiamycin on some parameters of rumen fermentation in vitro with inoculi taken from wethers adapted or non-adapted to the virginiamycin intake . Incubations were performed anaerobically at 39 degrees C in serum bottles closed with Bunsen valves . Virginiamycin was added at 0 or 10 mg/l to the rumen fluid diluted with McDougall buffer . Virginiamycin significantly decreased production and utilization of lactic acid, production of methane and decomposition of casein when rumen fluid was taken from non-adapted wethers . Most of its effects disappeared when rumen fluid was sampled from wethers adapted to the virginiamycin intake (100 mg per head daily for 2 months) . Adaptation of wethers to virginiamycin was further confirmed by analyses of the rumen fluid which was used for inoculation of in vitro cultures . Molar percentages of acetate, propionate, butyrate and valerate were the same before and after the adaptation . Therefore it can be concluded that the effects of virginiamycin on rumen parameters are not stable and its addition to ruminant diets cannot be recommended, with exception of the milk nutrition period . In the last experiment the stability of virginiamycin in the rumen fluid of adapted wethers was investigated.(ABSTRACT TRUNCATED AT 250 WORDS)

Lett Appl Microbiol, 1995 May, 20(5), 308 - 11
Disinfectant tolerance and antibiotic resistance in psychrotrophic gram-negative bacteria isolated from vegetables; Fernandez-Astorga A et al.; A total of 330 strains of psychrotrophic non-fermenting Gram-negative bacteria isolated from vegetables were studied . In spite of the wide range of antibiotic resistance occurring, less than 10% showed resistance patterns which included mezclocillin-ticarcillin-gentamicin or ceftizoxime-norfloxacin . Reductions of > 5 log10 in the numbers of cfu were found when these strains were exposed for 30 min to a quaternary ammonium compound (1% w/v).

Curr Microbiol, 1995 May, 30(5), 255 - 8
Production of beta-glucosidase by Aspergillus terreus; Pushalkar S et al.; The production of beta-glucosidase by Aspergillus terreus was investigated in liquid shake cultures . Enzyme production was maximum on the 7th day of growth (2.18 U/ml) with the initial pH of the medium in the range of 4.0-5.5 . Cellulose (Sigmacell Type 100) at 1.0% (wt/vol) gave maximum beta-glucosidase activity among the various soluble and insoluble carbon sources tested . Potassium nitrate was a suitable nitrogen source for enzyme production . Triton X-100 at 0.15% (vol/vol) increased the enzyme levels of A . terreus . The test fungal strain showed an ability to ferment glucose to ethanol.

Biochem J, 1995 May 1, 307 ( Pt 3), 799 - 805
Characterization of a regulated form of phospholipase D in the yeast Saccharomyces cerevisiae; Ella KM et al.; Phospholipase D (PLD), which is present in bacterial, plant and animal cells, can serve as an important element of signal-transduction pathways . This study examined the potential role of this enzyme in the regulation of Saccharomyces cerevisiae . An assay in vitro using a fluorescent 1-acyl-2-alkyl glycerophosphocholine as substrate was used to assess PLD activity in yeast cell extracts . A neutral PLD activity is present in membranes prepared from both haploid and diploid yeast cells, as evidenced by the production of phosphatidic acid and phosphatidylbutanol in the presence of butanol . Alcohols, in addition to serving as substrates for transphosphatidylation, stimulate PLD activity . Increased PLD activity is detected in membranes when either haploid or diploid cells are incubated in the presence of a non-fermentable carbon source . Membrane PLD activity increases within 10 min after diploid cells are placed in a sporulation-inducing medium lacking nitrogen and containing a non-fermentable carbon source . The increased activity persists for 2-3 h, and then declines to control values . This response occurs in the presence of cycloheximide, an inhibitor of protein synthesis . These data indicate that PLD activity is present in yeast, and that activation of PLD is an early event in sporulation in this organism.

Dis Colon Rectum, 1995 May, 38(5), 488 - 93
Acute pouchitis and deficiencies of fuel; Sagar PM et al.; PURPOSE: Acute pouchitis is a troublesome complication after restorative proctocolectomy . Deficiency of fuel, especially short chain fatty acids (SCFA), produced by anaerobic bacterial fermentation of saccharides, is implicated in ulcerative and diversion colitis . Our hypothesis was that SCFA deficiency occurs in acute pouchitis, and correction of the deficiency is associated with resolution of pouchitis . METHODS: Thirty-two patients were studied, 10 with histologically confirmed acute pouchitis and 22 with healthy pouches . Stool concentrations of SCFA (acetic, propionic, butyric, and valeric acids) were determined by gas-liquid chromatography . Quantitative bacteriologic studies of stool were carried out, and four-quadrant pouch biopsies were assessed by a pathologist who was unaware of the clinical state . Patients with pouchitis were treated for six weeks with metronidazole and given dietary advice to increase their intake of fermentable saccharides . RESULTS: Stool concentrations of SCFA were significantly less in pouchitis patients compared with patients with healthy pouches (340 mumol/g (range, 124-492) vs . 93 (range, 44-136) P < 0.01) . No differences in anaerobic or aerobic counts were seen . Resolution of pouchitis was associated with a significant increase in SCFA, but anaerobic counts fell . CONCLUSION: Deficiency of SCFA is implicated in acute pouchitis.

J Bacteriol, 1995 May, 177(9), 2460 - 8
Organization and growth phase-dependent transcription of methane genes in two regions of the Methanobacterium thermoautotrophicum genome; Nolling J et al.; Two regions of the Methanobacterium thermoautotrophicum genome containing genes that encode enzymes involved in methanogenesis (methane genes) have been cloned and sequenced to determine the extent of methane gene clustering and conservation . One region from the M . thermoautotrophicum strains delta H and Winter, extending approximately 13.5 kb upstream from the adjacent mvhDGAB and mrtBDGA operons that encode the methyl-viologen-reducing hydrogenase (MVH) and the methyl coenzyme M reductase II (MRII), respectively, was sequenced, and 76% sequence identity and very similar gene organizations were demonstrated . Five closely linked open reading frames were located immediately upstream of the mvh operon and were designated flpECBDA . The flpCBD genes encode amino acid sequences that are 31, 47, and 65% identical to the primary sequences of the alpha and beta subunits of formate dehydrogenase and the delta subunit of MVH, respectively . Located immediately upstream of the flp genes was the mth gene, which encodes the H2-dependent methylene-tetrahydromethanopterin dehydrogenase (MTH) . In contrast to this mth-flp-mvh-mrt cluster of methane genes, a separate approximately 5.4-kb genomic fragment cloned from M . thermoautotrophicum delta H contained only one methane gene, the mtd gene, which encodes the 8-hydroxy-5-deazaflavin (H2F420)-dependent methylene-tetrahydromethanopterin dehydrogenase (MTD) . Northern (RNA) blot experiments demonstrated that mth was transcribed only at early growth stages in fermentor-grown cultures of M . thermoautotrophicum delta H, whereas mtd was transcribed at later growth stages and in the stationary phase . Very similar transcription patterns have been observed by T.D . Pihl, S . Sharma, and J . N . Reeve (J . Bacteriol . 176:6384-6391, 1994) for the MRI- and MRII-encoding operons, mrtBDGA and mcrBDCGA, im M . thermoautotrophicum deltaH, suggesting coordinated regulation of methane gene expression . In contrast to the growth phase-dependent transcription of the mth/mrt and mtd/mcr genes, transcription of the mvhDGAB and frhADGB operons, which encode the two (NiFe) hydrogenases in M . thermoautotrophicum deltaH, was found to occur at all growth stages.

J Bacteriol, 1995 May, 177(10), 2781 - 8
Use of reporter genes to identify recessive trans-acting mutations specifically involved in the regulation of Aspergillus nidulans penicillin biosynthesis genes; Brakhage AA et al.; Starting from three amino acid precursors, penicillin biosynthesis is catalyzed by three enzymes which are encoded by the following three genes: acvA (pcbAB), ipnA (pcbC), and aat (penDE) . To identify trans-acting mutations which are specifically involved in the regulation of these secondary metabolism genes, a molecular approach was employed by using an Aspergillus nidulans strain (AXTII9) carrying acvA-uidA and ipnA-lacZ gene fusions integrated in double copies at the chromosomal argB gene . On minimal agar plates supplemented with X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside), colonies of such a strain stained blue, which is indicative of ipnA-lacZ expression . After mutagenesis with UV light, colonies were isolated on agar plates with lactose as the carbon source, which produced only a faint blue color or no color at all . Such mutants (named Prg for penicillin regulation) most likely were defective in trans-acting genes . Control experiments revealed that the mutants studied still carried the correct number of gene fusions . In a fermentation run, mutants Prg-1 and Prg-6 exhibited only 20 to 50% of the ipnA-lacZ expression of the wild-type strain and produced only 20 to 30% of the penicillin produced by the wild-type strain . Western blot (immunoblot) analysis showed that these mutants contained reduced amounts of ipnA gene product, i.e., isopenicillin N synthase . Both mutant Prg-1 and mutant Prg-6 also differed in acvA-uidA expression levels from the wild type . Segregation analysis indicated that for both mutants the Prg phenotype resulted from mutation of a single gene . Two different complementation groups, which were designated prgA1 and prgB1, were identified . However, the specific activity of the aat (penDE) gene product, i.e., acyl coenzyme A:6-aminopenicillanic acid acyltransferase, was essentially the same for the mutants as for the wild-type strain, implying that the last step of the penicillin biosynthetic pathway is not affected by the trans-acting mutations identified.

J Anim Sci, 1995 May, 73(5), 1449 - 58
Kinetics of hydration and functional specific gravity of fibrous feed by-products; Bhatti SA et al.; Five studies were conducted to evaluate the kinetics of digestion, hydration, and functional specific gravity (FSG) of various feed by-products (FBP) in vitro . The water-holding capacity (WHC) of alfalfa and orchardgrass (1.428 and 1.005 g/g of insoluble DM {IDM}, respectively) was higher (P < .05) than the WHC of FBP, which ranged from .175 for distillers grains to .481 g/g of IDM for brewers grains pellets . Rate of hydration was the highest in brewers grains pellets and beet pulp (.215 and .252 min-1, respectively), whereas the lowest hydration rates were observed in orchardgrass, corn cob pellets, and soyhulls (.055 to .066 min-1) . Loss of associated gasses from feed particles fermented in vitro increased (P < .05) their FSG when the contents of incubation tubes were transferred to pycnometers, compared with that when the incubation was carried out directly in the pycnometers (1.17 vs 1.13) to determine their FSG . Gas produced during fermentation delayed the increase in the FSG of all sources of brewers grains and beet pulp, corn gluten feed, distillers grains, orchardgrass, alfalfa, and wheat middlings but not of corn cob pellets, cottonseed hulls, and soyhulls . Averaged across hours of incubation, the FSG of FBP (except beet pulp) was either higher (P < .05) or tended to be higher than that of alfalfa and orchardgrass . Particle size of FBP did not influence FSG during fermentation in vitro . The WHC and FSG of feeds may be helpful in predicting the rate of passage of feeds through the rumen.

Yeast, 1995 May, 11(6), 581 - 5
Identification and initial characterization of the cytosolic protein Ycr77p; Rodriguez-Cousino N et al.; The nucleotide sequence of yeast chromosome III encompassing the previously the previously described open reading frames (ORFs) YCR80w, YCR77c and YCR78c (Oliver et al., 1992) has been updated . In the corrected sequence, these ORFs are replaced by two new ORFs, YCR80w (453 bp) and YCR77c (2391 bp) . In addition, the orientation of Ycr79c is reversed to give ORF Ycr79w, which has an unaltered nt sequence . The predicted translation products do not exhibit significant homology to known proteins . ORF Ycr77p encodes an 88 kDa, cytosolic protein . A fraction of the protein is associated with small membranous structures in a salt-sensitive fashion . Initial characterization revealed that the protein is not essential for yeast viability, growth on non-fermentable carbon sources, mating and sporulation . The chromosome III DNA sequence that was used for the analysis has the Accession Number X59720 in the GenBank/EMBL database.

Br J Nutr, 1995 May, 73(5), 687 - 99
The influence of dietary fibre on body composition, visceral organ weight, digestibility and energy balance in rats housed in different thermal environments; Zhao X et al.; The present study was undertaken to provide detailed information on the effect of dietary fibre (DF) level on body composition, visceral organ weight, nutrient digestibility and on energy and protein metabolism of rats housed in cold (16 degrees), warm (24 degrees) or hot (32 degrees) thermal environments . High- or low-fibre diets (257 v . 56 g DF/kg dry matter (DM)) were studied in a 6-week balance experiment (initial body weight about 100 g) . Heat production was measured using open-air circuit respiration chambers . Pea fibre and pectin were used to adjust the DF level in the high-fibre diet . The ranking order of daily gain of rats kept in different environments was: 24 degrees > 16 degrees > 32 degrees, while the ranking order for carcass protein was: 16 degrees > 24 degrees > 32 degrees . Rats on the high-DF diet had a lower daily gain than those on the low DF diet, and more protein in DM of empty body weight (EBW) and less fat . The relative weights (g/kg EBW) of liver, heart and kidney decreased when increasing the environmental temperature . The relative weight of the heart was highest in rats on the high DF level, while liver and kidney weights were unaffected by DF . Per kg EBW, the stomach, small intestine, caecum and colon and the length of colon were significantly greater in rats consuming the high-fibre diet compared with those on the low-fibre diet . Rats kept at low temperature had a significantly heavier gastrointestinal (GI) tract than those kept at the highest temperature . Digestibility of protein, DM and energy was lowest for rats fed on the high-fibre diet . Heat production (HP) of fed rats as well as fasting HP decreased significantly as environmental temperature increased . HP as a proportion of metabolizable energy (ME) was significantly lower for rats at 24 degrees compared with the other environmental temperatures . The proportion of energy retained as protein was slightly higher in rats fed on the high-fibre than on the low-fibre diet . Based on the results of the present study the authors measured a net energy value of 5.4 kJ/g DF fermented; approximately 50% of the DF came from peas . Possible implications of the present findings are discussed.

J Dairy Sci, 1995 May, 78(5), 1142 - 53
Evaluating effects of fish meal on milk fat yield of dairy cows; Spain JN et al.; Experiment 1 measured the effect of different amounts of dietary fish meal on milk yield and composition . Milk fat percentage and yield were decreased by increased fish meal intake, but this change was not associated with changes in ruminal fermentation patterns . Plasma long-chain n-3 polyunsaturated fatty acids were increased as intake of fish meal increased . Ruminal disappearance of DM, CP, and lipid in fish meal was measured in situ . Seventy percent of lipid disappeared by 8 h . Intraruminal administration of fish oil did not alter ruminal fermentation and only slightly changed fatty acid profiles in duodenal digesta, plasma, or milk . Duodenal infusion increased plasma n-3 fatty acids but did not affect composition of fatty acids in milk . Experiment 2 compared effects of dietary fish meal and fish oil on milk production and composition . Fish meal increased n-3 fatty acids in plasma compared with those of the fish oil treatment . No changes were found in milk yield or composition because of experimental treatments . Cows fed fish meal or fish oil differed significantly in plasma fatty acid profiles but did not differ in ruminal VFA concentrations or milk fat yield.

J Dairy Sci, 1995 May, 78(5), 1122 - 30
Evaluation of diets containing supplemental fat with different sources of carbohydrates for lactating dairy cows; Maiga HA et al.; A study was conducted to evaluate the lactational response of high producing cows to diets supplemented with fat that contained additional ruminally degradable carbohydrate from a molasses plus fat product and dried whey . Forty Holstein cows were randomly assigned within lactation group to receive diets containing 2% tallow with or without molasses or dried whey wk 4 through 16 postpartum . Cows were fed 1) the control TMR of 25% corn silage, 25% alfalfa hay, and 50% concentrate mix, 2) the TMR containing fat, 3) the TMR containing molasses and fat, or 4) the TMR containing dried whey and fat . Production of milk and 3.5% FCM was increased by supplemental fat . Milk protein and fat percentages were not affected by supplemental fat with or without molasses or dried whey . The DMI and BW were similar for all diets . Production efficiency (3.5% FCM/DMI) was higher for cows fed supplemental fat diets, and cows fed tallow alone were more efficient than those fed tallow with molasses or dried whey . Tallow did not influence ruminal concentrations of various VFA . Molar percentage of butyrate was higher for cows fed the TMR containing molasses plus fat or dried whey plus fat than for cows fed the TMR containing fat . The TMR containing 2% tallow increased milk production, but no economic advantage was derived from inclusion of an additional ruminally fermentable carbohydrate as molasses or from dried whey with fat.

J Dairy Sci, 1995 May, 78(5), 1106 - 15
Influence of roasting or sodium hydroxide treatment of barley on digestion in lactating cows; McNiven MA et al.; Three cannulated, lactating cows were used in a 3 x 3 Latin square design to determine the effect of roasting or NaOH treatment of barley on ruminal fermentation and site and extent of digestion of nutrients . Experimental treatments were rolled barley, roasted (exit temperature, 135 degrees C) and rolled barley, and treated with 4% NaOH and 220 L of H2O/tonne of barley . Diets also consisted of grass silage and soybean meal . Treatment with NaOH reduced concentrations of several AA, starch, and NDF in the barley . Starch digestibility in the rumen was lower for barley that was treated with NaOH but was unaffected for roasted barley . Digestibilities of N and starch in the small intestine were reduced for barley treated with NaOH, but values for rolled and roasted barley were similar . Apparent total tract digestibility of starch was reduced for the NaOH treated barley . Treatment of barley with NaOH tended to have a detrimental effect on feed intake, digestibility, and milk production . Roasting of barley did not appear to affect the site or extent of carbohydrate digestion, but roasting protected N from ruminal degradation . The protective effect on the carbohydrate fraction would be expected to be greater if the grain were cooled prior to rolling so that the protein matrix of the starch granule remained intact.

Int J Food Sci Nutr, 1995 May, 46(2), 125 - 36
Reducing cassava toxicity by heap-fermentation in Uganda; Essers AJ et al.; Processing of cassava roots by the Alur tribe in Uganda includes a stage of solid substrate fermentation in heaps . Changes in cyanogen levels during the process, microflora involved, and protein levels, amino acid patterns and mycotoxin contamination of the final products were studied . Processing was monitored at six rural households and repeated at laboratory site, comparing it to sun-drying . Flour samples from rural households were analysed for residual cyanogens, mutagenicity, cytotoxicity and aflatoxins . Mean (+/- SD) total cyanogen levels in flours collected at rural households were 20.3 (+/- 16.8) mg CN equivalents kg-1 dry weight in 1990 (n = 23) and 65.7 (+/- 56.7) in 1992 (n = 21) . Mean (+/- SD) levels of cyanohydrins plus HCN were 9.1 (+/- 8.7) in the 1992 flours . Total cyanogen levels in the village monitored batches were reduced considerably by heap-fermentation from 436.3 (+/- 140.7) to 20.4 (+/- 14.0) mg CN equivalents kg-1 dry weight cassava . Residual cyanogen levels were positively correlated with particle size of the resulting crumbs . Heap-fermentation was significantly more effective in reducing cyanogen levels than sun-drying alone, but did not always result in innocuous levels of of cyanogens . Dominant mycelial growth was from the fungi Neurospora sitophila, Geotrichum candidum and Rhizopus oryzae . No mutagenicity, cytotoxicity nor aflatoxins could be detected in the flours . Protein quantity and quality were not significantly reduced . Cassava gel viscosity pattern was modified to the consumers' preference by this method . As the removal of cyanogens was more efficient and we found no new obvious health risk, heap-fermentation can be regarded as an improvement compared to sun-drying alone in areas where cassava varieties with higher cyanogen levels prevail, but we recommend optimisation of the process for ensuring still safer products.

Biotechnol Prog, 1995 May-Jun, 11(3), 235 - 50
Biosorption of heavy metals; Volesky B et al.; Only within the past decade has the potential of metal biosorption by biomass materials been well established . For economic reasons, of particular interest are abundant biomass types generated as a waste byproduct of large-scale industrial fermentations or certain metal-binding algae found in large quantities in the sea . These biomass types serve as a basis for newly developed metal biosorption processes foreseen particularly as a very competitive means for the detoxification of metal-bearing industrial effluents . The assessment of the metal-binding capacity of some new biosorbents is discussed . Lead and cadmium, for instance, have been effectively removed from very dilute solutions by the dried biomass of some ubiquitous species of brown marine algae such as Ascophyllum and Sargassum, which accumulate more than 30% of biomass dry weight in the metal . Mycelia of the industrial steroid-transforming fungi Rhizopus and Absidia are excellent biosorbents for lead, cadmium, copper, zinc, and uranium and also bind other heavy metals up to 25% of the biomass dry weight . Biosorption isotherm curves, derived from equilibrium batch sorption experiments, are used in the evaluation of metal uptake by different biosorbents . Further studies are focusing on the assessment of biosorbent performance in dynamic continuous-flow sorption systems . In the course of this work, new methodologies are being developed that are aimed at mathematical modeling of biosorption systems and their effective optimization . Elucidation of mechanisms active in metal biosorption is essential for successful exploitation of the phenomenon and for regeneration of biosorbent materials in multiple reuse cycles . The complex nature of biosorbent materials makes this task particularly challenging . Discussion focuses on the composition of marine algae polysaccharide structures, which seem instrumental in metal uptake and binding . The state of the art in the field of biosorption is reviewed in this article, with many references to recent reviews and key individual contributions.

Appl Microbiol Biotechnol, 1995 May-Jun, 43(2), 206 - 10
Effect of perfluorodecalin as an oxygen carrier on actinorhodin production by Streptomyces coelicolor A3(2); Elibol M et al.; Perfluorodecalin, a perfluorocarbon (PFC), was used in this investigation as a dissolved oxygen carrier in the media of Streptomyces coelicolor cultures . The effects of different concentrations of PFC, PFC emulsified with pluronic F-68 and pluronic alone were investigated in the shake-flask cultures using both defined and complex media . In the defined medium with PFC alone, the maximum biomass and actinorhodin concentrations and the volumetric substrate consumption rates increased with increasing PFC concentration . They decreased dramatically, however, when the PFC concentration exceeded 50% (v/v) . Emulsifying the PFC with pluronic F-68 resulted in a significant increase in antibiotic concentration while growth was unaffected . The inclusion of more than 4 g/l pluronic alone in the fermentation medium inhibited the growth . In the complex medium with 40% (v/v) PFC, although the final antibiotic concentration was unaffected, the onset of actinorhodin accumulation was 2 days earlier than that in the control . It was demonstrated that PFC and emulsified PFC did not have any deleterious effects on S . coelicolor cultures.

J Ind Microbiol, 1995 May, 14(5), 396 - 402
Molecular cloning, expression and evaluation of phosphohydrolases for phytate-degrading activity; Moore E et al.; Four acid phosphatase (phosphomonoesterase E.C.3.1.3.2) genes were cloned by polymerase chain reaction (PCR) . These were pho3, pho5 and pho11 from Saccharomyces cerevisiae and the gene for a phosphate-respressible acid phosphatase from Aspergillus niger . The individual genes were subcloned into an A . oryzae expression vector downstream from a starch-inducible alpha-amylase promoter and the resulting expression constructs were transformed into a mutant strain of A . oryzae, AO7 . Southern hybridization analysis confirmed that the acid phosphatase genes had been integrated into the host genome with estimates of integrated copy numbers ranging from 2 to 20 for individual transformants . Northern hybridization analysis of total RNA from individual transformants revealed the presence of a single transcript of the expected size of 1.8 kb . Production of recombinant protein was induced by the addition of 30 g L-1 of soluble starch in the fermentation media . Active acid phosphatases, not present in control cultures, were detected in the supernatant fractions of transformant cultures by acid phosphatase activity staining of non-denaturing polyacrylamide gels . The ability of the recombinant acid phosphatases to hydrolyze phytate was assessed by referenced phytase (myoinositol hexakisphosphate phosphohydrolase E.C . 3.1.3.8) activity assay procedures . A two- to six-fold increase in phytase activity was measured in transformants compared to control, untransformed A . oryzae . Sufficient quantities of A . niger and pho5 recombinant acid phosphatases were generated from large-scale fermentations to assess the efficacy of these enzymes as phytate-degrading enzymes when included in poultry diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Z Gastroenterol, 1995 May, 33(5), 241 - 6
The application of a semi-continuous colon simulation technique (Cositec) for studying the effects of clindamycin on microbial hindgut metabolism; Stuck K et al.; The semi-continuous colon simulation technique was used as an experimental in vitro model to study potential effects of clindamycin application on basic parameters of microbial hindgut metabolism . Hindgut contents from fistulated pigs kept on conventional diets were used as substrates for incubation . Measurements on reproducibility demonstrated the colon simulation technique as a suitable in vitro method to characterize microbial hindgut metabolism and those factors potentially influencing microbial fermentation . Application of clindamycin resulted in disturbances of microbial steady state metabolism and time- and dose-dependent decreases of SCFA production rates with significant reductions of molar butyrate proportions to almost zero . These effects can be related to the onset of functional disturbances of hindgut function under in vivo conditions since butyrate is an essential trophic factor for colonocytes . In addition, clindamycin induced increases in lactate production with a shift towards D-lactate . The relevance of these changes for hindgut function have to be elucidated in further experiments.

J Dairy Res, 1995 May, 62(2), 331 - 8
Effect of oxygen tension on killing of Escherichia coli by bovine polymorphonuclear neutrophil leucocytes in vitro; Goldberg JJ et al.; A batch fermenter modified to simulate the physical conditions of an inflamed v . uninflamed mammary gland was utilized to evaluate the effect of oxygen tension on killing of Escherichia coli P4 by bovine polymorphonuclear neutrophil leucocytes . Leucocytosis was simulated in vitro 4 h after inoculation with Escherichia coli by adding bovine neutrophils isolated from peripheral blood to the culture medium . Experiments were conducted at 39 degrees C in UHT treated milk . At micro-aerophilic oxygen tension (oxygen partial pressure, 3.11 kPa), bacterial numbers declined during the first hour following addition of the neutrophils . Oxygen tension declined rapidly following PMN addition . Once oxygen was depleted, neutrophil activity was presumably diminished and Esch . coli numbers began to increase . Under anaerobic conditions (oxygen partial pressure, 0.17 kPa), no reduction in population was observed . Photomicrographs taken at the time of neutrophil addition and at subsequent time intervals demonstrated a specific association between neutrophils and the pathogen . Subsequent lysis of neutrophils associated with Esch . coli growth was seen coincident with oxygen depletion.

Hum Gene Ther, 1995 May, 6(5), 565 - 73
Cancer gene therapy using plasmid DNA: purification of DNA for human clinical trials; Horn NA et al.; A production method has been developed for the purification of pharmaceutical-grade plasmid DNA for in vivo gene therapy . This method has been applied to the purification of VCL-1005, which is a eukaryotic plasmid expression vector that codes for the production of the HLA-B7 protein . Purified VCL-1005 is formulated with a cationic lipid and injected directly into established tumors of HLA-B7-negative patients with advanced cancers to heighten the patient's immune response against the cancer . The purification of pharmaceutical-grade plasmid DNA requires the development of highly reproducible and scaleable processing methods that meet regulatory standards similar to those required for the manufacture of recombinant protein pharmaceuticals . Defined pharmaceutical standards of purity, potency, efficacy, and safety are routinely met by the process described in this study . The scaleable purification method described here is a combination of highly reproducible unit operations; alkaline lysis, precipitation, and size-exclusion chromatography . The advantages over existing DNA purification methods include improved plasmid purity and the elimination of undesirable process additives such as toxic organic extractants and animal-derived enzymes . The overall process yield of purified plasmid DNA from fermentation through final column purified product is greater than 50% . Contaminating Escherichia coli DNA levels are reproducibly below 1% as measured by Southern analysis . Endotoxin levels are less than 0.03 endotoxin units/micrograms plasmid DNA and residual protein is undetectable . This process was used to produce 100 mg of VCL-1005 for use in an active clinical protocol.

Curr Genet, 1995 May, 27(6), 509 - 16
Purification and binding properties of the Mal63p activator of Saccharomyces cerevisiae; Sirenko OI et al.; Mal63p is a transcriptional activator for maltose fermentation in Saccharomyces cerevisiae . We have purified it to homogeneity from a yeast strain in which the MAL63 gene is under the control of the GAL1-GAL10 promoter . Purification included fractionation of a whole-cell extract by ion-exchange chromatography, chromatography using both non-specific DNA-affinity (calf thymus), and sequence-specific DNA-affinity chromatography . Mal63p activity was assayed by its binding to a fragment of the MAL61-MAL62 promoter, using both filter-binding and electrophoretic-mobility shift assays . DNase-I footprinting identified a new binding site (site 3) between the two previously known sites (sites 1 and 2) . Mal63p is a dimer, and methylation-protection experiments identify the recognition motif as: c/a GC N9 c/a GC/g.

Curr Genet, 1995 May, 27(6), 501 - 8
Molecular analysis of the yeast SER1 gene encoding 3-phosphoserine aminotransferase: regulation by general control and serine repression; Melcher K et al.; Although serine and glycine are ubiquitous amino acids the genetic and biochemical regulation of their synthesis has not been studied in detail . The SER1 gene encodes 3-phosphoserine aminotransferase which catalyzes the formation of phosphoserine from 3-phosphohydroxy-pyruvate, which is obtained by oxidation of 3-phosphoglycerate, an intermediate of glycolysis . Saccharomyces cerevisiae cells provided with fermentable carbon sources mainly use this pathway (glycolytic pathway) to synthesize serine and glycine . We report the isolation of the SER1 gene by complementation and the disruption of the chromosomal locus . Sequence analysis revealed an open reading frame encoding a protein with a predicted molecular weight of 43,401 Da . A previously described mammalian progesterone-induced protein shares 47% similarity with SER1 over the entire protein, indicating a common function for both proteins . We demonstrate that SER1 transcription is regulated by the general control of amino-acid biosynthesis mediated by GCN4 . Additionally, DNaseI protection experiments proved the binding of GCN4 protein to the SER1 promoter in vitro and three GCN4 recognition elements (GCREs) were identified . Furthermore, there is evidence for an additional regulation by serine end product repression.

J Gastroenterol Hepatol, 1995 May-Jun, 10(3), 324 - 30
Dietary modulation of colonic mucosal urokinase activity in rats; Gibson P et al.; The amount and type of dietary fibre ingested influences colonic luminal characteristics, especially the concentration of carbohydrate fermentation products such as butyrate . This study aimed to assess whether diets supplemented with fibres of differing fermentability (delivering different amounts of butyrate to the colon) influence mucosal activities of urokinase and brush border hydrolases, and epithelial turnover . Groups of five rats were fed one of four diets containing low (2%), highly fermented (guar 10% or oat bran 10%) or slowly fermented fibre (wheat bran 10%) for 4 weeks . Activities of urokinase, alkaline phosphatase, dipeptidyl peptidase IV and maltase were measured in mucosal homogenates of proximal and distal colon and from rectum . Proliferative kinetics were assessed in distal and proximal colon by the metaphase arrest technique . Hydrolase activities were similar across all four dietary groups but a significant difference was found for urokinase (P = 0.014) . This was due to a reduction in urokinase activities of > 30% at the three sites in the wheat bran group compared with the other groups . Of proliferative indices, only crypt column height differed across the groups (P = 0.038) and was highest in rats fed wheat bran and lowest in those fed the low fibre diet (P = 0.047) . The proportion of mitoses in the top one-fifth of the crypt also differed across groups (P = 0.038) due to the high values in the distal colon of the low fibre group . Thus, addition of a slowly fermented (but not highly fermented) fibre to the diet of rats reduces net urokinase activity in large bowel mucosa and increases the life span of colonic epithelial cells without changing activities of brush border hydrolases.

J Appl Bacteriol, 1995 May, 78(5), 543 - 7
Expression of novobiocin resistance genes in the novobiocin-producing organism Streptomyces niveus; Hoggarth JH et al.; RNA isolated at intervals during fermentation from the novobiocin-producing wild-type strain of Streptomyces niveus and from a series of novobiocin-non-producing (Nov-) mutants was hybridized to DNA probes containing sequences which specify novobiocin resistance . The probes were made from inserts contained in the clones pGL101 and pGL103 which increase the level of novobiocin resistance of S . lividans transformants from 10 micrograms ml-1 to 50 micrograms ml-1 and 150 micrograms ml-1, respectively . No hybridization was detected with the pGL101 probe . The pGL103 probe hybridized to RNA extracted during the later stages of growth--a pattern corresponding to the transition from low to high level novobiocin resistance during growth of S . niveus wild-type cultures . Neither probe hybridized to RNA extracted from four Nov- mutants . These mutants showed variable levels of novobiocin resistance but none expressed the high wild-type levels . The authors conclude that expression of the DNA sequence in pGL103 is associated with high level novobiocin resistance.

J Biol Chem, 1995 Apr 28, 270(17), 9961 - 70
QSR1, an essential yeast gene with a genetic relationship to a subunit of the mitochondrial cytochrome bc1 complex, is homologous to a gene implicated in eukaryotic cell differentiation; Tron T et al.; Subunit 6 of the mitochondrial cytochrome bc1 complex regulates the activity of the bc1 complex in Saccharomyces cerevisiae but is not essential for respiration . To test whether QCR6, the nuclear gene which encodes subunit 6, might be functionally redundant with any other gene(s), we screened for mutations in yeast genes which are essential when the otherwise non-essential QCR6 is deleted from the yeast chromosome . We obtained such quinolcytochrome c reductase subunit-requiring mutants in two complementation groups, which we named qsr1 and qsr2 . The qsr mutants require QCR6 for viability on fermentable and non-fermentable carbon sources, indicating that QCR6 is covering lethal mutations in qsr1 and qsr2, even when the yeast do not require respiration . QSR1 was cloned by rescuing the synthetic lethality of a qsr1-1 mutant . QSR1 encodes a 25.4-kDa protein which is 65% identical to a protein encoded by QM, a highly conserved human gene which has been implicated in tumorigenesis . In mammals QM is down-regulated during adipocyte, kidney, and heart differentiation, and in Nicotiana the homolog of QM is also down-regulated during differentiation . When one chromosomal copy of QSR1 was deleted in a diploid yeast strain, haploid spores derived therefrom and carrying the deletion were unable to grow on fermentable or non-fermentable carbon sources . Although QCR6 allows the qsr1-1 mutant to grow, it will not substitute for QSR1, since the deletion of QSR1 is lethal even if QCR6 is present . These results indicate a novel genetic relationship between a subunit of the mitochondrial respiratory chain and an essential gene in yeast which is homologous to a gene implicated in differentiation in other eukaryotes.

J Chromatogr A, 1995 Apr 21, 697(1-2), 115 - 22
High-performance liquid chromatography comparison of supercritical-fluid extraction and solvent extraction of microbial fermentation products; Cocks S et al.; The use of supercritical fluids for the extraction of biologically active compounds from the biomass of microbial fermentations has been compared with extraction using the organic solvents methanol and dichloromethane . Compounds representing a range of structural types were selected for investigation . All the extracts obtained were examined using reversed-phase high-performance liquid chromatography . The extractability of metabolites using unmodified and methanol-modified supercritical-fluid carbon dioxide was examined in particular detail for six microbial metabolites: chaetoglobosin A, mycolutein, luteoreticulin, 7,8-dihydro-7,8-epoxy-1-hydroxy-3-hydroxymethyl-xanthone-8-carboxyl ic acid methyl ester, sydowinin B and elaiophylin . The extraction strength of supercritical-fluid carbon dioxide alone appeared to be lower than that of dichloromethane . All the components of interest that were extractable with dichloromethane and methanol were also extractable with methanol-modified carbon dioxide.

Neuroreport, 1995 Apr 19, 6(6), 910 - 2
Mycoplasma fermentans activates the hypothalamo-pituitary adrenal axis in the rat; Weidenfeld J et al.; Intracerebroventricular administration in rats of heat inactivated Mycoplasma fermentans caused a dose- and time-dependent increase in serum adrenocorticotrophin (ACTH) and corticosterone (CS) . In rats with complete deafferentation of the mediobasal hypothalamus, which markedly depleted the median eminence CRF-41, the ACTH and CS responses to M . fermentans were completely inhibited . Pretreatment with dexamethasone abolished the adrenocortical response to M . fermentans . In lipopolysaccharide (LPS) unresponsive C3H/HeJ mice LPS failed to induce the adrenocortical response while administration of M . fermentans elicited a normal CS response . These results suggest that: M . fermentans can activate the hypothalamo-pituitary-adrenal axis via a central mechanism which involves hypothalamic ACTH secretagogue(s), and this effect is sensitive to the negative feedback of glucocorticoids . It is possible that the elevated glucocorticoid levels resulting from mycoplasma infection may be involved in the pathogenesis of mycoplasma-associated diseases.

Yeast, 1995 Apr 15, 11(4), 317 - 25
Transient responses of Candida utilis to oxygen limitation: regulation of the Kluyver effect for maltose; Kaliterna J et al.; The facultatively fermentative yeast Candida utilis exhibits the Kluyver effect for maltose: this disaccharide is respired and assimilated but, in contrast to glucose, it cannot be fermented . To study the mechanism of the Kluyver effect, metabolic responses of C . utilis to a transition from aerobic, sugar-limited growth to oxygen-limited conditions were studied in chemostat cultures . Unexpectedly, the initial response of maltose-grown cultures to oxygen limitation was very similar to that of glucose-grown cultures . In both cases, alcoholic fermentation occurred after a lag phase of 1 h, during which glycerol, pyruvate and D-lactate were the main fermentation products . After ca . 10 h the behaviour of the maltose- and glucose-grown cultures diverged: ethanol disappeared from the maltose-grown cultures, whereas fermentation continued in steady-state, oxygen-limited cultures grown on glucose . The disappearance of alcoholic fermentation in oxygen-limited chemostat cultures growing on maltose was not due to a repression of the synthesis of pyruvate decarboxylase and alcohol dehydrogenase . The results demonstrate that the Kluyver effect for maltose in C . utilis does not reflect an intrinsic inability of this yeast to ferment maltose, but is caused by a regulatory phenomenon that affects a key enzyme in maltose metabolism, probably the maltose carrier . The observed kinetics indicate that this regulation occurs at the level of enzyme synthesis rather than via modification of existing enzyme activity.

FEMS Microbiol Lett, 1995 Apr 15, 128(1), 63 - 8
Mycoplasmas regulate HIV-LTR-dependent gene expression; Nir-Paz R et al.; Mycoplasmas have been incriminated in setting the stage for HIV infection and full-blown AIDS . We tested the possible involvement of mycoplasmas in activation of HIV . Two cell lines, 293 fibroblasts and Jurkat CD4+ T-cells, transfected with plasmids harboring a transcription fusion construct between HIV-long terminal repeat (HIV-LTR) and either luc or cat genes, were infected with several mycoplasmas (M . fermentans; M . penetrans, M . pirum and Ureaplasma urealyticum) and the reporter gene expression was monitored . The data presented here suggest that mycoplasmas, and specifically their membranes, play a role in the activation of HIV-LTR mediated transcription.

J Biol Chem, 1995 Apr 14, 270(15), 8389 - 92
Glyceraldehyde-3-phosphate ferredoxin oxidoreductase, a novel tungsten-containing enzyme with a potential glycolytic role in the hyperthermophilic archaeon Pyrococcus furiosus; Mukund S et al.; The archaeon Pyrococcus furiosus grows optimally at 100 degrees C by the fermentation of carbohydrates to yield acetate, CO2, and H2 . Cell-free extracts contain very low activity of the glycolytic enzyme, glyceraldehyde-3-phosphate dehydrogenase, but extremely high activity of glyceraldehyde-3-phosphate ferredoxin oxidoreductase (GAPOR) . GAPOR was purified under strictly anaerobic conditions . It is a monomeric, O2-sensitive protein of M(r) approximately 63,000 which contains pterin and approximately 1 tungsten and 6 iron atoms per molecule . The enzyme oxidized glyceraldehyde-3-phosphate (Km 28 microM) to 3-phosphoglycerate and reduced P . furiosus ferredoxin (Km 6 microM), but it did not oxidize formaldehyde, acetaldehyde, glyceraldehyde, benzaldehyde, glucose, glucose 6-phosphate, or glyoxylate, nor did it use NAD(P) as an electron acceptor . It is proposed that GAPOR has a glycolytic role and functions in place of glyceraldehyde-3-phosphate dehydrogenase and possibly phosphoglycerate kinase.

Proc Natl Acad Sci U S A, 1995 Apr 11, 92(8), 3358 - 61
Immunogenicity of transgenic plant-derived hepatitis B surface antigen; Thanavala Y et al.; The focus of the Children's Vaccine Initiative is to encourage the discovery of technology that will make vaccines more readily available to developing countries . Our strategy has been to genetically engineer plants so that they can be used as inexpensive alternatives to fermentation systems for production of subunit antigens . In this paper we report on the immunological response elicited in vivo by using recombinant hepatitis B surface antigen (rHBsAg) purified from transgenic tobacco leaves . The anti-hepatitis B response to the tobacco-derived rHBsAg was qualitatively similar to that obtained by immunizing mice with yeast-derived rHBsAg (commercial vaccine) . Additionally, T cells obtained from mice primed with the tobacco-derived rHBsAg could be stimulated in vitro by the tobacco-derived rHBsAg, yeast-derived rHBsAg, and by a synthetic peptide that represents part of the a determinant located in the S region (139-147) of HBsAg . Further support for the integrity of the T-cell epitope of the tobacco-derived rHBsAg was obtained by testing the ability of the primed T cells to proliferate in vitro after stimulation with a monoclonal anti-idiotype and an anti-idiotype-derived peptide, both of which mimic the group-specific a determinant of HBsAg . In total, we have conclusively demonstrated that both B- and T-cell epitopes of HBsAg are preserved when the antigen is expressed in a transgenic plant.

Biochemistry, 1995 Apr 11, 34(14), 4757 - 64
Characterization of human and rat intestinal trefoil factor produced in yeast; Thim L et al.; Intestinal trefoil factor (ITF) from human (hITF) and rat (rITF) have been produced in Saccharomyces cerevisiae . The DNA encoding the two peptides were cloned by polymerase chain reactions (PCR) from a human normal colon library and a rat small intestinal epithelial cell library . Recombinant plasmids were constructed to encode a fusion protein consisting of a hybrid leader sequence and the rat and human ITF sequences, respectively . The leader sequence used serves to direct the fusion protein into the secretory (and processing) pathway of the cell . The secreted recombinant hITF was found in a monomer and a dimer form, whereas the rITF was only secreted as a dimer . The secreted peptides were purified by a combination of ionic exchange chromatography and preparative HPLC . From 8 L of yeast fermentation broth, 256 mg of hITF (monomer) and 133 mg of hITF (dimer) were isolated, and from 8.7 L of fermentation broth, 236 mg of rITF (dimer) was isolated . The structure of hITF (monomer), hITF (dimer), and rITF (dimer) was determined by amino acid analyses, peptide mapping, sequence analyses, and electrospray mass spectrometry analyses . In hITF (monomer) six of the seven cysteines are disulfide-linked to form 3 disulfide bridges . Mass analysis indicated that the last cysteine residue (Cys-57) did not exist as free (-SH) cysteine, but have reacted with cysteine to form an S-S linked cystine . Sequence and mass spectrometry analyses as well as peptide mapping showed that the dimer form of both hITF and rITF is mediated by a disulfide bridge between Cys-57 residues of two monomers.

J Mol Biol, 1995 Apr 7, 247(4), 588 - 96
NCA2, a second nuclear gene required for the control of mitochondrial synthesis of subunits 6 and 8 of ATP synthase in Saccharomyces cerevisiae; Camougrand N et al.; Respiratory-competent nuclear mutants have been isolated which presented a cryosensitive phenotype on a non-fermentable carbon source, due to a dysfunction of the mitochondrial F1-Fo ATP synthase . This defect results from an alteration of the mtDNA-encoded protein synthesis level of subunits 6 and 8 of the Fo sector, due to the simultaneous presence of a mutation in two unlinked nuclear genes . These mutations promote a modification of the expression of the cotranscript ATP8-ATP6 (formerly denoted AAP1-OL12): this mRNA undergoes a maturation at a unique site reaching to two cotranscripts of 5.2 and 4.6 kb in length: in the mutant, the relative amount of 5.2 kb cotranscript was greatly lowered . NCA2 was isolated from a wild-type yeast genomic library by genetic complementation . The relative level of the 5.2 kb transcript, as the synthesis of subunits 6 and 8, was partly restored in the transformed strain . A 1848 nucleotide open reading frame was depicted that encoded an amphiphilic protein of 70,816 Da . Disruption of chromosomal DNA within the reading frame promoted a dramatic decrease of the 5.2 kb mRNA but did not abolish the respiratory competence of a wild-type strain . Hybridization analyses indicated that NCA2 is located on chromosome XVI and produces a single 2750 base transcript.

Biochem Biophys Res Commun, 1995 Apr 6, 209(1), 242 - 9
GLY113-->ASP can restore activity to the ASP51-->SER mutant in the melibiose carrier of Escherichia coli; Wilson DM et al.; ASP51 in the putative membrane-spanning helix 2 of the melibiose carrier of Escherichia coli was replaced by SER . This mutation caused failure of the cell to transport melibiose and failure to ferment melibiose on indicator plates . A melibiose-positive revertant was isolated from these plates and was found to have two additional mutations, GLY113-->ASP (in helix 4) and PHE16-->LEU (in helix 1) . The double mutant ASP51-->SER/GLY113-->ASP was constructed and showed accumulation of melibiose . On the other hand ASP51-->SER/PHE16-->LEU showed no activity . It is concluded that the new carboxyl group at position 113 compensates for the loss of the carboxyl group at position 51.

EMBO J, 1995 Apr 3, 14(7), 1360 - 71
Fps1, a yeast member of the MIP family of channel proteins, is a facilitator for glycerol uptake and efflux and is inactive under osmotic stress; Luyten K et al.; The Saccharomyces cerevisiae FPS1 gene, which encodes a channel protein belonging to the MIP family, has been isolated previously as a multicopy suppressor of the growth defect of the fdp1 mutant (allelic to GGS1/TPS1) on fermentable sugars . Here we show that overexpression of FPS1 enhances glycerol production . Enhanced glycerol production caused by overexpression of GPD1 encoding glycerol-3-phosphate dehydrogenase also suppressed the growth defect of ggs1/tps1 delta mutants, suggesting a novel role for glycerol production in the control of glycolysis . The suppression of ggs1/tps1 delta mutants by GPD1 depends on the presence of Fps1 . Mutants lacking Fps1 accumulate a greater part of the glycerol intracellularly, indicating that Fps1 is involved in glycerol efflux . Glycerol-uptake experiments showed that the permeability of the yeast plasma membrane for glycerol consists of an Fps1-independent component probably due to simple diffusion and of an Fps1-dependent component representing facilitated diffusion . The Escherichia coli glycerol facilitator expressed in a yeast fps1 delta mutant can restore the characteristics of glycerol uptake, production and distribution fully, but restores only partially growth of a ggs1/tps1 delta fps1 delta double mutant on glucose . Fps1 appears to be closed under hyperosmotic stress when survival depends on intracellular accumulation of glycerol and apparently opens rapidly when osmostress is lifted . The osmostress-induced High Osmolarity Glycerol (HOG) response pathway is not required for inactivation of Fps1 . We conclude that Fps1 is a regulated yeast glycerol facilitator controlling glycerol production and cytosolic concentration, and might have additional functions.

Can J Microbiol, 1995 Apr-May, 41(4-5), 424 - 7
An unusual rRNA gene organization in Mycoplasma fermentans (incognitus strain); Huang Y et al.; The macro-restriction map of Mycoplasma fermentans (incognitus strain) was constructed and its rRNA genes were located on the map . It was found that this organism contains two sets of rRNA genes . The 16S and 23S rRNA genes were closely linked as two clusters . However, both 5S rRNA genes were separated from the 16S and 23S genes . The two 16S-23S rRNA gene clusters were arranged in an unusual tail to tail orientation.

Can J Microbiol, 1995 Apr-May, 41(4-5), 309 - 15
Physiological control of trophophase-idiophase separation in streptomycete cultures producing secondary metabolites; Liao X et al.; Cultures of Streptomyces coelicolor A3(2) produced actinorhodin in defined media with various carbon and nitrogen sources . Production occurred during biomass accumulation if assimilation of either the carbon or the nitrogen source limited the rate of growth . High growth rates tended to delay product synthesis until after biomass accumulation was complete, but fully biphasic fermentation profiles were achieved only with media supporting very rapid growth . The onset of actinorhodin production then coincided with a decline in the growth rate during transition of carbon-sufficient cultures to stationary phase . In cultures with maltose as a growth-limiting carbon source, depletion of phosphate increased the rate of actinorhodin biosynthesis, but did not alter the timing of its initiation . With defined media, the use of spores rather than vegetative mycelium as inocula reduced the overlap between trophophase and idiophase . The general guidelines for achieving biphasic production of actinorhodin in S . coelicolor A3(2) cultures could be used to obtain trophophase-idiophase separation in cultures of Streptomyces venezuelae producing chloramphenicol . However, the conditions needed to be modified to give optimized biphasic fermentations with individual strains . Under conditions favouring chloramphenicol production in a distinct idiophase, aromatic amine secondary metabolites in the same cultures of S . venezuelae were produced in a pattern that overlapped the trophophase, suggesting that conditions need to be tailored also to meet differences in the regulation of secondary metabolites.

Am J Clin Nutr, 1995 Apr, 61(4 Suppl), 938S - 945S
Gastrointestinal effects of food carbohydrate; Cummings JH et al.; Dietary carbohydrate may be divided into monosaccharides and disaccharides (sugars), oligosaccharides {degree of polymerization (DP) 3-9}, and polysaccharides (DP > 10) . Their physiological properties and health benefits depend on the site, rate, and extent of their digestion or fermentation in the gut . Oligosaccharides are a diverse group of soluble carbohydrates, many of which are not digested by pancreatic enzymes . They are fermented in the colon and some have specific effects on bacteria . The major dietary polysaccharides are starch and nonstarch polysaccharides (NSPs) . The digestion of starch depends on its physical form, the nature of the starch granule, and the effects of food processing . Starch may be rapidly digested, slowly digested, or resistant, the last passes into the colon for fermentation . The NSPs (cell wall polysaccharides) all resist digestion . They exert a physical effect in the upper gut, serving to moderate carbohydrate and possibly lipid absorption, whereas in the colon they affect bowel habit through fermentation, they affect epithelial cell metabolism, and, along with other fermented carbohydrates, they provide energy to humans.

Eur J Clin Nutr, 1995 Apr, 49(4), 274 - 81
Effects of low-fat milk and fermented low-fat milk on cholesterol absorption and excretion in ileostomy subjects; Andersson H et al.; OBJECTIVE: To study small bowel cholesterol absorption and sterol excretion in order to explain possible serum cholesterol-lowering mechanisms of low-fat milk products . DESIGN: Two 24-h sterol balance studies with 1 litre of low-fat milk or one litre of fermented milk, in random order, added to a controlled diet . {3H}Cholesterol absorption was measured during each period . The results were compared to those on two 24-h periods with isocaloric amounts of lemonade given to the same basic diet, before and after the study . One litre of the two milk products was also consumed in addition to their normal diets in a cross-over design of 3 weeks and with run-in and run-out periods of 2 weeks each with 1000 ml of lemonade preceding the balance studies: SETTING: Outpatient clinic, where the subjects were eating their meals during the day and ileostomy bags collected . SUBJECTS: Nine ileostomy subjects, who have earlier participated in similar studies, volunteered for the study . All subjects completed the study . RESULTS: Cholesterol absorption was highest (66%) in the lemonade period, intermediate in the low-fat milk period (61%) and lowest in the fermented low-fat period (55%) (P < 0.05 for differences) . Net cholesterol excretion (excretion minus intake) and calculated endogenous cholesterol excretion were significantly (P < 0.05 for differences) higher in the low-fat milk period than in the lemonade period and the fermented low-fat milk period . No significant change in serum cholesterol was, however, seen after 3 weeks on each milk regimen . CONCLUSION: Assimilation of cholesterol by microorganisms could possibly explain the reduced uptake of cholesterol with fermented milk . The mechanism behind the increased endogenous cholesterol excretion, induced by low-fat milk, is unclear.

Br J Nutr, 1995 Apr, 73(4), 491 - 505
The role of the large intestine in post-ruminal digestion of feeds as measured by the mobile-bag method in cattle; Vanhatalo A et al.; To study the importance of site of recovery and other factors related to mobile-bag (MB) digestion values, two consecutive experiments in which diets were applied in a 3 x 3 Latin square design, were carried out with cannulated growing heifers . In Expt 1, several types of experimental feed were exposed to intestinal digestion in mobile bags made of two cloth types and filled with intact or rumen-undegradable (RUD) feed material to be recovered either from the ileum (IB) or faeces (FB) . In Expt 2, mean retention time (MRT) of Yb-labelled digesta particles within the intestine and in vivo digestibility of diets were measured . With vegetable concentrates, FB resulted generally in slight overestimation of small-intestinal dry matter and N digestion, while with meat-and-bone meal no difference between FB and IB was found . The respective N digestibility of RUD late-cut silage was clearly underestimated as measured from FB . The disappearance of neutral-detergent fibre (NDF) of all feeds under test was higher from FB than from IB . It was not possible to isolate the influence of the large intestine on the MB values by changing bag cloth type . Irrespective of the longer retention time of bags and longer MRT of Yb in the intestine on a low as compared with a high level of feeding, only NDF disappearance of feeds increased due to lower feeding level . Altering the diet type to increase large-intestinal fermentation, as indicated in vivo, usually had no effect on the MB values . It is concluded that the site of collection of bags does not practically affect small-intestinal digestion values of feed N, unless the feed is rich in fibre.

Pharmazie, 1995 Apr, 50(4), 284 - 92
{One hundred years of biotechnology in the chemical industry in the example of E . Merck, Darmstadt}; Metz H; The purposeful use of microorganisms as producers of pure substances began about one hundred years ago with the production of lactic acid, followed by citric acid and by sorbose for the synthesis of vitamin C . The growth of pure cultures of microorganisms in a technical scale became available nearly fifty years ago by the development of the fermenter . By this it became possible to produce penicillin and other antibiotics, to transform substances in steroid syntheses and to get many enzymes, alkaloids, and other substances from microorganisms . The development of some of the older processes as basis of actual use of biotechnology at E . Merck is described, followed by some facts of the early situation in Germany and some remarks on the inclusions of biotechnology within the chemical industry.

Clin Sci (Lond), 1995 Apr, 88(4), 491 - 9
n-Butyrate mediation of ganglioside expression of human and murine cancer cells demonstrates relative cell specificity; Berenson CS et al.; 1 . n-Butyrate, a short chain fatty acid produced by colonic fermentation, induces differentiation in human neoplastic cell lines, and reduces expression in vitro of a sialyltransferase that glycosylates N-linked glycoproteins in hepatoblastoma cells . Gangliosides are amphipathic, sialylated glycosphingolipids that undergo profound changes in many transformed cells and may protect neoplastic cells from host immune surveillance . Colonic mucosal cells are exposed to luminal short-chain fatty acid concentrations of up to 80 mmol/l, and there is some evidence that short-chain fatty acids may alter ganglioside expression in colon cancer cells . 2 . Because of the importance of gangliosides in cancer pathogenesis, we investigated the effects of n-butyrate on ganglioside expression of colonic (human and murine) and non-colonic cancer cells . 3 . Three separate colon cancer cell lines (LS174T, T84 and MCA-38), when butyrate treated, demonstrated striking amplification of specific individual gangliosides . However, the total lipid-bound sialic acid content of gangliosides of butyrate-treated LS174T cells diminished . In contrast to earlier reports, n-butyrate did not mediate expression of all gangliosides and specifically did not mediate expression of GM3 . This effect persisted even after removal of butyrate . 4 . In contrast, exposure of extracolonic cells to butyrate, including cervical cancer (HeLa) and laryngeal cancer (HEp-2) cell lines in this study and hepatoblastoma cells (Hep G2) in our previous work, caused no detectable changes in ganglioside expression . 5 . In conclusion, our results indicate a relative tissue specificity of butyrate-mediated alterations in ganglioside expression that is not universal but is limited to specific gangliosides.

Int J Biochem Cell Biol, 1995 Apr, 27(4), 403 - 13
Effect of dietary fiber at weaning on protein glycosylation in the rat small intestine; Tardy F et al.; Changes in protein glycosylation which can be modulated by dietary factors are observed in the rat intestinal mucosa at the weaning period . Experiments were performed to evaluate the involvement of dietary fibers in the regulation of such modifications . Groups of rats were abruptly weaned at 19 days of age on semi-synthetic diets differing in dietary fiber content (fiber-free, 10% pectin or 10% cellulose) given for 4 and 10 days . Glycoprotein sugars, activities of the fucosylation pathway and caecal contents were analyzed . Neutral sugar contents in glycoproteins of the small intestinal mucosa were increased in teh fiber-fed groups as compared to fiber-free group, only after 4 days but not after 10 days of diet . Diet-induced modifications in the glycoprotein fucose content of the small intestinal mucosa are partly explained by the coordinated evolution of different activities involved in the fucosylation pathway (GDP-fucose production and breakdown, fucosyltransferase and fucosyltransferase inhibitor) . Caecal contents of short chain fatty acids were significantly different between the three groups after 4 but not after 10 days of diet . There was no correlation between caecal short chain fatty acid contents and activities involved in the fucosylation pathway . The introduction of dietary fibers at weaning induced marked but transient changes in glycoprotein sugars and the fucosylation pathway . The results demonstrate that fucosylation is regulated in several ways including changes in fucosyltransferase activity but that caecal fermentation of dietary fibers was not directly responsible for the observed changes.

Bioseparation, 1995 Apr, 5(2), 113 - 21
Use of multifactorial analysis to develop aqueous two-phase systems for isolation of non-native IGF-I; Hart RA et al.; A high yield procedure was developed to solubilize and extract IGF-I from recombinant E . coli by adding chaotrope and disulfide reductant to alkaline fermentation broth . To enhance centrifugation performance and recovery yield, a salt/polymer aqueous two-phase extraction procedure was developed whereby soluble non-native IGF-I and biomass solids are enriched in separate liquid phases . To develop this extraction system a multifactorial experimental approach was used to simultaneously map the phase diagram and identify conditions to suitably partition IGF-I and cell remnants . The presence of urea in these systems tended to disrupt two-phase formation and solids sedimentation . This, in turn, constrained the concentrations of phase forming solutes which could be effectively used . Systems containing low levels of salt (less than about 4% w/w) and polymer (less than about 10% w/w) did not form two phases . Systems containing high levels of salt (greater than about 7% w/w) and polymer (greater than about 18% w/w) formed two phases with floating solids . Intermediate levels of salt (between about 4% and 7% w/w) and polymer (between about 10% and 18% w/w) formed two phases in which solids were enriched in the heavy phase . Systems in this latter desired category were produced with a variety of different salts and polymers and all enriched non-native IGF-I in the light phase . Highest recovery yield (about 90%) was obtained with systems composed of 5% sodium sulfate and 14% PEG-8000.(ABSTRACT TRUNCATED AT 250 WORDS)

Appl Microbiol Biotechnol, 1995 Apr, 43(1), 42 - 51
Lipase from Pseudomonas fragi CRDA 323: partial purification, characterization and interesterification of butter fat; Pabai F et al.; Several strains of Pseudomonas were screened for lipase production using the rhodamine agar diffusion test . On the basis of the diameter of the halo produced, P . fragi CRDA 323 and P . putida ATCC 795 were considered to be good and weak lipase producers respectively . P . fragi, cultured in a 2-l fermenter, produced a maximal amount of lipase after 3-4 days of incubation at 27 degrees C . The lipase extract of P . fragi was obtained by acidification of culture supernatant at pH 4.0 and partially purified with ammonium sulphate precipitation . The majority of lipase activity (42%) was located in fraction IV, precipitated at 20%-40% of saturation, with a 19-fold enzyme purification . The Km and Vmax values for the partially purified enzymatic extract (fraction IV) were 0.70 mg/ml and 0.97 x 10(-3) U/min respectively . Fraction IV, which showed an optimum activity at pH 8.5, was used for the interesterification of butter fat in a microemulsion free co-surfactant system containing Span 60 (sorbitol monostearate) and Tween 60 (polyoxyethylene sorbitan monostearate) in the ratio 48:52 (v/v) . The results showed that the interesterification of butter fat resulted in a considerable decrease in long-chain saturated fatty acids (C12:0, C14:0 and C16:0) with a concomitant increase in C18:0 and C18:1 at the sn-2 position of selected triacylglycerols . In addition, the results demonstrated an increase in the fatty acids (C12:0, C14:0 and 16:0) among the 1 and 3 positions of the triacylglycerol molecules of modified buffer fat accompanied by a decrease in C18:0 and C18:1.

Appl Microbiol Biotechnol, 1995 Apr, 43(1), 25 - 30
The effect of phosphate concentration on phytase production and the reduction of phytic acid content in canola meal by Aspergillus carbonarius during a solid-state fermentation process; al-Asheh S et al.; The use of canola meal, an abundant side-product of canola oil processing in Canada, as animal feed is hampered by high phytic acid levels that reduce metal cation availability . Aspergillus carbonarius grows well in a solid canola meal medium, produces phytase and reduces the phytic acid content to zero . Inorganic phosphate addition at a concentration of 1 mg and 5 mg/110 g solid-state culture system results in better growth of the microorganism, higher rates and levels of phytase production, and faster reduction of phytic acid content . Phosphate concentrations of 50 mg and 100 mg/110 g inoculated system had a negative effect affecting primarily the initial rates of biomass and phytase production and phytic acid content reduction . Models that predict biomass production (expressed as glucosamine content) and phytase, as well as the reduction of phytic acid content in the solid-state cultures supplemented with phosphate are reported . They fit the experimental results reasonably well (with a maximum deviation of 7%).

Appl Microbiol Biotechnol, 1995 Apr, 43(1), 150 - 5
Development of a continuous system for the degradation of a cyanuric acid by absorbed Pseudomonas sp . NRRL B-12228; Ernst C et al.; Cyanuric acid in high concentrations (15.5 mM) was degraded completely by Pseudomonas sp . NRRL B-12228 independently of glucose concentration . In the batch fermentations there was a relation between the glucose concentration, on the one hand, and the liberation of ammonia or production of protein, on the other . The greater the supply of carbon, the more biomass was produced, and fewer NH4+ ions were released . Continuous fermentations using adsorbed cells could be performed to degrade cyanuric acid . In spite of different glucose feeding there was only a negligible difference in residues of s-triazine . In a one-step continuous system with dilution rates between 0.021 h-1 and 0.035 h-1, even a ratio of 0.65 between glucose and cyanuric acid was not sufficient to degrade the cyanuric acid supplied (320-540 mumol l-1 h-1) completely . When a continuous two-step system was applied with dilution rates between 0.035 h-1 and 0.056 h-1, the consumption of carbon source could be minimized while s-triazine degradation up to 860 mumol l-1 h-1 was complete . In this way the ratio between glucose and cyanuric acid could be increased to 0.25 (molar C:N ratio = 0.33:1) . Thereby the process was made considerably more economic.

Appl Microbiol Biotechnol, 1995 Apr, 43(1), 109 - 16
Growth behaviour and glucoamylase production by Aspergillus niger N402 and a glucoamylase overproducing transformant in recycling culture without a nitrogen source; Schrickx JM et al.; When wild-type Aspergillus niger N402 and a glucoamylase-overproducing transformant were grown in recycling culture without a nitrogen source, hyphal tip extension and glucoamylase production still occurred, but overproduction of glucoamylase by the transformant strain stopped . The mycelium retained a low metabolic activity . Light micrographs of mycelial samples showed that some hyphae were broken at their tip and partially empty, while after continuing recycling fermentation for more than 500 h many small and empty pieces of broken mycelium could be found . A model has been developed to calculate the mycelial growth and death rates . The mycelial death rate just exceeded the mycelial growth rate and as a consequence the amount of biomass in the fermentor vessel slightly decreased . It is concluded that the cytoplasmic contents of broken mycelial threads were released into the medium and acted as a nitrogen source for the growing parts of the mycelium.

Lett Appl Microbiol, 1995 Apr, 20(4), 252 - 4
Citric acid production by Aspergillus niger in surface culture on inulin; Drysdale CR et al.; Aspergillus niger produces citric acid during surface fermentation on inulin, a reserve carbohydrate of plant tubers . Citric acid yields can be improved by airflow over the surface of the fermentation but yields from inulin are 20-30% lower than from sucrose, the traditional commercial substrate.

Arch Microbiol, 1995 Apr, 163(4), 268 - 75
Electron transport phosphorylation driven by glyoxylate respiration with hydrogen as electron donor in membrane vesicles of a glyoxylate-fermenting bacterium; Friedrich M et al.; The syntrophically glycolate-fermenting bacterium in the methanogenic binary coculture FlGlyM was isolated in pure culture (strain FlGlyR) with glyoxylate as sole substrate . This strain disproportionated 12 glyoxylate to 7 glycolate, 10 CO2, and 3 hydrogen . Glyoxylate was oxidized via the malyl-CoA pathway . All enzymes of this pathway, i.e . malyl-CoA lyase/malate: CoA ligase, malic enzyme, and pyruvate synthase, were demonstrated in cell-free extracts . Glycolate dehydrogenase, hydrogenase, and ATPase, as well as menaquinones as potential electron carriers, were present in the membranes . Everted membrane vesicles catalyzed hydrogen-dependent glyoxylate reduction to glycolate {86-207 nmol min-1 (mg protein)-1} coupled to ATP synthesis from ADP and Pi {38-82 nmol min-1 (mg protein)-1)} . ATP synthesis was abolished entirely by protonophores or ATPase inhibitors (up to 98 and 94% inhibition, respectively) indicating the involvement of proton-motive force in an electron transport phosphorylation driven by a new glyoxylate respiration with hydrogen as electron donor . Measured reaction rates in vesicle preparations revealed a stoichiometry of ATP formation of 0.2-0.5 ATP per glyoxylate reduced.

Appl Environ Microbiol, 1995 Apr, 61(4), 1580 - 5
Purification and partial characterization of an aldo-keto reductase from Saccharomyces cerevisiae; Kuhn A et al.; A cytosolic aldo-keto reductase was purified from Saccharomyces cerevisiae ATCC 26602 to homogeneity by affinity chromatography, chromatofocusing, and hydroxylapatite chromatography . The relative molecular weights of the aldo-keto reductase as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and size exclusion chromatography were 36,800 and 35,000, respectively, indicating that the enzyme is monomeric . Amino acid composition and N-terminal sequence analysis revealed that the enzyme is closely related to the aldose reductases of xylose-fermenting yeasts and mammalian tissues . The enzyme was apparently immunologically unrelated to the aldose reductases of other xylose-fermenting yeasts . The aldo-keto reductase is NADPH specific and catalyzes the reduction of a variety of aldehydes . The best substrate for the enzyme is the aromatic aldehyde p-nitrobenzaldehyde (Km = 46 microM; kcat/Km = 52,100 s-1 M-1), whereas among the aldoses, DL-glyceraldehyde was the preferred substrate (Km = 1.44 mM; kcat/Km = 1,790 s-1 M-1) . The enzyme failed to catalyze the reduction of menadione and p-benzoquinone, substrates for carbonyl reductase . The enzyme was inhibited only slightly by 2 mM sodium valproate and was activated by pyridoxal 5'-phosphate . The optimum pH of the enzyme is 5 . These data indicate that the S . cerevisiae aldo-keto reductase is a monomeric NADPH-specific reductase with strong similarities to the aldose reductases.

J Appl Bacteriol, 1995 Apr, 78(4), 409 - 12
Seeds as natural matrices for immobilization of Aspergillus niger mycelium producing pectinases; Fiedurek J et al.; A simple method for the immobilization of Aspergillus niger mycelium producing polygalacturonase (PG) and pectinesterase (PE) is described . Fungal conidia were immobilized on wheat, rye, barley, peas, buckwheat and mustards seeds . Spongy mycelia overgrowing the seed surfaces on mineral medium with pectin produced extracellular PG and PE; the highest production was reached on the wheat carrier . Some of the variables influencing the enzymatic activity have been optimized . After every 24 h, a culture liquid with 6.8-7.8 U of PG ml-1 and 7.0-10.1 U of PE ml-1 was obtained . This procedure also made possible repeated batch enzyme production and, as many as eight subsequent 24-h batches could be fermented by using the same carrier without any loss of PG activity . The addition of sodium orthovanadate (1 mmol) into the medium with pectin caused a significant increase in PG and PE activity produced by free cells of A . niger (by 1.59-fold and 1.67-fold respectively), and only 0.47-fold of PG activity in case of the immobilized mycelium.

J Bacteriol, 1995 Apr, 177(8), 2002 - 7
Growth of Methanosarcina barkeri (Fusaro) under nonmethanogenic conditions by the fermentation of pyruvate to acetate: ATP synthesis via the mechanism of substrate level phosphorylation; Bock AK et al.; A mutant of Methanosarcina barkeri (Fusaro) is able to grow on pyruvate as the sole carbon and energy source . During growth, pyruvate is converted to CH4 and CO2, and about 1.5 mol of ATP per mol of CH4 is formed (A.-K . Bock, A . Prieger-Kraft, and P . Schonheit, Arch . Microbiol . 161:33-46, 1994) . The pyruvate-utilizing mutant of M . barkeri could also grow on pyruvate when methanogenesis was completely inhibited by bromoethanesulfonate (BES) . The mutant grew on pyruvate (80 mM) in the presence of 2 mM BES with a doubling time of about 30 h up to cell densities of about 400 mg (dry weight) of cells per liter . During growth on pyruvate, the major fermentation products were acetate and CO2 (about 0.9 mol each per mol of pyruvate) . Small amounts of acetoin, acetolactate, alanine, leucine, isoleucine, and valine were also detected . CH4 was not formed . The molar growth yield (Yacetate) was about 9 g of cells (dry weight) per mol of acetate, indicating an ATP yield of about 1 mol/mol of acetate formed . Growth on pyruvate in the presence of BES was limited; after six to eight generations, the doubling times increased and the final cell densities decreased . After 9 to 11 generations, growth stopped completely . In the presence of BES, suspensions of pyruvate-grown cells fermented pyruvate to acetate, CO2, and H2 . CH4 was not formed . Conversion of pyruvate to acetate, in the complete absence of methanogenesis, was coupled to ATP synthesis . Dicyclohexylcarbodiimide, an inhibitor of H(+)-translocating ATP synthase, did not inhibit ATP formation . In the presence of dicyclohexylcarbodiimide, stoichiometries of up to 0.9 mol of ATP per mol of acetate were observed . The uncoupler arsenate completely inhibited ATP synthesis, while the rates of acetate, CO2, and H2 formation were stimulated up to fourfold . Cell extracts of M . barkeri grown on pyruvate under nonmethenogenic conditions contained pyruvate: ferredoxin oxidoreductase (0.5 U/mg), phosphate acetyltransferase (12 U/mg), and acetate kinase (12 U/mg) . From these data it is concluded that ATP was synthesized by substrate level phosphorylation during growth of the M . barkeri mutant on pyruvate in the absence of methanogenesis . This is the first report of growth of a methanogen under nonmethanogenic conditions at the expense of a fermentative energy metabolism.

Am J Clin Nutr, 1995 Apr, 61(4), 792 - 9
Resistant starch in the diet increases breath hydrogen and serum acetate in human subjects; Muir JG et al.; The colonic fermentation of two diets differing in amounts of resistant starch (RS) was studied . High- and low-RS diets were fed to eight healthy subjects in three meals for 1 d . Breath hydrogen and two blood samples were collected over a 28-h period . The high-RS diet provided 59.1 +/- 4.7 g (mean +/- SE) RS and the low-RS diet provided 5.2 +/- 0.4 g RS . Breath hydrogen and the average total serum acetate were significantly higher during the high-RS diet than during the low-RS diet: 34.1 +/- 4.7 and 23.9 +/- 3.9 ppm (P < 0.001) and 169.1 +/- 12.8 and 118 +/- 6.6 mumol/L (P < 0.01), respectively . Butyrate and propionate were also detected in serum samples . Although not statistically significant, there was a trend (P = 0.087) for butyrate to increase with the high-RS diet . Subjects reported greater gastrointestinal symptoms during the high-RS diet . These results suggest that RS may have effects comparable with those of some fermentable dietary fibers.

Electrophoresis, 1995 Apr, 16(4), 642 - 6
Capillary electrophoretic separations of biotechnology-derived proteins in E . coli fermentation broth; Strege MA et al.; A capillary electrophoresis (CE) method was developed for the analysis of a recombinant DNA protein in a fermentation broth matrix . A polyacrylamide-coated capillary was employed to eliminate electroosmotic flow, facilitating relatively rapid run times . Selectivity and efficiency were enhanced significantly through the incorporation of magnesium sulfate and acetonitrile, an organic modifier, into the separation buffer . Both of these additives appeared to influence the separation by diminishing the interaction of the protein analyte with the charged micelles present in the buffer . The quantitation capabilities of the CE method were validated and found to be comparable to the standards set by chromatographic techniques previously developed for similar applications.

Curr Genet, 1995 Apr, 27(5), 409 - 16
NCA3, a nuclear gene involved in the mitochondrial expression of subunits 6 and 8 of the Fo-F1 ATP synthase of S . cerevisiae; Pelissier P et al.; Respiratory-competent nuclear mutants have been isolated which presented a cryosensitive phenotype on a non-fermentative carbon source, due to a dysfunctioning of the mitochondrial F1-Fo ATP synthase which results from a relative defect in subunits 6 and 8 of the Fo sector . Both proteins are mtDNA-encoded, but the defect is due to the simultaneous presence of a mutation in two unlinked nuclear genes (NCA2 and NCA3, for Nuclear Control of ATPase) promoting a modification of the expression of the ATP8-ATP6 co-transcript (formerly denoted AAP1-OLI2) . This co-transcript matures at a unique site to give two cotranscripts of 5.2 and 4.6 kb in length: in the mutant, the 5.2-kb co-transcript was greatly lowered . NCA3 was isolated from a wild-type yeast genomic library by genetic complementation . The level of the 5.2-kb transcript, like the synthesis of subunits 6 and 8, was partly restored in the transformed strain . A 1011-nucleotide ORF was identified that encodes an hydrophilic protein of 35417 Da . Disruption of chromosomal DNA within the reading frame promoted a dramatic decrease of the 5.2-kb mRNA but did not abolish the respiratory competence of a wild-type strain . NCA3 is located on chromosome IV and produces a single 1780-b transcript.

J Nutr Sci Vitaminol (Tokyo), 1995 Apr, 41(2), 179 - 85
Poor fermentability of "mekabu" (sporophyll of Undaria pinnatifida) alginic acid in batch culture using pig cecal bacteria; Togari N et al.; Sodium alginate, mannuronic acid-rich and guluronic acid-rich fractions were prepared from "Mekabu" (sporophyll of Undaria pinnatifida) . The production of short-chain fatty acids such as acetic, propionic and n-butyric acids from these fractions in mini-scale batch culture using pig cecal bacteria was studied, and the gas released from the culture was monitored . The volume of released gas corrected for blank value decreased in the order: glucose (a reference substrate) > guluronic acid-rich fraction > sodium alginate = mannuronic acid-rich fraction . The amounts of short-chain fatty acids produced from three fractions of alginic acid were smaller than that of glucose . These results suggested that alginic acid was poorly fermentable for hindgut bacteria and that its contribution to the host energy pool via microbial metabolism is small.

Dtsch Tierarztl Wochenschr, 1995 Apr, 102(4), 150 - 1
Selective retention of fluid digesta in the hindgut of bandicoots and other marsupial caecum fermenters; Hume ID et al.; Many small hindgut fermenters have a mechanism in the proximal colon that separates fluid and/or bacteria from large particles, and excretes the large particles relatively rapidly . The fluid and/or bacteria are retained in the caecum, which concentrates digestive effort in that region of the hindgut and improves overall digestive efficiency . Previously observed among marsupials only in arboreal marsupials, selective retention of fluid digesta has recently been reported also in bandicoots, small terrestrial omnivores . The separation mechanism operated independently of the nature of the diet, indicating that it is probably an important factor in the ability of bandicoots to switch between insect and plant foods, and thus to exploit nutritionally unpredictable environments . Results are discussed in relation to possible locations in the marsupial hindgut of the pacemaker that in eutherians has been shown to initiate retrograde movement of fluid and small particles in the proximal colon towards the caecum.

Zentralbl Bakteriol, 1995 Apr, 282(3), 232 - 6
Additional tests to differentiate Arcanobacterium haemolyticum and Actinomyces pyogenes; Carlson P et al.; A commercially available biochemical test panel, commercially available diagnostic tablets and gas-liquid chromatography (GLC) of cellular fatty acids were used to find out whether Arcanobacterium haemolyticum and Actinomyces pyogenes could be further differentiated from each other . Xylitol and alpha-methyl-D-glucoside fermentation, Voges-Proskauer reaction and tributyrate hydrolysis were found to be useful additional tests which differentiated Arc . haemolyticum and A . pyogenes . GLC analysis revealed major differences in the cellular 16:0, 18:2(9,12) and 18:1(9) fatty acid composition of the two species . Especially the Voges-Proskauer test available as diagnostic tablets can be easily performed in clinical microbiology laboratories, in addition to the tests now used to differentiate Arc . haemolyticum from A . pyogenes.

Int J Syst Bacteriol, 1995 Apr, 45(2), 348 - 50
Taxonomic analysis of the tortoise mycoplasmas Mycoplasma agassizii and Mycoplasma testudinis by 16S rRNA gene sequence comparison; Brown DR et al.; The nucleotide sequences of the 16S rRNA genes of two mycoplasmas, Mycoplasma agassizii (proposed sp . nov.) and Mycoplasma testudinis, isolated from tortoises were determined and used for taxonomic comparisons . Signature nucleotide sequence motifs and overall sequence similarities to other mollicutes positioned these mycoplasmas in the M . hyorhinis and M . pneumoniae phylogenetic groups, respectively . A third, previously unrecognized tortoise mycoplasma was detected by 16S rRNA gene amplification and sequence analysis and was positioned in the M . fermentans phylogenetic group . The 16S rRNA gene of Acholeplasma laidlawii was similarly detected in a tortoise isolate, showing that diverse mollicutes can share the same family of reptilian host.

Int J Syst Bacteriol, 1995 Apr, 45(2), 297 - 300
Succiniclasticum ruminis gen . nov., sp . nov., a ruminal bacterium converting succinate to propionate as the sole energy-yielding mechanism; van Gylswyk NO; A gram-negative, anaerobic, nonmotile, non-spore-forming, rod-shaped bacterium that fermented succinate quantitatively to propionate was isolated from a high dilution of rumen ingesta obtained from a dairy cow fed a production diet containing grass silage as the main roughage source . This organism did not grow on any of the following energy sources: 12 carbohydrates, pyruvate, lactate, 7 dicarboxylic acids, aspartate, citrate, and trans-aconitate . Both rumen fluid and yeast extract were necessary for good growth on succinate . The organism was negative for the following characteristics: production of propionate from threonine, protein digestion, sulfide production, nitrate reduction, catalase activity, and urease activity . There was no growth at 22 degrees C and reduced growth at 45 degrees C compared with growth at 39 degrees C . The DNA base composition was 52 mol% G + C . The complete 16S rRNA sequence (EMBL accession number, X81137) was obtained, and the phylogenetic relationships of the organism were determined . The most closely related genera were the genera Acidaminococcus and Phascolarctobacterium . The name proposed for this bacterium is Succiniclasticum ruminis gen . nov., sp . nov.; the type strain is strain SE10 (= DSM 9236) . Additional isolation attempts revealed that S . ruminis is a common inhabitant of the rumina of cows that are fed production diets and of cows on pasture.

Wei Sheng Wu Xue Bao, 1995 Apr, 35(2), 103 - 8
{Physicochemical properties of a beta-glucan from Sclerotinia sclerotiorum}; Liu R et al.; Sclerotan (SSG) was an extracellular polysaccharide from Sclerotinia sclerotiorum by submerged fermentation . It had potential immunomodulating and antitumor activity . The SSG was a glucan composed of beta-linked D-glucoses . It was hard to dissolve in water under normal condition, but its aqueous solution had fine rheological properties . Its intrinsic viscosity {eta} hardly changed with ionic strenth . Change of its {eta} value was not remarkable between pH 1.88-12.36 . Nevertheless, when the pH came to 13.32, the {eta} value decreased rapidly due to change of molecules conformation . Effect of temperature < or = 90 degrees C and heat treatment on apparent viscosity of SSG solution was minor.

J Nutr, 1995 Mar, 125(3 Suppl), 570S - 572S
Traditional soyfoods: processing and products; Golbitz P; Although soyfoods have been consumed for more than 1000 years, only for the past 15 years have they made an inroad into Western cultures and diets . Soyfoods are typically divided into two categories: nonfermented and fermented . Traditional nonfermented soyfoods include fresh green soybeans, whole dry soybeans, soy nuts, soy sprouts, whole-fat soy flour, soymilk and soymilk products, tofu, okara and yuba . Traditional fermented soyfoods include tempeh, miso, soy sauces, natto and fermented tofu and soymilk products . This paper presents a brief overview of processing techniques used in the manufacture of traditional soyfoods.

Exp Cell Res, 1995 Mar, 217(1), 52 - 6
Carbon and energy uncoupling associated with cell cycle arrest of cdc mutants of Saccharomyces cerevisiae may be linked to glucose-induced catabolite repression; Monaco ME et al.; Several cell division cycle (cdc) mutants of Saccharomyces cerevisiae (cdc28, cdc35, cdc19, cdc21, and cdc17) at the restrictive temperature (37 degrees C) in the presence of 1% glucose and defined medium divert most of the carbon (approximately 50%) to ethanol production with low biomass growth yields (Yglc) that correlate with carbon and energy uncoupling and arrest of cell proliferation . The cdc mutants studied are shown to be glucose-repressed, while this was not the case for the wild-type A364A (WT) . At 37 degrees C, in the presence of 1% glycerol, derepressed cdc28 mutant cells did not show arrest of cell division and carbon and energy uncoupling since the Yglc levels measured were similar to those of the WT strain . These results suggest that the increased fermentative ability and carbon and energy uncoupling exhibited in the presence of glucose by cdc mutants with respect to those exhibited by the WT may be due to catabolite repression.

Exp Cell Res, 1995 Mar, 217(1), 42 - 51
Carbon and energetic uncoupling are associated with block of division at different stages of the cell cycle in several cdc mutants of Saccharomyces cerevisiae; Aon MA et al.; Cell proliferation arrest at 37 degrees C (restrictive temperature) of the cell division cycle (cdc) mutants of Saccharomyces cerevisiae cdc28, cdc35, cdc19, cdc21, and cdc17 was correlated with carbon and energy uncoupling . At 37 degrees C, cdc mutants diverted to biomass synthesis only 3 to 4% and 8 to 24% of the fluxes of carbon consumed and ATP obtained by catabolism, respectively, compared with 48 and 34% in the wild-type strain A364A . At the permissive temperature (25 degrees C), the wild type showed similar carbon and energy coupling indexes as at 37 degrees C . However, carbon and energy coupling indexes were two- to sevenfold higher at 25 degrees than at 37 degrees C in cdc mutants; e.g., at 25 degrees C two- to sevenfold higher amounts of carbon and ATP were directed to biomass production than at 37 degrees C . The wild-type strain exhibited a purely oxidative glucose catabolism at 37 degrees C (RQ approximately 1.0), while the cell proliferation arrest of cdc mutants at the same temperature was characterized by fermentative metabolism . At 37 degrees C, cdc mutants directed 50 to 60% of the carbon to ethanol production; 3 to 12% of the carbon was recovered as glycerol in cdc mutants as well as in the wild type . The proliferation arrest of the cell division cycle mutant cdc28 correlated with a significant decrease in the incorporation of radioactive precursors into DNA, RNA, and proteins . In the presence of 8-hydroxyquinoline, the wild-type strain underwent cell proliferation arrest and also exhibited metabolic uncoupling with bioenergetic and catabolic behavior similar to that of the cdc mutants at 37 degrees C . Experimental evidence obtained with cdc19, whose defective gene product is pyruvate kinase, suggests that the primary defect of cdc mutants correlates with a metabolically, highly uncoupled yeast cell . The results presented point to the existence of strong carbon and energy uncoupling together with cell division arrest exhibited by cdc mutants at the restrictive temperature . The degree of uncoupling appears to be tuned, at least in part, by the increase in flux of sugar catabolism through the ethanol fermentative pathway.

Plant Mol Biol, 1995 Mar, 27(6), 1235 - 40
Differential expression of two barley SNF1-related protein kinase genes; Hannappel U et al.; We have amplified and cloned DNA sequences derived from a gene encoding a SNF1 (sucrose-non-fermenting 1)-related protein kinase which differs from that previously reported from barley . Northern blot and polymerase chain reaction (PCR) analysis of RNA populations, using specific probes and oligonucleotide primers, indicated that the two SNF1-related genes are differentially regulated . One is expressed in all tissues, whereas the other is expressed at high levels in the seed endosperm and aleurone, but at levels undetectable by northern blot analysis in other tissues . Comparisons with other plant SNF1-related protein kinase genes suggest that the form which is expressed at greatly enhanced levels in the seed is less similar to the other plant homologues which have been reported and may be unique to cereals.

Br J Nutr, 1995 Mar, 73(3), 423 - 32
Replacement of digestible by resistant starch lowers diet-induced thermogenesis in healthy men; Heijnen ML et al.; The present study describes the effect of replacement of digestible starch by resistant starch (RS) on diet-induced thermogenesis (DIT), postprandial glucose and insulin responses, and colonic fermentation . Ten healthy males consumed three test meals, consisting of diluted, artificially-sweetened fruit syrup and either 50 g raw potato starch (550 g RS/kg), or 50 g pregelatinized potato starch (0 g RS/kg) or 30 g pregelatinized potato starch plus 20 g lactulose (670 g indigestible disaccharide/kg) . The meals were served in the morning after an overnight fast . Each volunteer consumed each meal twice on six separate days in random order . Metabolic rate was measured by indirect calorimetry in the fasting state for 15 min and postprandially for 5 h . Shortly before and hourly up to 7 h after consumption of the test meal, end-expiratory breath samples were obtained for H2 and CH4 analysis . Shortly before the meal and 30, 60, 180, and 300 min postprandially, blood samples were taken for glucose and insulin analyses . Postprandial increases in glucose and insulin levels were proportional to the amount of digestible carbohydrate in the meal . Breath H2 and CH4 concentrations indicated that the pregelatinized starch was not fermented and that lactulose was fermented rapidly . Fermentation of the raw starch started only 6 to 7 h after consumption, resulting in a rise in breath H2 but not in CH4 . The replacement of 27 g digestible starch by RS in a single meal lowered DIT by on average 90 kJ/5 h, as could also be calculated by assuming that RS does not contribute to DIT . The ingestion of lactulose resulted in a substantial rise in DIT which was most probably caused by its fermentation.

Z Naturforsch {C}, 1995 Mar-Apr, 50(3-4), 173 - 80
Collybial, a new antibiotic sesquiterpenoid from Collybia confluens (Basidiomycetes); Simon B et al.; A new antibiotic was isolated from fermentations of an american strain of Collybia confluens . Its structure was elucidated by spectroscopic methods as 2,10,10-trimethal-4-oxo-tricyclo{7.2.0.0(2.5)}undec-6- en-carbaldehyde (with the relative stereo chemistry 1S, 2R, 5R, 9R) (1) . The inhibitor, which was named collybial, is structurally related to koraiol, a sesquiterpenoid isolated from Pinus koraiensis (Khan V . A . (1979), Khim . Prir . Soedin 5, 652-658) . Collybial inhibited the growth of Gram-positive bacteria at concentrations starting from 21.5 microM . The propagation of vesicular stomatitis virus (VSV) in baby hamster kidney (BHK-21) cells was inhibited by 21.5 microM collybial . Cytotoxic effects on BHK cells were observed at 5 fold higher concentrations.

Appl Microbiol Biotechnol, 1995 Mar, 42(6), 860 - 4
Expression of Saccharomyces adenylate kinase gene in Candida boidinii under the regulation of its alcohol oxidase promoter; Sakai Y et al.; The methylotrophic yeast, Candida boidinii, was investigated as a new efficient host for heterologous gene expression . The Saccharomyces cerevisiae adenylate kinase gene (ADK1) was used as the first example for heterologous enzyme production in C . boidinii . C . boidinii cells were transformed with plasmids harboring the S . cerevisiae ADK1 gene under the alcohol oxidase (C . boidinii AOD1) promoter . The chromosome-integrant strains produced adenylate kinase protein corresponding to 22%-28% of the total soluble proteins in an enzymatically active form . When the three-copy integrative transformant was grown for 60 h on methanol-glycerol medium in a 1.5-l jar fermentor, adenylate kinase was produced intracellularly with a yield of up to 2 milligrams culture medium . As the expression of the S . cerevisiae ADK1 in C . boidinii was under similar regulation to that of the C . boidinii AOD1, the previously cloned 1.7-kb AOD1 promoter fragment was proved to harbor sufficient cis elements for AOD1 regulation and found to be an efficient promoter for heterologous gene expression.

Prikl Biokhim Mikrobiol, 1995 Mar-Apr, 31(2), 238 - 42
{Composition and biological activity of steroid glycosides from a suspended culture of Dioscorea deltoidea Wall cells}; Vasil'eva IS et al.; Two major steroid spirostanol glycosides (oligospirostanosides): deltoside (melting point, 296 degrees C, {alpha}D10:-90.8 degrees C (c 5.0,Py) and dioscine (melting point, 285-285 degrees C, {alpha}D10:-106.5 degrees C (c 5.0, Py) and a minor glycoside diosgenin-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside were isolated form cell suspensions of Discorea deltoidea after fermentation with beta-glucosidase . The cell suspensions contained these glycosides as the furostanol analogs (oligofurostanosides) deltoside, protodioscine, and delta 5-furosten-3 beta,22,26-triol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D- glucopyranoside . The native oligofurostanosides isolated from D . deltoidea cell suspensions have a high biological activity and can be used as phytobiostimulators in medicine, veterinary, and agriculture.

ISA Trans, 1995 Mar, 34(1), 3 - 19
Development of biotechnology control systems; Romeu FJ; Advances in genetic engineering have generated great interest in biotechnology systems . Modern fermentation processes have a more scientific basis and can be optimized more quickly by utilizing instrumentation and control technology that permits increasing yield and product quality . The automation technology, to a large extent, can determine the degree of success of growing microorganisms . The automation system in modern biotechnology facilities includes a number of leading technologies such as sensors, indicators, data acquisition, distributed control, programmable control, communications, data base management, on-line data analysis techniques and application software . Modern computer systems have made fermentation processes easier and more accurate by performing tasks such as on-line analysis, statistical process control and supervisory control, while microprocessor-based distributed process controllers perform direct digital control, batch and sequencing control . This paper addresses technical issues related to the development of instrumentation and control systems that integrate these technologies through methodologies that permit the timely generation of the documentation and drawings that specify the control system for procurement, installation, commissioning, validation and operation.

J Antibiot (Tokyo), 1995 Mar, 48(3), 211 - 6
Terpentecin and ECT4B, new family of topoisomerase II targeting antitumor antibiotics produced by Streptomyces: producing organism, fermentation and large scale purification; Kawada S et al.; Terpentecin and UCT4B are new family of antitumor antibiotics with topoisomerase II mediated DNA cleavage activity . Based on the taxonomic studies, the producing strain S-464 was identified as Streptomyces sp . This strain is different from Kitasatosporia griseola which had been identified as the terpentecin-producing strain in 1988 . Fermentation studies showed that natural nitrogen sources supported higher titer of terpentecin, and the synthetic medium with inorganic nitrogen sources supported selective production of UCT4B . An improved isolation method was developed for the large scale purification of terpentecin.

J Antibiot (Tokyo), 1995 Mar, 48(3), 191 - 8
Paeciloquinones A, B, C, D, E and F: new potent inhibitors of protein tyrosine kinases produced by Paecilomyces carneus . I . Taxonomy, fermentation, isolation and biological activity; Petersen F et al.; Paeciloquinones A to F as well as versiconol have been isolated as inhibitors of protein tyrosine kinase from the culture broth of the fungus Paecilomyces carneus P-177 . The novel anthraquinones inhibit epidermal growth factor receptor protein tyrosine kinase in the micromolar range . Two compounds, paeciloquinones A and C, are potent and selective inhibitors of the v-abl protein tyrosine kinase with an IC50 of 0.4 microM . Dependent on the fermentation conditions, partially different sets of paeciloquinones may be produced . An HPLC method allows separation of all major active components.

FEMS Microbiol Lett, 1995 Mar 1, 126(3), 263 - 9
Construction of a recombinant wine yeast strain expressing a fungal pectate lyase gene; Gonzalez-Candelas L et al.; A gene fusion between the Saccharomyces cerevisiae actin gene promoter and the cDNA of the Fusarium solani f . sp . pisi pelA gene has been constructed . This expression cassette has been introduced into the industrial wine yeast strain T73 . The resulting recombinant strain is able to secrete active PELA enzyme into the culture medium . In preliminary microvinification experiments the wine produced by this pectinolytic strain is indistinguishable from wine produced using the non-transformed strain on the basis of the chemical analyses . Large scale fermentations need to be carried out in order to assess the effects on filtrability.

Comp Biochem Physiol A Physiol, 1995 Mar, 110(3), 243 - 52
Mineral absorption and secretion patterns in the alimentary tract of the roe deer (Capreolus capreolus); Holand O et al.; Concentrations of macrominerals; Na, K, Ca, Mg, P, and Cl were measured in different sections of the alimentary tract of five roe deer, Capreolus capreolus, kept in captivity and fed a diet of grass pellets and oats . By means of the non-absorbed marker-slaughter technique (using 51CrEDTA as marker), sites of secretion and absorption of minerals in the alimentary tract were determined . Large amounts of P, Na and K were secreted into the rumen, whereas Cl was secreted into the abomasum . The larger amounts of these minerals were absorbed from the distal small intestine and caecum/proximal colon . In the coiled colon, small quantities of Na, K and Cl were absorbed which is essential for the maintenance of mineral balance . Emphasis is put on the role of the large hindgut in concentrate selectors both with respect to fermentation and conservation of minerals and other nutrients.

Carcinogenesis, 1995 Mar, 16(3), 471 - 6
Possible anti-tumour-promoting activity of components in Japanese soybean fermented food, Natto: effect on gap junctional intercellular communication; Takahashi C et al.; In order to detect any protective agent against tumor formation, we examined the anti-tumor-promoting effect of a Japanese traditional soybean fermented food, Natto . Dye transfer was employed as an assay method . When fluorescent dye was microinjected into cultured BALB/3T3 cells, the dye was transformed into the neighboring cells through the gap junction . This dye transfer was blocked by the treatment with the tumor promoters 12-O-tetra-decanoylphorbol-13-acetate (TPA), a high concentration of NaCl and lithocholic acid (LCA) . This reduction of the dye transfer by TPA treatment was not observed when the cells were pretreated with retinoic acid, an anti-tumor promoter . Thus, the recovery of the dye transfer in TPA-treated BALB/3T3 cells was proven to ge a good indicator for detecting some possible anti-tumor promoters . After extraction and fractionation of Natto, we obtained an active fraction (H1) which showed recovery of the dye transfer in TPA-treated cells . The fraction contained straight-chain saturated hydrocarbons . A comparison of the fraction and the authentic samples by GC analysis suggests that the H1 fraction contained straight-chain saturated hydrocarbons from around C30 to C32 . Among these hydrocarbons, hentriacontane (C31) was found at the highest concentrations, and was shown to have the highest activity . Hentriacontane at a very low concentration of 0.65 ng/ml was shown to recover the dye transfer inhibited by the treatment with TPA as well as with NaCl and LCA.

Mikrobiol Z, 1995 Mar-Apr, 57(2), 31 - 40
Possible monosaccharide composition of glycopolymers located on the external side of membranes of cells of some mollicutes; Skripal' IG et al.; Monosaccharide composition of glycopolymers of five mollicutes (Mycoplasma pneumoniae FH, M . hominis PG 21, M . fermentans PG 18, Acholeplasma laidlawii PG 8 and A . laidlawii var . granulum 118) integrated with their membrane has been studied by means of nine plant lectins with certain carbohydrate specificity labelled with colloid gold . Monosaccharide composition of glycopolymers depends both on the mollicute species and on its capacity to evoke diseases in different microorganisms . Thus genetically relative A . laidlawii PG 8 (saprophytic microorganism) and A . laidlawii var . granulum 118 (an agent of pale-green dwarfness of cereals) have the ratio between N-acetyl-D . galactosamine and N-acetyl-D-glucosamine 2:1 and 1:2, respectively . Large amounts of such exotic sugar as L-fucose have been found in M . hominis PG 21, M . fermentans PG 18 and A . laidlawii PG 8 . L-fucose plays the basic role in disguising cells of these mollicutes in human organism (as O(H)-group blood erythrocytes), which permits these mollicutes disseminating through the whole organism . The composition of extracellular glycopolymers of mollicutes is discussed to reveal their role in the processes of adhesion and specialization (organotropism) of these microorganisms in populating the corresponding organs and tissues of macroorganisms.

J Am Mosq Control Assoc, 1995 Mar, 11(1), 39 - 44
Oviposition responses of Culex tarsalis and Culex quinquefasciatus to aged Bermuda grass infusions; Isoe J et al.; Fermented infusions of organic matter are commonly used as baits in traps for gravid female mosquitoes . However, infusions are dynamic, and their effects on mosquito oviposition as their chemical and microbial constituents change over time are not well documented . Bermuda grass infusion fermented for periods of 0-63 days was stimulatory to gravid Culex quinquefasciatus . In contrast, only 5-25-day-old infusion was stimulatory to Culex tarsalis . Standard-aged infusion (7 days old) was as effective or better than infusion of any other age for Cx . tarsalis, whereas Cx . quinquefasciatus exhibited a distinct preference for 2-4-wk-old infusion . The results are discussed in terms of mosquito species' oviposition site preferences and in terms of mosquito surveillance programs.

J Am Mosq Control Assoc, 1995 Mar, 11(1), 21 - 8
Characterization of factors mediating oviposition site choice by Culex tarsalis; Isoe J et al.; Fermented infusions of organic matter were tested for their effects on Culex tarsalis oviposition . Bermuda grass infusion and polluted water collected from a natural oviposition site (La Brea tar pits, CA) enhanced oviposition rates, but an alfalfa infusion and water from a 2nd natural oviposition site (Prado Basin, CA) did not . Bermuda grass infusion was fractionated by dialysis and filter sterilization . Crude Bermuda grass infusion, and fractions of the infusion containing large molecules (> 12,000 daltons), particulates, and microorganisms significantly increased oviposition rates compared to distilled water controls . The fraction containing small molecules was no better than a distilled water control, suggesting that small molecules are not involved in oviposition stimulation in this species . However, using the egg raft counting bioassay, the possibility that the small molecules fraction contained oviposition attractants could not be ruled out . Overall, our experiments suggest that results obtained with the egg raft counting bioassay, which has been used frequently to screen for oviposition attractants, should be interpreted with caution . High oviposition rates in this bioassay may be due to responses to factors such as nonvolatile, contact oviposition stimulants rather than to volatile attractants.

JPEN J Parenter Enteral Nutr, 1995 Mar-Apr, 19(2), 100 - 6
Effect of fiber and its fermentation on colonic adaptation after cecal resection in the rat; Kelberman I et al.; BACKGROUND: The role of fiber in postresection adaptation is poorly understood . We examined the significance of short-chain fatty acids produced by intracolonic fiber fermentation during colonic adaptation . METHODS: Rats underwent one of three surgeries: control laparotomy, cecal resection, or cecal resection with placement of perfusion catheter . Rats of each surgical group were randomly assigned to receive treatment regimens of standard fiber diet (with or without fermentation-suppressing antibiotics), fiber-free diet, or diet plus intracolonic perfusion of short-chain fatty acids . Adaptation parameters of mucosal weight, mucosal DNA and protein content, water absorption, and butyrate absorption were measured . RESULTS: Compared with controls, postresection rats that were fed fiber had 65% greater basal and 112% greater butyrate-stimulated water absorption as well as 140% greater butyrate absorption . Fiber-fed rats exhibited significantly greater colonic weight and colonic mucosal protein after cecal resection . These changes were absent in postresection rats fed a fiber-free diet . Inhibition of fermentation by neomycin and metronidazole added to a standard fiber diet also prevented postresection adaptation . All adaptive changes were restored when the cecal-resection rats that were fed the fiber diet with antibiotics received an intracolonic infusion of short-chain fatty acids . Adaptation did not occur when short-chain fatty acids were infused into colons of postresection rats that were fed a fiber-free diet . CONCLUSIONS: Cecal resection leads to significant functional and structural changes in the adapting residual colon . Fermentation of dietary fiber by colonic flora to short-chain fatty acids is necessary, but it alone is not sufficient to mediate adaptation.

J Anim Sci, 1995 Mar, 73(3), 818 - 23
Butylsoyamide protects soybean oil from ruminal biohydrogenation: effects of butylsoyamide on plasma fatty acids and nutrient digestion in sheep; Jenkins TC; Based on previous results showing partial resistance of fatty acyl amides to ruminal biohydrogenation, butylsoyamide was added to sheep diets in an attempt to increase unsaturation of plasma fatty acids . Twelve wethers averaging 34 +/- 3.2 kg BW were randomly assigned to three diets containing either no added fat (control), 5% soybean oil, or 5% butylsoyamide . Dry matter intake was greater (P < .05) for sheep fed butylsoyamide than for sheep fed soybean oil (740 and 581 g/d, respectively), but neither fat supplement differed from the control diet (680 g/d) . The soybean oil supplement reduced (P < .05) total VFA concentration (59.0 and 38.7 mM) and acetate:propionate (4.10 and 2.56) in ruminal samples compared with the control diet . Butylsoyamide had no effect (P > .05) on total VFA (54.4 mM) or acetate:propionate (2.96) . Total tract ADF digestibility was not affected (P > .05) by either fat supplement . Relative to the control diet, soybean oil increased (P < .05) plasma linoleic acid concentration 22% compared with a 58% increase from feeding butylsoyamide (26.7, 32.6, and 42.1% of total fatty acids, respectively) . Linoleic acid concentration in plasma neutral lipids, relative to the control diet, increased 15.8% (P < .05) for soybean oil compared with 64.9% (P < .05) for butylsoyamide (31.6, 36.6, and 52.1% of total fatty acids, respectively) . Converting soybean oil triglycerides to fatty acyl amides substantially reduces negative effects of the oil on ruminal fermentation and increases unsaturated fatty acids in plasma . The increase in plasma unsaturated fatty acids demonstrates at least partial resistance of fatty acyl amides to ruminal biohydrogenation and their digestion and absorption postruminally.

Res Microbiol, 1995 Mar-Apr, 146(3), 227 - 36
Growth phase-dependent variations in the outer membrane protein profile of Brucella melitensis; Gallot-Lavallee T et al.; Changes in Brucella cell envelope protein profiles were investigated with batch cultures of B . melitensis strain 16M in a 2-litre fermenter . Analysis of expression of outer membrane proteins (OMP) (apparent molecular masses of 10, 16.5, 19, 25-27, 31-34, 36-38 and 89 kDa) and heat-shock protein DnaK (73 kDa) was performed with monoclonal antibodies (mAb) and immunoblotting techniques . Synthesis of the 89-kDa OMP and the heat-shock protein DnaK was invariant during B . melitensis growth . Expression of the 10-, 19- and 36-38-kDa minor OMPs was never detected . Variations in profiles of some OMPs, i.e . 25-27-kDa and 31-34-kDa major proteins and 16.5-kDa minor protein, occurred during growth stages, principally at the end of the exponential growth phase . These variations consisted of shifts in apparent molecular masses for the 25-27-kDa and 31-34-kDa OMPs and of peptidoglycan association for the 16.5-kDa OMP . Therefore, whereas the strong association of major OMPs with peptidoglycan was confirmed, results suggested that the 16.5-kDa minor OMP is also a peptidoglycan-associated protein.

Microbiologia, 1995 Mar, 11(1), 67 - 74
{Applications of molecular biology in the wine industry}; Ramon D et al.; Population dynamics of natural and inoculated industrial wine fermentations have been studied by using a simple molecular biology technique based on mitochondrial DNA restriction analysis profile . The predominance of the inoculated strain in the inoculated fermentations is obvious . A genetic transformation system has been developed for an industrial wine yeast strain named T73 . By using this technique, different fungal hydrolases in this industrial strain have been expressed . Problems and benefits of the application of recombinant DNA techniques in wine yeast strains are also discussed here.

Microbiologia, 1995 Mar, 11(1), 43 - 50
{Microbiological aspects of sparkling wine processing}; Bartra E; The production of cava (sparkling wine produced according to the rules of the cava appellation, in i.e . Catalonia and La Rioja, Spain) involves several microbial factors such as growth, fermentation and death of yeast cells (Saccharomyces cerevisiae) . Ethanol tolerance, flocculation and aroma characteristics of yeast cells as major selection factors for the production of cava are discussed in this review.

Biochim Biophys Acta, 1995 Feb 22, 1247(1), 90 - 6
An extremely thermostable aromatic aminotransferase from the hyperthermophilic archaeon Pyrococcus furiosus; Andreotti G et al.; Pyrococcus furiosus is a strictly anaerobic archaeon (formerly archaebacterium) that grows optimally at 100 degrees C by the fermentation of peptides . Cell-free extracts were found to contain two distinct aromatic aminotransferases (ArAT, EC 2.6.1.57), one of which was purified to electrophoretic homogeneity . P . furiosus ArAT is a homodimer with a subunit M(r) value of 44,000 +/- 1000 . Using 2-ketoglutarate as the amino acceptor, the purified enzyme catalyzed the pyridoxal 5'-phosphate (PMP)-dependent transamination of phenylalanine, tyrosine and tryptophan with respective kcat values of 253, 72 and 62 (s-1 at 80 degrees C) under saturating conditions . The Km values for all three amino acids were between 1.1 and 2.1 mM and the optimum temperature for catalysis was above 95 degrees C . The melting point for the pure enzyme was also above 95 degrees C as determined by the change in ellipticity at 220 nm . Irreversible denaturation of the pure enzyme was not apparent after 6 h at 80 degrees C in the presence of PMP and 2-ketoglutarate and the time required for a 50% loss in activity at 95 degrees C was approx . 16 h . This decreased to approx . 12 h if cofactor and substrate were not added . In contrast, the apoenzyme (lacking PMP) lost most (70%) of its activity (measured after reconstitution) after 6 h at 80 degrees C, indicating that both PMP and 2-ketoglutarate stabilize the enzyme at extreme temperatures . Although few ArATs have been characterized to date, the molecular properties and substrate specificity of P . furiosus ArAT more resemble those of the ArAT from Escherichia coli than those of the analogous enzyme from rat liver . Moreover, the P . furiosus enzyme is by far the most thermostable aminotransferase of any type to be purified so far.

J Chromatogr B Biomed Appl, 1995 Feb 17, 664(2), 415 - 20
Determination of portal short-chain fatty acids in rats fed various dietary fibers by capillary gas chromatography; Murase M et al.; A simple, rapid and sensitive capillary gas chromatographic method was investigated to measure portal short-chain fatty acids (SCFAs) . A 20-microliters sample of portal plasma was denatured with sulfosalicylic acid and then extracted with diethyl ether before the removal of protein precipitate . The resultant extract was concentrated by a transfer to 50 microliters of 0.2 M NaOH, thus avoiding tedious further concentration steps . This reduced the sample volume to one-fourth . Since the ratio of acetic acid, a major SCFA, to other acids varies widely, ranging from 10-fold to 100-fold, acrylic and methacrylic acids were used as internal standards to simultaneously measure SCFAs having a carbon number of 2-6 . As a result, good recovery (90.38-103.17%) and reproducibility (coefficient of variation 0.83-8.85%) were observed over a wide range . Furthermore, portal SCFAs in rats fed various dietary fibers were determined by the present method . We showed that the amounts not only of the major acids such as acetic acid and propionic acid, but also of the minor fermented products such as n-valeric acid and n-caproic acid, could be significantly changed by dietary manipulation . Thus, the present method is simple and reliable, and requires only a small amount of sample.

FEMS Microbiol Lett, 1995 Feb 15, 126(2), 145 - 50
Genome structure and nucleotide sequence of a lipolytic enzyme gene of Aspergillus oryzae; Ohnishi K et al.; Aspergillus oryzae, which is widely used for Japanese traditional fermentation, produced at least two lipolytic enzymes (L1 and L2) . Southern hybridization analysis of restriction enzyme-digested genomic DNA fragments of Aspergillus oryzae with 23-mer oligonucleotides synthesized according to the amino acid sequence of the enzyme L1 as probes suggested that there is single copy of the L1 gene in the genome . DNA fragments containing the L1 gene were cloned in Escherichia coli . Nucleotide sequencing of the DNA fragments revealed an open reading frame consisting of 213 amino acid residues . It had three putative introns whose sizes were 52 bp, 48 bp and 53 bp, respectively . Putative CAAT and TATA boxes were found at positions -147 and -100 from A (+1) of the translational initiation codon, and a polyadenylation site at 158 bp downstream of the stop codon . The deduced amino acid sequence of the L1 gene was highly similar to those of cutinases from phytopathogenic fungi . Thus, it is interesting to note that the non-phytopathogenic fungus, A . oryzae, produces cutinase, which seems to play an important role in flavor formation.

J Chromatogr B Biomed Appl, 1995 Feb 3, 664(1), 107 - 18
Laboratory-scale production and purification of recombinant HIV-1 reverse transcriptase; Koller G et al.; HIV-1 reverse transcriptase from the HIV-1 strain WMF 1.13 was expressed in Escherichia coli JM 105 using a pKK233-2 vector . The bacteria were cultivated in a 20-l fermentor with 14-l net volume using M9ZB medium containing bactotryptone and yeast extract . After induction of reverse transcriptase (RT) expression by addition of isopropyl-beta-D-thiogalactopyranoside the enzyme concentration was monitored . Both soluble and inclusion-body deposited RT were detected by Western blots . Inclusion-body formation was confirmed by transmission electron microscopy . Further purification of soluble and insoluble RT was investigated . After cell desintegration by enzymatic treatment combined with osmotic shock and centrifugation, the supernatant was desalted by size-exclusion chromatography and further purified by DEAE-Sepharose FF, AF-Heparin Toyopearl 650 M and Fractogel EMD TMAE 650 (S) . The results of the purification steps were monitored by SDS-PAGE with silver staining, non-radioactive RT assay and protein determination with Coomassie Blue . The sediment was extracted with 6 M GuHCl and after clarification and conventional refolding, treated in the same manner as soluble RT . This method is well suited for studying fermentation conditions as well as purification conditions . The RT is expressed in approximately equal amounts as soluble and insoluble enzyme.

Hindustan Antibiot Bull, 1995 Feb-Nov, 37(1-4), 51 - 65
Microbial production of L-tyrosine: a review; Maiti TK et al.; Microbial production of L-tyrosine by direct fermentation and by enzymatic methods has been reviewed . Achievements in this regard made through recombinant DNA techniques have also been included . The review also includes biosynthesis and regulation of tyrosine.

Hindustan Antibiot Bull, 1995 Feb-Nov, 37(1-4), 25 - 36
Aryl beta-galactosidase from Sclerotium rolfsii: physiological and biochemical studies; Bhosale JH et al.; Production of beta-galactosidase by Sclerotium rolfsii NCIM 1084 was studied under submerged fermentation conditions . The enzyme was produced extracellularly and constitutively on glucose . The enzyme production was enhanced when galactose, raffinose, cellobiose, sucrose, xylose, maltose, cellulose and pectin were used as carbon sources . Cellulose and diammonium hydrogen phosphate were best carbon and nitrogen sources, respectively . Surfactants such as Sag, Paraffin oil, Tween 20 and Tween 80 increased the enzyme production . Maximum yield of beta-galactosidase obtained was 3.8-4.2 nkat/ml . The optimum pH, optimum temperature and molecular weight of the beta-glactosidase were 2.7, 60 degrees C and 2,21,000 daltons, respectively . The enzyme is an aryl beta-glactosidase and did not hydrolyse lactose . The Km value for o-nitrophenyl beta-D-galactoside was 3.7 mM . Galactose and 2-mercaptoethanol inhibited the enzyme.

Voen Med Zh, 1995 Feb, (2), 30 - 2, 80
{Gouty visceropathies}; Nenasheva TM; The state of internal organs was studied in 447 patients with primary gout . Clinical, biochemical and instrumental methods were used during these researches . Alterations in kidney were found in 332 patients (74.7%), including 95 with signs of nephritic insufficiency . Pathology of kidney and biliary tract was marked in 187 (41.8%) patients . Multifunctions of fermental, lipid and protein exchange were also disclosed . During computer tomography and USI different alterations in kidney, liver, spleen and pancreas were diagnosed, such as cysts and round calcification . Gallstones were found in 57 patients and stones in kidney--in 164.

Eur J Biochem, 1995 Feb 1, 227(3), 897 - 902
An unusual polar lipid from the cell membrane of Mycoplasma fermentans; Deutsch J et al.; The major unidentified polar lipid (compound X), recently demonstrated in the cell membrane of Mycoplasma fermentans, was purified by preparative silicic acid column chromatography . Chemical analyses of acid-hydrolyzed compound X revealed that, in addition to fatty acids, it contains glycerol, choline and phosphate in a molar ratio of approximately 1:1:2, and an amino acid that has a retention time similar to that of homoserine . The methylated fatty acid fraction of compound X was subjected to gas-liquid chromatography and revealed methyl palmitate and methyl stearate in a 4.6:1 molar ratio . The structure of compound X was further analyzed by combining mass spectrometry, 31P-NMR and 1H-NMR . The positive and negative fast atom bombardment spectra showed a major component of M(r) 1048 and a minor component of M(r) 1076 . Two different phosphate groups were identified in each of the components by 31P-NMR . Fast atom bombardment, tandem mass spectrometry, negative and positive chemical ionization mass spectrometry together with mass spectra analyses of the water-soluble and ether-soluble products obtained by methanolysis has shown that, in addition to palmitic and stearic acid residues, the presence of glycerol, ribitol, cholinephosphate and homoserinephosphate residues . It is suggested that the apparent structure of compound X is either a phosphatidylcholine attached via a phosphotriester bond to a ribitolphosphohomoserine moiety or a phosphatidylhomoserine attached via a phosphotriester bond to a ribitolphosphocholine moiety . The major molecular species is the dipalmitoylderivative (M(r) 1048), whereas the minor molecular species is a stearoyl palmitoyl derivative (M(r) 1076).

Eur J Biochem, 1995 Feb 1, 227(3), 745 - 52
Relationship of subunit 8 of yeast ATP synthase and the inner mitochondrial membrane . Subunit 8 variants containing multiple lysine residues in the central hydrophobic domain retain function; Papakonstantinou T et al.; A molecular genetic approach has been used to test the proposition that the central hydrophobic domain of yeast mitochondrial ATP synthase subunit 8 represents a transmembrane stem in contact with the lipid bilayer . The rationale for this approach is the general inability of membrane bilayers to accomodate unshielded charged residues of polypeptide chains . Non-polar residues at several positions within the central hydrophobic domain of subunit 8 were replaced with the positively charged amino acid lysine . This was done in an attempt to disrupt subunit 8 function, and thereby determine the boundaries of the putative transmembrane stem . Each subunit 8 variant was allotopically expressed in vivo as a mitochondrial import precursor encoded by a nuclear gene . It was found that all variants, which included proteins carrying two lysines at various positions in the hydrophobic domain, exhibited the ability to restore growth of subunit-8-deficient cells on the non-fermentable substrate ethanol . This indicated that the function of none of these subunit 8 variants was severely compromised . There was also no detectable change in the proteolipid characteristics of subunit 8, as defined by the chloroform/methanol solubility properties of variant proteins extracted from membranes following import into isolated mitochondria . These data suggest that subunit 8 is located in a hydrophobic niche in the mitochondrial ATP synthase, probably in contact with other protein subunits of the complex . We conclude that the function of subunit 8 does not necessarily require it to be integrated within the inner mitochondrial membrane, in contact with the lipid bilayer . Our findings also suggest that hydropathy plots, indicating hydrophobic domains within polypeptides, cannot reliably be interpreted as transmembrane helices in the absence of independent evidence.

J Surg Res, 1995 Feb, 58(2), 240 - 6
Pectin improves colonic function in rat short bowel syndrome; Roth JA et al.; Short bowel syndrome is characterized by weight loss, diarrhea, and malabsorption . Pectin, a highly fermentable fiber, improves small and large bowel mucosal structure, prolongs intestinal transit, and decreases diarrhea . This study determined if the addition of citrus pectin to an enteral liquid diet (LD) improved structure and absorptive function in the rat jejunum and colon following massive intestinal resection . Twenty-one male Sprague-Dawley rats underwent placement of gastrostomy tube for isocaloric, isonitrogenous feeding and either 60% small bowel and cecal resection or small bowel transection with anastomosis . Animals in each group were then randomly and equally assigned to receive either LD (Enercal Plus, Wyeth) or LD supplemented with 2% citrus pectin for 7 days . Study variables included body weight change, percentage of stool solidity, jejunal villous height (JVH) and crypt depth, colonic crypt depth (CCD), and colonic short-chain fatty acid content (SCFA) . Jejunal {14C}glucose absorption and colonic {3H}H2O absorption were measured by a dual in vivo perfusion assay . Resection significantly (P < 0.05) decreased body weight, stool solidity, and colonic SCFA content; enlarged structure (JVH, CCD); and increased absorptive function in the remaining bowel . Pectin significantly decreased (P < 0.05) body weight loss, increased (P < 0.05) stool solidity, and improved (P = 0.05) colonic water absorption following resection without significantly altering mucosal structure . It is concluded that pectin improves colonic absorptive function following massive bowel resection in the rat.

J Nutr, 1995 Feb, 125(2), 283 - 92
Feeding Australian Acacia gums and gum arabic leads to non-starch polysaccharide accumulation in the cecum of rats; Annison G et al.; Exudative gums from two Australian Acacia species (A . pycnantha and A . baileyana) and gum arabic (from A . senegal) were fed to rats at graded levels (0, 20, 40, 80 g/kg), replacing cellulose in purified diets containing cholesterol plus cholic acid . Compared with consumption of the control diet containing cellulose only, consumption of the gums had no significant effects on concentrations of plasma or liver cholesterol . Plasma triacylglycerol concentrations were higher in rats fed gum arabic, whereas liver triacylglycerols were lower in rats fed the gums . The gums did not affect the total pool of volatile fatty acids in the ceca, as compared with results in controls, but did promote the relative contribution of propionate at the expense of acetate . In rats fed the diet containing cellulose (80 g/kg) the proportions of cecal acetate:propionate:butyrate were 76:15:9, whereas in the rats fed A . pycnantha gum, gum arabic and A . baileyana gum (80 g/kg) the ratios were 42:54: 4, 35:46:19 and 43:53:4, respectively . The low apparent fermentability of the gums was confirmed by the accumulation of non-starch polysaccharides in cecal digesta . In rats fed 80 g/kg A . pycnantha gum, 3.44 g of soluble non-starch polysaccharides was measured in the ceca, which was 58% of the dry weight of the cecal contents . We conclude that the biological activities of the Australian Acacia gums were similar to those of gum arabic and that these gums may have potential value as human food ingredients.

J Nutr, 1995 Feb, 125(2), 155 - 63
Eijkman's contribution to the discovery of vitamins; Carpenter KJ et al.; The work by Christiaan Eijkman in Batavia (now Djakarta, the capital of Indonesia) between 1890 and 1900, for which he received a Nobel Prize, is reviewed . While searching for a microorganism responsible for beriberi, he found that a condition of polyneuritis, with similarities to beriberi, could be produced consistently in chickens by feeding them polished rice, and that addition of the silverskin removed during polishing prevented this . He showed further that the silverskin did not act by physically preventing the entry of microorganisms into the endosperm, nor was its action explained by the protein and salts that it contributed . His tentative hypothesis was that this fraction contributed an antidote to a nerve poison produced by the fermentation of starch in the chickens' crop . However, his successor continued to use Eijkman's animal model and was able to show that silverskin supplied some unknown factor(s) that was required regardless of whether or not the diet contained starch . Fractionation eventually showed thiamin to be the active factor.

J Am Diet Assoc, 1995 Feb, 95(2), 190 - 4
Survey of dental nutrition knowledge of WIC nutritionists and public health dental hygienists; Faine MP et al.; OBJECTIVE: To assess two groups' knowledge of the role of diet in the etiology of dental caries: nutritionists in the Special Supplemental Food Program for Women, Infants, and Children (WIC) and public health dental hygienists . DESIGN: A self-administered survey contained questions about the cause of dental caries, the importance of caries-preventive measures, dietary factors linked to dental caries, dietary advice for patients with active dental caries, and diet-related topics discussed with clients . SUBJECTS: Surveys were sent to all WIC nutritionists and public health dental hygienists in Washington, Oregon, and Idaho . Of the 235 surveys mailed, 188 completed surveys composed the final sample . STATISTICAL ANALYSES PERFORMED: Descriptive tests, means and frequencies, and the chi 2 test were used to measure differences in nutritionists' and hygienists' responses . RESULTS: One half of the nutritionists and three fourths of the hygienists recognized that dental caries was caused by a bacterial infection . Most dental researchers consider fluoride exposure and dental sealants to be highly effective caries-preventive measures; in contrast, WIC nutritionists and dental hygienists identified oral hygiene as being most important in preventing caries . Frequency of snacking and retentiveness of food in the mouth were accurately rated important dietary factors in the development of dental caries by both groups . However, limiting intake of fermentable carbohydrates between meals was not considered the most important dietary advice for clients . APPLICATIONS: Results suggest that current research about the role of diet in the prevention of dental caries should be included in both nutrition and dental hygiene curriculums and continuing education courses for these professionals.

Proc Soc Exp Biol Med, 1995 Feb, 208(2), 150 - 8
Recombinant hemoglobins as blood substitutes: a biotechnology perspective; Kumar R; Human hemoglobin can be produced in microbial and mammalian organisms using many different expression systems . It is anticipated that recombinant hemoglobins (or globin genes) will have many applications including as an infectious agent-free, inexpensive raw material for a red blood cell substitute, as a vehicle for expression or delivery of other biomolecules, and in gene therapy of inherited hemoglobinopathies . Recombinant expression, combined with site-directed mutagenesis, is facilitating the modification of the functional properties of hemoglobin . Although a functional hemoglobin molecule can be derived using many of the known expression systems, the choice of the production system for manufacturing depends on the scale, acceptable cost, and the associated environmental impact of the various processes . While the efficient bacterial production systems yield a modified, "surrogate" hemoglobin, the transgenic animal-derived product is virtually identical to the human erythrocyte-derived hemoglobin . Both the microbial fermentation, and the mammalian transgenic systems can be geared to produce the enormous quantities of hemoglobin expected to be required to meet the anticipated demand for a successful blood substitute in the future.

J R Soc Med, 1995 Feb, 88(2), 63 - 6
Gut permeability measured by polyethylene glycol absorption in abnormal gut fermentation as compared with food intolerance; Eaton KK et al.; Gut permeability has been studied in patients with either food intolerance or abnormal gut fermentation as well as in normal subjects . Permeability was measured by polyethylene glycol absorption, and the reasons for this choice of probe are discussed . Results show that both symptomatic groups have statistically very highly significant deviations from the normal (P < 0.01), consisting of over-adsorption, significant at molecular weights 242, 286, 330 and 374 . Whilst both study groups were different from the normal they were not different from each other . The implications for these findings in the diagnosis and management of food intolerance and abnormal gut fermentation are discussed.

Protein Expr Purif, 1995 Feb, 6(1), 72 - 8
Large-scale production of a soluble human beta-1,4-galactosyltransferase using a Saccharomyces cerevisiae expression system; Herrmann GF et al.; We report in this communication the first large-scale heterologous expression of a glycosyltransferase in yeast . A soluble form of a human beta-1,4-galactosyltransferase (EC 2.4.1.38) was expressed using a Saccharomyces cerevisiae expression system . Fermentation technology afforded the means to increase the expression level of the beta-1,4-galactosyltransferase up to a concentration of 700 mU/liter . The enzyme was produced at a scale of 200 units . The recombinant soluble enzyme was purified 766-fold to a specific activity of approx . 2 U/mg using a purification protocol based on sequential affinity chromatography on N-acetylglucosaminyl- and alpha-lactalbumin-Sepharose, respectively . This study demonstrates that heterologous expression of a glycosyltransferase is possible on a large scale and offers an alternative to natural sources like human breast milk or bovine colostrum.

J Dairy Sci, 1995 Feb, 78(2), 342 - 52
Ruminal fermentation and digestion in lactating cows fed grass silage with protein and energy supplements; Petit HV et al.; Four multiparous Holstein cows were used in a 4 x 5 incomplete Latin square design to study the effects of different dietary sources of energy and protein on digestion, ruminal fermentation, and degradability in cows fed high moisture grass silage . The five treatments were an all silage diet (control); silage and concentrate containing soybean meal fed with corn, beet pulp, or a mixture (50:50 on a DM basis) of oats and barley; and fish meal fed with beet pulp . Concentrates were fed between .70 and .76% of BW to give similar CP and NEL intakes . Total DMI and milk production were lower for unsupplemented than for supplemented cows, but digestion and ruminal fermentation did not differ . Digestibility of fiber and concentration of total VFA were higher for cows fed corn than for those fed the mixture of oats and barley, but starch source had no effect on total DMI or milk production and composition . Energy source had no effect on total DMI or milk production and composition . Digestibility of DM and NDF was higher, and ruminal concentration of NH3 N and degradability of silage N tended to be lower, for cows fed beet pulp than for those fed starch, suggesting an improvement in the microbial protein synthesis in the rumen when beet pulp was fed instead of starch.

Diabet Med, 1995 Feb, 12(2), 164 - 72
One-year acarbose treatment raises fasting serum acetate in diabetic patients; Wolever TM et al.; alpha-Glucosidase inhibitors such as acarbose improve blood glucose control in diabetes by delaying or reducing carbohydrate absorption . The fermentation of malabsorbed carbohydrate in the colon is associated with the production of gas, leading to flatulence, and short chain fatty acids such as acetate, which may have systemic effects . To see if acarbose raised fasting serum acetate in diabetic patients, we studied 85 subjects selected from the 267 who had completed a 1-year, double-blind, placebo-controlled, parallel design study of the effects of acarbose in the treatment of diabetes . At baseline, there was no significant difference between the 44 subjects subsequently randomized to placebo and the 41 randomized to acarbose, respectively, in fasting serum acetate (80 +/- 5 vs 71 +/- 4 mumoll-1) or glycosylated haemoglobin (HbA1C; 7.2 +/- 0.3 vs 7.4 +/- 0.3%) . Compared to placebo, acarbose treatment significantly increased fasting serum acetate by 11 +/- 4 vs 2 +/- 3 mumoll-1 (p < 0.02) and reduced HbA1C by -0.59 +/- 0.16 vs -0.13 +/- 0.20% (p < 0.02) . Acarbose treatment had no significant effect on serum cholesterol or non-esterified fatty acids, but was associated with a significant increase in flatulence . There was no relationship between changes in serum acetate and changes in HbA1C, serum cholesterol or symptoms . We conclude, in subjects with diabetes who tolerate therapy for a 1-year period, that acarbose treatment increases serum acetate . The magnitude of change in acetate was unrelated to side-effects or changes in blood glucose control or serum lipids.

Br J Nutr, 1995 Feb, 73(2), 241 - 51
Effects of dietary propionate on hepatic glucose production, whole-body glucose utilization, carbohydrate and lipid metabolism in normal rats; Boillot J et al.; Increased intake of dietary fibres is associated with several beneficial effects on carbohydrate and lipid metabolism . The colonic fermentation of dietary fibres produces short-chain fatty acids (SCFA; acetate, propionate and butyrate) . Some authors have suggested that SCFA could be partly responsible for the effects of dietary fibres . The purpose of the present study was to test the effects of one of the SCFA, propionate . The effects of moderate amounts of dietary propionate on insulin sensitivity and hepatic glucose production were studied in male Sprague-Dawley rats . Two groups of twenty-one adult rats were fed for 3 weeks on a diet containing 78 g propionate/kg (P) or 78 g/kg of a poorly fermentable cellulose (control group; C) . Feed intake, body weight, fasting plasma glucose, insulin, free fatty acids, alanine, lactate, glycerol and beta-hydroxybutyrate levels were measured weekly in anaesthetized rats . At the end of the feeding period basal hepatic glucose production (BHGP) was measured with a primed continuous infusion of {3-3H}glucose and the in vivo insulin sensitivity in rats was quantified by the euglycaemic-hyperinsulinaemic clamp technique (0.6 and 2 U/kg per h) . At that time fasting plasma glucose measured in anaesthetized rats was significantly lower in group P than in group C: 7.7 (SE 0.2) v . 8.5 (SE 0.2) mmol/l respectively (P < 0.002); plasma insulin levels were not significantly different . Neither the BHGP (mg/min per kg; C 14.8 (SE 1.3), P 15.1 (SE 1.3); n 7, not significant) nor the basal metabolic clearance (ml/min per kg; 8.9 (SE 0.8) v . 9.9 (SE 1.1); not significant) were different between treatments . Hepatic glucose production and glucose utilization at the two insulin concentrations (approximately 500 and 1500 mU/l respectively, n 7) did not differ significantly between the two groups . These results show that dietary propionate chronically ingested by normal rats could decrease fasting glycaemia, but from our findings, no effect on hepatic glucose production and whole-body glucose utilization could be clearly demonstrated.

Int J Food Sci Nutr, 1995 Feb, 46(1), 13 - 6
Reduction of cyanide levels in cassava during sequential sundrying and solid state fermentation; Zvauya R et al.; The cyanide levels were followed during protein enrichment of cassava by the fungus Aspergilus oryzae . The total cyanogen level decreased by 158 mg/kg dry weight to 54.2 mg/kg dry weight as a result of the whole process including fermentation . The cyanogenic glucoside level decreased by 88% during the fermentation process while acetone cyanohydrin was retained in the cassava . The prefermentation processing which involved crushing, sundrying and milling the cassava into flour, reduced the total cyanogen levels by 40% . The process resulted in considerable reduction in the cyanogenic content of the product.

Vet Hum Toxicol, 1995 Feb, 37(1), 55 - 9
Fusarium proliferatum-fermented corn stimulates development of placental glutathione S-transferase-positive altered hepatic foci in female rats; Lebepe-Mazur S et al.; Groups of 8 6-w-old female Sprague-Dawley rats were initiated with 30 mg diethylnitrosamine (DEN)/kg . Control and initiated groups were fed a semipurified diet or diets supplemented with Fusarium proliferatum-contaminated corn to contain 20 or 50 mg fumonisin B1 (FB1)/kg . Histochemical staining for gamma-glutamyltransferase (GGT) and immunochemical staining for placental glutathione S-transferase (PGST), markers of altered hepatic foci (AHF), were performed on serial frozen hepatic sections . Gamma-glutamyltransferase -(+) AHF were not found in any group . Dosing with DEN significantly increased the number of PGST-(+) hepatocytes compared to the uninitiated groups . Groups fed F proliferatum-containing diets also had a significantly increased number of PGST-(+) AHF compared with those fed no F proliferatum . The volume percentage of liver occupied by PGST-(+) foci was significantly greater in the groups treated with DEN or F proliferatum . The number of PGST-(+) AHF/liver in the groups given DEN was also significantly greater than in the uninitiated groups . Fusarium proliferatum exposure also significantly increased the number of PGST-(+) AHF/liver . Feeding F proliferatum containing 20 mg FB1/kg promoted the development of DEN-initiated AHF in rats . Placental glutathione S-transferase was a more useful marker than GGT in detecting AHF produced by small amounts of F proliferatum mycotoxins fed after initiating dosing with DEN.

J Antibiot (Tokyo), 1995 Feb, 48(2), 99 - 102
Mer-A2026A and B, novel piericidins with vasodilating effect . I . Producing organism, fermentation, isolation and biological properties; Kominato K et al.; A strain of Streptomyces was found to produce new piericidins . The compounds were purified and separated into two substances named Mer-A2026A and B . These new piericidins exhibited vasodilating and depressor activities.

J Antibiot (Tokyo), 1995 Feb, 48(2), 169 - 74
Biological and pharmacological properties of highly selective new endothelin converting enzyme inhibitor WS79089B isolated from Streptosporangium roseum No . 79089; Tsurumi Y et al.; WS79089B a highly specific endothelin converting enzyme (ECE) inhibitor has been isolated from the fermentation broth of Streptosporangium roseum No . 79089 . WS79089B showed highly selective ECE inhibition activity with IC50 value of 0.14 microM and behaved as a competitive inhibitor of ECE, with Ki values of 8.9 x 10(-8) M . The sodium salt of WS79089B (FR901533) inhibited big endothelin-1 (big ET-1) induced pressor effect in a dose dependent manner when administered to male Sprague-Dawley rats intravenously dosed 2 minutes prior to big ET-1 challenge.

J Antibiot (Tokyo), 1995 Feb, 48(2), 106 - 12
Isolation and biological activity of thielocins: novel phospholipase A2 inhibitors produced by Thielavia terricola RF-143; Matsumoto K et al.; Thielocins A2 alpha, A2 beta, A3, B1, B2 and B3 were isolated as a novel family of phospholipase A2 inhibitors from the fermentation broth of Thielavia terricola RF-143 together with thielavins and thielocins A1 alpha and A1 beta . The most potent inhibitory activity (IC50 = 0.0033 microM) against rat group II phospholipase A2 was shown by thielocin A1 beta . Against human group II phospholipase A2, thielocin B3 (IC50 = 0.076 microM) was the most potent.

Res Microbiol, 1995 Feb, 146(2), 129 - 41
Involvement of a single periplasmic hydrogenase for both hydrogen uptake and production in some Desulfovibrio species; Hatchikian EC et al.; Various sulphate-reducing bacteria differing in the number of genes encoding hydrogenase were shown to ferment lactate in coculture with Methanospirillum hungatei, in the absence of sulphate . The efficiency of interspecies H2 transfer carried out by these species of sulphate-reducing bacteria does not appear to correlate with the distribution of genes coding for hydrogenase . Desulfovibrio vulgaris Groningen, which possesses only the gene for {NiFe} hydrogenase, oxidizes hydrogen in the presence of sulphate and produces some hydrogen during fermentation of pyruvate without electron acceptor . The hydrogenase of D . vulgaris was purified and characterized . It exhibits a molecular mass of 87 kDa and is composed of two different subunits (60 and 28 kDa) . D . vulgaris hydrogenase contains 10.6 iron atoms, 0.9 nickel atom and 12 acid-labile sulphur atoms/molecule, and the absorption spectrum of the enzyme is characteristic of an iron-sulphur protein . Maximal H2 uptake and H2 evolution activities were 332 and 230 units/mg protein, respectively . D . vulgaris cells contain exclusively the {NiFe} hydrogenase, whatever the growth conditions, as shown by biochemical and immunological studies . Immunocytolocalization in ultrathin frozen sections of cells grown on lactate and sulphate, on H2 and sulphate and on pyruvate showed that the {NiFe} hydrogenase was located in the periplasmic space . Labelling was enhanced in cells grown on H2 and sulphate and on pyruvate . The results enable us to conclude that D . vulgaris Groningen contains a single hydrogenase of the {NiFe} type, located in the periplasmic space like that described for D . gigas . This enzyme appears to be involved in both H2 uptake and H2 production, depending on the growth conditions.

J Nutr Sci Vitaminol (Tokyo), 1995 Feb, 41(1), 95 - 104
Effect of galactooligosaccharides on calcium absorption in rats; Chonan O et al.; The effect of transgalactosylated oligosaccharides (TOS), which are oligosaccharides that are unhydrolyzed in the small intestine and are fermented by the intestinal bacteria, on calcium absorption was examined in male Wistar rats for 10 days . The apparent calcium absorption ratios and the apparent retention ratios were significantly higher in the rats fed TOS-containing diets (5 or 10 g/100 g of diet) . In the second experiment, the cecum was ligated in situ and calcium absorption from the cecum was observed after injecting TOS into the cecal lumen . Four hours after the injection, the calcium concentration in the cecal vein of the rats given TOS was significantly higher than that of the control . The calcium content in the liquid phase of the cecal lumen and the liquid phase weight were also increased by the injection of TOS into the cecum . Although the extent of calcium absorption from the cecum of rats fed TOS is due to overall calcium absorption is not known, under the experimental conditions used in the present study the stimulatory effect of TOS on calcium absorption may be partly associated with increased solubility of calcium and the fluid content in the intestinal lumen.

Dtsch Tierarztl Wochenschr, 1995 Feb, 102(2), 96 - 101
{Dermatophilus congolensis infection in Brandenburg}; Kohler B et al.; At first time Dermatophilus (D.) congolensis-infection was diagnosed in Brandenburg in 3 sheep herds and in one horse, which had contact to diseased sheep . The causative agent was introduced from West-Germany probably . Cause of the disease was influenced by a longer rain period and by secondary infections through Staph . aureus var . ovis . The morbidity came up to 90%, the mortality of lambs was 10% . Clinical picture, diagnostic and control of the disease are described . Economical losses are caused by disturbances of the development and deaths of animals mainly . Treatment of sheep was successful with Terramycin LA or 200 mg Oxytetracycline by i.m . injection of 1 ml within 7 days . All isolated strains of D . congolensis caused beta-hemolysis and liquidation of Loffler-Medium (heated denatured serum of cattle), and gelatin and fermented glucose and fructose to acid.

Appl Environ Microbiol, 1995 Feb, 61(2), 718 - 28
Mechanisms of yeast flocculation: comparison of top- and bottom-fermenting strains; Dengis PB et al.; The flocculation of two brewing yeast strains, top-fermenting strain Saccharomyces cerevisiae MUCL 38485 and bottom-fermenting strain Saccharomyces carlsbergensis MUCL 28285, has been investigated by means of a turbidimetric test . The two strains showed different electrical properties, a different hydrophobicity, and a different surface chemical composition . They flocculated according to completely different mechanisms; however, no correlation between the cell physicochemical properties and the onset of flocculation was found for either strain . Flocculation of the bottom strain was governed by a lectin-mediated mechanism . It was inhibited by mannose and some other sugars, required calcium specifically, occurred in a narrow pH range different from the isoelectric point, and was not influenced by ethanol . The onset of flocculation at the end of the exponential phase was controlled both by the appearance of "active" lectins at the cell surface and by the decrease in sugar concentration in the solution . Flocculation of the top strain was not inhibited by mannose, did not require the addition of calcium, and took place at the cell isoelectric point . Low concentrations of ethanol broadened the pH range in which the cells flocculated, and flocculation was favored by an increase of ionic strength . Adsorbed ethanol may induce flocculation by reducing the electrostatic repulsion between cells, by decreasing steric stabilization, and/or by allowing the protrusion of polymer chains into the liquid phase . The onset of flocculation was controlled by both a change of the cell surface and an increase in ethanol concentration . The only evidence for an adhesin-mediated mechanism was the specific requirement for a small amount of calcium.

Appl Environ Microbiol, 1995 Feb, 61(2), 518 - 25
Cloning and characterization of a gene encoding a cell-bound, extracellular beta-glucosidase in the yeast Candida wickerhamii; Skory CD et al.; The ability of yeasts to ferment cellodextrins is rare . Candida wickerhamii is able to use these sugars for alcohol production because of a cell-bound, extracellular, beta-glucosidase that is unusual by not being inhibited by glucose . A cDNA expression library in lambda phage was prepared with mRNA isolated from cellobiose-grown C . wickerhamii . Immunological screening of the library with polyclonal antibodies against purified C . wickerhamii cell-bound, extracellular beta-glucosidase yielded 12 positive clones . Restriction endonuclease analysis and sequence data revealed that the clones could be divided into two groups, bglA and bglB, which were shown to be genetically distinct by Southern hybridization analyses . Efforts were directed at the study of bglB since it appeared to code for the cell-bound beta-glucosidase . Sequence data from both cDNA and genomic clones showed the absence of introns in bglB . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of cell lysates from Escherichia coli bglB clones confirmed the presence of an expressed protein with an apparent molecular mass of 72 kDa, which is consistent with that expected for an unglycosylated form of the enzyme . Amino acid comparisons of BglB with other beta-glucosidase sequences suggest that it is a member of family 1 glycosyl hydrolases but is unusual in that it contains an additional 100 to 130 amino acids at the N terminus . This sequence did not have homologies to other known protein sequences and may impart unique properties to this beta-glucosidase.

Appl Environ Microbiol, 1995 Feb, 61(2), 413 - 20
Cloning and nucleotide sequencing of the membrane-bound L-sorbosone dehydrogenase gene of Acetobacter liquefaciens IFO 12258 and its expression in Gluconobacter oxydans; Shinjoh M et al.; Cloning and expression of the gene encoding Acetobacter liquefaciens IFO 12258 membrane-bound L-sorbosone dehydrogenase (SNDH) were studied . A genomic library of A . liquefaciens IFO 12258 was constructed with the mobilizable cosmid vector pVK102 (mob+) in Escherichia coli S17-1 (Tra+) . The library was transferred by conjugal mating into Gluconobacter oxydans OX4, a mutant of G . oxydans IFO 3293 that accumulates L-sorbosone in the presence of L-sorbose . The transconjugants were screened for SNDH activity by performing a direct expression assay . One clone harboring plasmid p7A6 converted L-sorbosone to 2-keto-L-gulonic acid (2KGA) more rapidly than its host did and also converted L-sorbose to 2KGA with no accumulation of L-sorbosone . The insert (25 kb) of p7A6 was shortened to a 3.1-kb fragment, in which one open reading frame (1,347 bp) was found and was shown to encode a polypeptide with a molecular weight of 48,222 . The SNDH gene was introduced into the 2KGA-producing strain G . oxydans IFO 3293 and its derivatives, which contained membrane-bound L-sorbose dehydrogenase . The cloned SNDH was correctly located in the membrane of the host . The membrane fraction of the clone exhibited almost stoichiometric formation of 2KGA from L-sorbosone and L-sorbose . Resting cells of the clones produced 2KGA very efficiently from L-sorbosone and L-sorbose, but not from D-sorbitol; the conversion yield from L-sorbosone was improved from approximately 25 to 83%, whereas the yield from L-sorbose was increased from 68 to 81% . Under fermentation conditions, cloning did not obviously improve the yield of 2KGA from L-sorbose.

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