J Biotechnol, 1992 Jun, 24(1), 75 - 83 Fuzzy reasoning system for fault diagnosis of physiological activities in a cultivating process; Bustamante ZR et al.; Aiming at development of a system which supports cultivating operations, a method to diagnose physiological activities in a cultivating process is presented, and a fuzzy expert system for diagnosing Lactobacillus casei cultivating process is implemented in this paper . This system can calculate specific rates of cell growth, substrate consumption, and product formation with measuring cell mass concentration, substrate concentration, and product concentration by using a turbidity sensor and HPLC . A database is implemented, where standard curves on specific rates representing characteristics of microorganisms are stored according to normalized substrate consumption . Comparing the calculated specific rates with standard values derived from the database, the system diagnoses physiological activities of the microorganisms . As a case study, a knowledge base for diagnosing lactic acid production process is implemented . The use of fault diagnosis on pH malfunctions by the expert system proves its reasonable performance. J Infect Dis, 1992 Jun, 165(6), 1142 - 4 Hydrogen peroxide production by Lactobacillus species: correlation with susceptibility to the spermicidal compound nonoxynol-9; McGroarty JA et al.; Facultative anaerobic lactobacilli were recovered from the vaginas of 96.8% of 63 nonpregnant, healthy, premenopausal women . The predominant species were Lactobacillus jensenii, Lactobacillus acidophilus, and Lactobacillus casei . Of the women, 74.6% had hydrogen peroxide-producing lactobacilli, 22.2% had non-hydrogen peroxide-producing lactobacilli, and 3.2% had no lactobacilli . None of the 68 isolates had catalase activity . Some 68.2% of the isolates were inhibited by concentrations of less than or equal to 1% (wt/vol) of nonoxynol-9 (bactericidal for 73.3% of isolates, bacteriostatic for 26.7%) . The remaining 31.8% could grow in all concentrations to 25% (wt/vol) of nonoxynol-9 . All of the lactobacilli that were sensitive to nonoxynol-9 produced hydrogen peroxide whereas only 3 of 21 resistant strains were hydrogen peroxide producers . A significant correlation (P less than .001, chi 2 test) was found between hydrogen peroxide production and sensitivity to nonoxynol-9 . It is suggested that the vaginal flora of spermicide users could be depleted of hydrogen peroxide-producing lactobacilli, possibly increasing susceptibility to urogenital infection. Protein Sci, 1992 Jun, 1(6), 796 - 800 Reversible dissociation and unfolding of the dimeric protein thymidylate synthase; Perry KM et al.; Conditions for in vitro unfolding and refolding of dimeric thymidylate synthase from Lactobacillus casei were found . Ultraviolet difference and circular dichroism spectra showed that the enzyme was completely unfolded at concentrations of urea over 5.5 M . As measured by restoration of enzyme activity, refolding was accomplished when 0.5 M potassium chloride was included in the refolding mixture . Recombination of subunits from catalytically inactive mutant homodimers to form an active hybrid dimer was achieved under these unfolding-refolding conditions, demonstrating a monomer to dimer association step. FEMS Microbiol Lett, 1992 May 15, 72(1), 97 - 102 Lantibiotic-mediated anti-lactobacillus activity of a vaginal Staphylococcus aureus isolate; Scott JC et al.; Staphylococcus aureus strain 26 inhibited the growth of 23 of 26 lactobacilli of endocervical origin, but only two of 17 staphylococci, in deferred antagonism tests . The inhibitory agent, a bacteriocin-like inhibitory substance (BLIS) named staphylococcin Au-26, was obtained from vigorously shaken liquid cultures containing a 0.1% (v/v) supplement of Tween 80 and was purified by chromatographic fractionation on XAD-2, carboxymethyl Sephadex and reversed phase HPLC . The molecular mass of staphylococcin Au-26 was estimated by SDS-PAGE to be approx . 2700 . The detection of lanthionine residues in the molecule, the high stability to heating at acidic but not alkaline pH values and inactivation by proteinases indicate that staphylococcin Au-26 is a member of the lantibiotic class of peptide antibiotics--the first reported to be produced by a S . aureus strain . Primary sequence analysis showed that the N-terminus of the molecule is isoleucine, a characteristic also displayed by the lantibiotics nisin, epidermin and gallidermin. J Gen Microbiol, 1992 May, 138 ( Pt 5), 849 - 59 D-alanyl-lipoteichoic acid in Lactobacillus casei: secretion of vesicles in response to benzylpenicillin; Pollack JH et al.; Vesicles containing lipoteichoic acid (LTA) have been isolated from Lactobacillus casei ATCC 7469 grown in the presence of either benzylpenicillin or D-cycloserine . These cell wall antibiotics enhanced the rate of LTA and lipid secretion 6.7 times, whereas chloramphenicol inhibited their release . The formation of these vesicles from peripheral and septal wall regions did not appear to be the result of bacteriolysis . The vesicle composition of LTA and lipid was similar to that of the cytoplasmic membrane whereas the protein composition was dissimilar . The size of these vesicles ranged from 20 to 40 nm and the length of LTA ranged from 5 to 50 glycerol phosphate residues . The isolation of these vesicles provides a potential in vitro acceptor system for studying the D-alanylation of lipoteichoic acid. Hum Reprod, 1992 May, 7(5), 612 - 20 Microbial colonization and sperm--mucus interaction: results in 1000 infertile couples; Eggert-Kruse W et al.; After screening a large series of infertile patients (n = 1000 couples), potentially pathogenic microorganisms were identified in genital secretions of the majority of couples . None of the patients displayed signs or symptoms of infection of the lower genital tract . In semen specimens and cervical swabs, mycoplasmas were found in 18 and 12%, potentially pathogenic aerobic bacteria in 50 and 31%, additionally commensal aerobes in 38% and 25%, respectively . The microbial pattern showed great variability with polymicrobial growth most common . The rate of cultures positive for potentially pathogenic anaerobes was markedly influenced by the transport conditions . In endocervical material, Herpes simplex virus (HSV) was identified in 4.5% . Yeasts were found in the posterior vaginal fornix in 10% . Concerning both partners, there were only 10 couples (1%) from whom microorganisms in genital secretions could not be isolated, not including lactobacilli in females . This high prevalence of microbes and the low number of leukocytes indicate colonization rather than infection . When the microbial findings from both partners were analysed with regard to the outcome of sperm-cervical mucus penetration testing in vitro, which was performed simultaneously, no significant correlation was found . Furthermore, microbial prevalence did not differ between couples with 'explained' and 'unexplained' infertility . The results of this study demonstrate that in patients without symptoms of genital tract infection, microbial colonization is of minor importance for sperm--mucus interaction and that extensive microbial screening should be preferentially performed in cases of poor sperm and/or mucus function. Appl Environ Microbiol, 1992 May, 58(5), 1549 - 53 Comparison of contact angles and adhesion to hexadecane of urogenital, dairy, and poultry lactobacilli: effect of serial culture passages; Reid G et al.; The aim of this study was to examine the hydrophobicities of 23 urogenital, dairy, poultry, and American Type Culture Collection isolates of lactobacilli and to determine the effect on hydrophobicity of serially passaging the strains in liquid medium . To this end, strains were grown after isolation and identification and then serially passaged up to 20 times . Hydrophobicity was assessed through contact angle measurements on lawns of cells by using water, formamide, methylene iodide, 1-bromonaphthalene, and hexadecane as wetting agents and through measurement of their partitioning in a hexadecane-water system . The hydrophobicities of these strains varied widely, with Lactobacillus casei strains being predominantly hydrophilic and L . acidophilus strains being mostly hydrophobic . For some isolates, serial passaging was accompanied by a clear loss of hydrophobic surface properties, whereas for other strains, cultures became heterogeneous in that some cells had already lost their hydrophobic surface properties while others were still hydrophobic . Adhesion of this collection of lactobacilli to hexadecane droplets in microbial adhesion to hexadecane (MATH) tests was driven by their aversion to water rather than by their affinity for hexadecane, as concluded from the fact that hexadecane contact angles were zero for all strains . Furthermore, adhesion of the lactobacilli to hexadecane in MATH tests occurred only when the water contact angle on the cells was above 60 degrees. Appl Environ Microbiol, 1992 May, 58(5), 1484 - 9 Novel paired starter culture system for sauerkraut, consisting of a nisin-resistant Leuconostoc mesenteroides strain and a nisin-producing Lactococcus lactis strain; Harris LJ et al.; Nisin-resistant Leuconostoc mesenteroides NCK293 and nisin-producing Lactococcus lactis subsp . lactis NCK401 were evaluated separately and in combination for growth and nisin production in a model sauerkraut fermentation . Strains were genetically marked and selectively enumerated by using antibiotic-containing media . The growth and survival of L . mesenteroides were similar in the presence and absence of Lactococcus lactis subsp . lactis . The growth of Lactococcus lactis subsp . lactis was not inhibited, although the maximum cell density was reduced and the population decline was more pronounced in the presence of L . mesenteroides . Nisin was detected within 24 h, and levels were relatively constant over the 12-day test period . The maximum cell populations and nisin level achieved could be altered by changing the initial cell ratios of L . mesenteroides and lactococcus lactis subsp . lactis . Isogenic nisin-producing and nisin-negative Lactococcus lactis subsp . lactis derivatives were used in combination with nisin-resistant L . mesenteroides to demonstrate that nisin levels produced in mixed culture were sufficient to retard the onset of the growth of nisin-sensitive, homofermentative Lactobacillus plantarum ATCC 14917. Gene, 1992 May 1, 114(1), 127 - 32 Cloning and sequencing the Lactobacillus brevis gene encoding xylose isomerase; Bor YC et al.; The gene (xylA) coding for the Lactobacillus brevis xylose isomerase (Xi) has been isolated and its complete nucleotide sequence determined . L . brevis Xi was purified and the N-terminal sequence determined . All attempts to directly clone the intact xylA using a degenerative primer deduced from amino acids (aa) 10-14 were not successful . A fragment coding for the first 462 bp from the 5' end of xylA was isolated by PCR with two primers, one coding for aa M36 to W43 and the second coding for an aa sequence (WGGREG) conserved in a number of Xi's isolated from other bacteria . From the sequence of this fragment, two additional PCR primers were synthesized, which were used in an 'outward' reaction to clone a 546-bp fragment including a region upstream from the N terminus . Finally, the complete xylA gene was cloned in a 0.43-kb NlaIII-SalI fragment and a 1.9-kb SalI-EcoRI fragment . The 449-aa sequence for the L . brevis Xi shows homology with Xis isolated from other bacteria, especially within the primary catalytic domains of the enzyme. Pediatr Dent, 1992 May-Jun, 14(3), 184 - 8 Two-year longitudinal observations of salivary status and dental caries in children with insulin-dependent diabetes mellitus; Twetman S et al.; Salivary status and caries incidence were studied in 28 young, Type 1 diabetics from the onset of the disease and during a two-year period . Flow rate, buffer capacity, glucose content, total protein concentration and levels of mutans streptococci and lactobacilli were determined in stimulated whole saliva every third month . Dental caries was recorded at onset and then once a year . Forty-six per cent of the children developed caries during the observation period . Caries incidence was significantly higher (P less than 0.05) during the first year of diabetes, compared with the second . Caries-active children displayed significantly higher HbA1c levels (P less than 0.001), compared with caries-inactive diabetics . The number of salivary lactobacilli dropped significantly (P less than 0.05) during the first six months of the disease, while mutans streptococci levels remained unchanged during the study period . Salivary glucose concentration showed a considerable individual variation, but tended to be lower during the second year . The results suggest a possible relationship between Type 1 diabetes treatment and caries. Sex Transm Dis, 1992 May-Jun, 19(3), 146 - 8 Treatment of bacterial vaginosis with lactobacilli; Hallen A et al.; 60 women with bacterial vaginosis were entered into a double blind, placebo-controlled treatment trial with lyophilized Lactobacillus acidophilus . The lactobacilli used were producing H2O2 . Immediately after completion of treatment, 16 out of 28 women who were treated with lactobacilli had normal vaginal wet smear results, in comparison to none of the 29 women treated with placebo . All women harboured Bacteroides at inclusion . Bacteroides was eliminated from the vagina of 12 out of 16 healthy women after treatment . Only three of the women who received the Lactobacillus suppository were free of bacterial vaginosis after the subsequent menstruation. Nippon Saikingaku Zasshi, 1992 May, 47(3), 511 - 4 {An improved tetrazolium agar medium for testing sugar fermentation in lactobacilli}; Nagasaki H et al.; An improved tetrazolium agar medium for testing sugar fermentation in lactobacilli is described . Basal medium 86 was essentially a modified MRS broth with the omission of glucose . The standard formula was 30 micrograms/ml of 2,3,5-triphenyltetrazolium chloride, 2% sugar to be tested, and 2% agar in medium 86 . Plates were incubated anaerobically for 2 days at 37C or 5 days at 30C, depending on the strain . With three strains each of group II and III lactobacilli, colorless, fermentation-positive colonies were clearly differentiated from red, fermentation-negative colonies . For three strains of group I lactobacilli, this medium was not satisfactory because they grew poorly on it unless supplemented with a sugar. Plasmid, 1992 May, 27(3), 169 - 76 Mobilization and location of the genetic determinant of chloramphenicol resistance from Lactobacillus plantarum caTC2R; Ahn C et al.; The mobilization of a nonconjugative plasmid (pCaT) that mediates chloramphenicol resistance in Lactobacillus plantarum caTC2R was achieved by comobilization with the conjugative plasmid pAM beta 1 . The conjugation studies confirmed that the 8.5-kb pCaT in L . plantarum caTC2R contains the gene responsible for chloramphenicol resistance and that the plasmid has several unique restriction sites which make it useful for genetic studies in Carnobacterium spp . Cloning studies showed that the gene responsible for chloramphenicol resistance is located in the 2.6-kb EcoRV-SalI region of pCaT . This was confirmed by probing the 3.0-kb BglII fragment of pCaT with a biotin-labeled 1.6-kb BstEII-HpaII fragment from the streptococcal-derived plasmid pVA797(Cmr) . Expression of chloramphenicol resistance in Carnobacterium as well as in other Lactobacillus species was achieved by electrotransformation using donor DNA from pCaT. Indian J Med Res, 1992 May, 95, 144 - 7 Mycoplasma hominis in women with bacterial vaginosis; Deodhar LP et al.; An association between M . hominis and bacterial vaginosis (BV) was looked for in total 205 women characterized as having BV . Vaginal specimens from these patients were studied for the presence of amines, polymorphonuclear leukocytes, clue cells, and lactobacilli, and were also cultured to isolate Gardnerella vaginalis, M . hominis, Trichomonas vaginalis, Candida albicans and anaerobes . G . vaginalis was found to be the most common isolate from 132 cases (64.3%) . M . hominis was isolated from 90 cases (43.9%) . 62 per cent of M . hominis isolates were associated with G . vaginalis . 100 age matched control group revealed low prevalence of G . vaginalis and M . hominis whereas the difference in isolation rate of anaerobes was not significant . Anaerobes were found in association with M . hominis in 40 per cent cases . The treatment of these patients was decided after knowing the etiological agent. Int J Food Microbiol, 1992 May, 16(1), 51 - 62 The contamination of pork with spoilage bacteria during commercial dressing, chilling and cutting of pig carcasses; Gill CO et al.; Swab samples from the surfaces of carcasses and cuts were obtained at various stages of the dressing, chilling and cutting operations in three pig processing plants . The aerobic microflora obtained from those swabs were enumerated and characterized . The flora on the skins of carcasses exiting the scalding tanks were dominated by Gram-positive organisms, with numbers about 10(3)/cm2 . After dehairing, numbers were about 10(4)/cm2 with major fractions of Gram-negative organisms . Flora numbers and compositions were largely unaltered after the singeing operations, but lesser numbers were recovered after the carcasses were polished . Carcass dressing did not change the numbers on the skin . During the chilling of carcasses, the flora at two large plants altered little, but drying of the carcass surfaces at a smaller plant reduced the Gram-negative fraction of the flora . Numbers on serous and fat surfaces exposed during the dressing and cutting of carcasses were initially about 10(2)/cm2 . That number was approximately maintained on finished skinned cuts produced at the smaller plant, but further contamination with lactobacilli and Brochothrix thermosphacta occurred during cutting . At the larger plants, the flora on skinned cuts were similar to those on skins, although further contamination with B . thermosphacta occurred at one plant. In Vivo, 1992 May-Jun, 6(3), 247 - 53 Distribution of TNF endogenously induced by various immunopotentiators and Lactobacillus casei in mice; Sakagami H et al.; Intravenous administration of heat-killed Lactobacillus casei YIT 9018 (LC) elicited endogenous cytotoxic factor (CF) production in ICR mice, peaking in serum after 2 h and declining gradually to basal level at 23 h . The endogenous CF production was significantly enhanced by priming with high molecular-weight lignins and glucans, but not by phenylpropenoid precursors or partially hydrolyzed products of glucans . The extent of stimulation of CF production by these priming agents was positively related to that of tumor necrosis factor (TNF) production, as judged by enzyme-linked immunosorbent assay . Endogenously produced TNF was concentrated more in liver, lung and intestine, as well as in serum, than in other organs . Histochemical examination revealed a significant increase in the number and swelling of Kupffer cells and sinusoidal endothelium in the liver of the treated mice. Plasmid, 1992 May, 27(3), 200 - 6 Isolation and characterization of IS1165, an insertion sequence of Leuconostoc mesenteroides subsp . cremoris and other lactic acid bacteria; Johansen E et al.; We have cloned and characterized an insertion sequence from Leuconostoc mesenteroides subsp . cremoris strain DB1165 . This element, designated IS1165, is 1553 bp, has imperfect inverted repeat ends, contains an open reading frame of 1236 bp, and is not related to any previously described insertion sequence . The copy number of IS1165 varies from 4 to 13 in L . mesenteroides subsp . cremoris strains allowing genetic fingerprinting of strains based on location and number of bands on hybridization . IS1165 or closely related elements have been detected by hybridization in L . lactis, L . oenos, Pediococcus sp., Lactobacillus helveticus, and Lb . casei but not in Lactococcus. J Biol Chem, 1992 Apr 25, 267(12), 8499 - 513 Primary structure, physicochemical properties, and chemical modification of NAD(+)-dependent D-lactate dehydrogenase . Evidence for the presence of Arg-235, His-303, Tyr-101, and Trp-19 at or near the active site; Kochhar S et al.; The NAD(+)-dependent D-lactate dehydrogenase was purified to apparent homogeneity from Lactobacillus bulgaricus and its complete amino acid sequence determined . Two gaps in the polypeptide chain (10 residues) were filled by the deduced amino acid sequence of the polymerase chain reaction amplified D-lactate dehydrogenase gene sequence . The enzyme is a dimer of identical subunits (specific activity 2800 +/- 100 units/min at 25 degrees C) . Each subunit contains 332 amino acid residues; the calculated subunit M(r) being 36,831 . Isoelectric focusing showed at least four protein bands between pH 4.0 and 4.7; the subunit M(r) of each subform is 36,000 . The pH dependence of the kinetic parameters, Km, Vm, and kcat/Km, suggested an enzymic residue with a pKa value of about 7 to be involved in substrate binding as well as in the catalytic mechanism . Treatment of the enzyme with group-specific reagents 2,3-butanedione, diethylpyrocarbonate, tetranitromethane, or N-bromosuccinimide resulted in complete loss of enzyme activity . In each case, inactivation followed pseudo first-order kinetics . Inclusion of pyruvate and/or NADH reduced the inactivation rates manyfold, indicating the presence of arginine, histidine, tyrosine, and tryptophan residues at or near the active site . Spectral properties of chemically modified enzymes and analysis of kinetics of inactivation showed that the loss of enzyme activity was due to modification of a single arginine, histidine, tryptophan, or tyrosine residue . Peptide mapping in conjunction with peptide purification and amino acid sequence determination showed that Arg-235, His-303, Tyr-101, and Trp-19 were the sites of chemical modification . Arg-235 and His-303 are involved in the binding of 2-oxo acid substrate whereas other residues are involved in binding of the cofactor. J Mol Biol, 1992 Apr 20, 224(4), 1179 - 80 Purification and crystallization of Lactobacillus casei folylpolyglutamate synthetase expressed in Escherichia coli; Cody V et al.; Folylpolyglutamate synthetase (FPGS) from Lactobacillus casei has been crystallized with polyethylene glycol and acetate buffer at pH 5.0 . The enzyme was obtained from Escherichia coli strain SF4 harboring the L . casei FPGS chromosomal gene on a pEMBL vector (pGT3-8.1) . Crystals of the enzyme were obtained which diffract to 2.6 A resolution . The crystals are monoclinic, space group P2(1), with unit cell dimensions of a = 54.07 A, b = 45.83 A, c = 84.37 A and beta = 107.92 degrees . A unit cell contains one molecule of the 43,000 Da enzyme per asymmetric unit . A complete X-ray data set on the native crystals has been collected. Biochem Biophys Res Commun, 1992 Apr 15, 184(1), 60 - 6 Evolutionary relationship of NAD(+)-dependent D-lactate dehydrogenase: comparison of primary structure of 2-hydroxy acid dehydrogenases; Kochhar S et al.; A comparison of the primary structures of NAD(+)-dependent D-lactate dehydrogenase with L-lactate dehydrogenase and L-malate dehydrogenase failed to show any sequence similarity . However, D-2-hydroxyisocaproate dehydrogenase from Lactobacillus casei, glycerate dehydrogenase from cucumber, D-3-phosphoglycerate dehydrogenase and erythronate 4-phosphate dehydrogenase from Escherichia coli showed 38%, 24%, 24% and 22% amino acid identity, respectively . The profile analysis of the aligned sequences confirmed their relatedness . The hydropathy profiles of the aligned dehydrogenases were almost identical between residues 100-300 indicating largely preserved folding patterns of their polypeptide chains . The data suggest that L- and D-specific 2-hydroxy acid dehydrogenase genes evolved from two different ancestors and thus represent two different sets of enzyme families. Br Dent J, 1992 Apr 11, 172(7), 271 - 8 Oral microbiology: current concepts in the microbiology of dental caries and periodontal disease; Hardie JM; The microbial flora of the mouth is highly complex, containing a wide variety of bacterial species . The most common types of oral disease, dental caries and periodontal disease, are both related to dental plaque and seem to occur when the normal balance between the microorganisms and the host is disturbed in some way . Dental caries is usually associated with increased numbers of mutans streptococci and lactobacilli at the sites of disease; estimation of salivary levels of these organisms may be useful for assessing caries risk in patients and for monitoring their response to preventive measures . A large number of 'candidate pathogens' have been identified as potential aetiological agents in different types of periodontal disease, although the 'specific plaque hypothesis' may still be controversial . Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, together with the poorly understood spirochaetes, have most frequently been reported as significant periodontopathogens and a number of possible virulence factors have been described . Application of modern molecular techniques to the study of the microbiology of oral diseases should allow rapid further progress to be made and will lead, hopefully, to improved methods of diagnosis, risk assessment and treatment. J Vet Med Sci, 1992 Apr, 54(2), 261 - 7 Bacterial flora of the respiratory tracts in chickens with a particular reference to Lactobacillus species; Kawaguchi I et al.; The effects of three different types of breeding such as isolator, floor, and cage breedings on the bacterial flora of the respiratory tracts (nasal cavity, tongue, pharygolarynx, trachea and air sac) in chickens were determined . Total viable bacterial numbers on the nasal mucus of chickens in the isolator breeding as control group (Group A) aged of 14 days were 10(4.6)/g of autopsy specimen (wet weight), 10(5.7)/g of sample in the cage breeding (Group B) aged of 28 days, and 10(7.0)/g of sample in the floor breeding (Group C) aged of 28 days . Staphylococci and micrococci were predominant bacteria in the nasal cavities of all groups . Total viable numbers of tongue and pharygolarynx were from 10(5.4) to 10(6.5)/g of autopsy specimen . Lactobacilli were the predominant bacteria in pharyngolarynx of chickens . The incidence of staphylococci and micrococci in trachea was lower than those in the another regions . Staphylococci and micrococci dominated in the air sacs of two groups (B and C), but the number and incidence of lactobacilli in the air sacs of chickens were lower than those in the another respiratory tracts . The only clostridia isolation in the air sacs of Group A was observed . A total of 75 strains of Lactobacillus species was isoalted from all respiratory organs and intestine of chickens . These strains were divided into 19 groups . Lactobacillus salivearius subsp . salivarius was the predominant lactobacilli isolated from tongue and pharyngolarynx . Most of isolates from the chicken intestines were mainly identified as the L . acidophilus group and L . reuteri.(ABSTRACT TRUNCATED AT 250 WORDS) J Reprod Med, 1992 Apr, 37(4), 331 - 4 Incidence of bacteremia at dilation and curettage; Sacks PC et al.; The American Heart Association does not recommend prophylactic antibiotics for patients undergoing dilation and curettage (D & C) except in the case of septic abortion or the presence of prosthetic valves . This recommendation is based on a retrospective analysis of case reports of infectious complications of D & C . To date we are unaware of prospective studies that answer this question . At a community hospital we studied 20 patients undergoing D & C for noninfectious indications . Aerobic and anaerobic blood cultures were performed before and during the D & C . All baseline cultures were negative . In one patient we were able to isolate Lactobacillus after the D & C, thus finding a 5% incidence of bacteremia . That places D & C in the same risk category as other diagnostic procedures considered low risk in the pathogenesis of subacute bacterial endocarditis . Our study thus validated the recommendations made by the American Heart Association. J Clin Pathol, 1992 Apr, 45(4), 328 - 31 Radioimmunoassay that measures serum vitamin B12; O'Sullivan JJ et al.; AIMS: To develop a specific radioimmunoassay for the routine determination of serum vitamin B12 . METHODS: Antisera were raised in rabbits by immunisation with the monocarboxylic acid derivative of cyanocobalamin coupled to human serum albumin . Antibody titres and affinities were determined and the antiserum giving the highest binding affinity constant, Ka, was used to develop the assay protocol . Donkey-anti-rabbit gamma globulin-coated magnetisable particles were used to separate the bound from free vitamin B12 . The considerable cobalamin binding capacity of human serum was destroyed by autoclaving in acetate-cyanide buffer . Sixty samples were assayed by the radioimmunoassay (RIA) and the Lactobacillus leichmannii assay . Recovery and cross-reactivity experiments were performed . RESULTS: Final rabbit antibody titres varied from 1/20,000 to 1/188,000 . Scatchard plots did not correlate with the antibody titres . The Ka values varied from 2.6 to 6.7 x 10(10) litres/mol . For maximum sensitivity the highest Ka (titre 1/66,000) was chosen . A tracer concentration of 22 pmol/l, an antiserum dilution of 1/100,000, and a sample volume of 0.1 ml were used . At an antiserum dilution of 1 in 100,000 the cyanocobalamin binding of the rabbit serum was diluted out . The assay showed excellent correlation with the microbiological assay, with 100% recovery of added vitamin B12 . Levels of cross-reactivity for dicyanide cobinamide and hydroxocobalamin were 9.8 and 8.1%, respectively . CONCLUSIONS: The development of this immunoassay permits the measurement of serum vitamin B12 without important interference from cobalamin analogues, related corrinoids, and non-specific binders. Scand J Dent Res, 1992 Apr, 100(2), 93 - 7 Effects of Weight Watchers' diet on salivary secretion rate, buffer effect and numbers of mutans streptococci and lactobacilli; Andreen I et al.; The aim of this investigation was to study how a change to the dietary regimen of the Weight Watchers' (WW) affected salivary secretion rate, buffer effect and number of cariogenic bacteria . Thirty-three women joining the WW were saliva sampled at the evening prior the day of the start of the dietary regimen and after 4 and 8 wk on the dietary regimen . No significant changes were found regarding saliva secretion rate and buffer effect . A significant decrease of salivary numbers of mutans streptococci and lactobacilli occurred . Between the 4th and 8th wk of dietary regimen an increase of cariogenic bacteria occurred but not back to the baseline values . At baseline 15 of the WW carried Streptococcus sobrinus in addition to Streptococcus mutans . The total number of salivary mutans streptococci and lactobacilli was significantly higher in those subjects . In conclusion the dietary regimen of the WW, based on food choice and distributions of meals in agreement with a non-cariogenic diet, reduced the number of cariogenic bacteria in most subjects, but not in all, while the secretion rate and buffer effect remained the same. Scand J Dent Res, 1992 Apr, 100(2), 111 - 6 Physiologic variation of sucrase activity and microbial counts in human saliva; Karjalainen S et al.; Quantitation of salivary sucrase activity has been proposed as a method for the estimation of the level of sucrose consumption . The purpose of the present study was to investigate the physiologic variability of the sucrase activity and microbial counts in paraffin-wax-stimulated saliva of subjects with sound sucrose consumption habits . Variation was analyzed by repeated sampling studies . Intraday variability was investigated by serial analyses of 16 individuals who gave eight samples at 2-h intervals on a single day . Interday variation was studied by analyzing the morning value of 24 individuals on three consecutive days . Interday variability of salivary mutans streptococci, lactobacilli, and yeasts was tested using semiquantitative commercial test kits . The diurnal variation of sucrase activity revealed that the activity in the morning was significantly higher than at noon or at later sampling times of the day . Interday variation was considerable in subjects with high sucrase values . The day-to-day variability of the salivary microbes was considerable for lactobacilli and relatively small for yeasts . A weak positive correlation ranging from 0.732 to 0.741 was found between high sucrase activity values and salivary lactobacilli . Salivary samples should be collected in the morning to differentiate between subjects with high and low sucrase activities. Community Dent Oral Epidemiol, 1992 Apr, 20(2), 76 - 80 Variation of posterior approximal caries incidence with consumption of sweets with regard to other caries-related factors in 15-18-year-olds; Sundin B et al.; The aim of this study was to analyze the relationships between caries incidence and a number of caries-related factors in 15-18-yr-olds, in order to estimate the explanatory value of consumption of sweets under different conditions . Sixty-nine 18-yr-olds were interviewed about consumption of sweets and other sugar-containing products during the past 3 yr . Data on oral hygiene, salivary counts of mutans streptococci and lactobacilli, salivary flow rate and oral sugar clearance time were collected when the individuals were 15 and 18 yr old . Caries incidence for the 3-yr period was expressed as a percentage of the number of caries-free approximal surfaces of premolars and molars at the age of 15 . Simple linear correlations between caries incidence and the different variables showed that lactobacilli count ranked first (r = 0.26), sweets second (r = 0.25), and mutans streptococci count third (r = 0.24) . The r value for caries incidence and consumption of sweets increased in subgroups with combinations of poor oral hygiene, a high intake of other sugary products and a low salivary flow rate (r = 0.67-0.70) . In conclusion, consumption of sweets should still be considered an important caries-related factor and particularly harmful when oral hygiene is poor and consumption of other sugary products is high. Antonie Van Leeuwenhoek, 1992 Apr, 61(3), 167 - 73 Effect of fermented oatmeal soup on the cholesterol level and the Lactobacillus colonization of rat intestinal mucosa; Molin G et al.; Rats were fed with freeze-dried oatmeal soup fermented by six different Lactobacillus strains from rat and man; the formula is intended for enteral feeding . The serum cholesterol levels after 10 d were lower for rats eating oatmeal as compared to a commercial product, Biosorb Sond . Colonizing ability of the administered strains were evaluated in vivo . Only Lactobacillus reuteri R21c were able to, effectively, colonizing the mucosa; it represented about 30% of the Lactobacillus population 24 d after termination of the administration . L . reuteri R21c was easily recognized by the ability to produce a yellow pigment on agar plates . The identity was confirmed by carbohydrate fermentations (API 50CH), plasmid pattern and endonuclease restriction analysis of the chromosomal DNA. J Appl Bacteriol, 1992 Apr, 72(4), 327 - 34 Factors affecting antibacterial activity of hop compounds and their derivatives; Simpson WJ et al.; The antibacterial effect of weak acids derived from the hop plant (Humulus lupulus L.) increased with decreasing pH . Analysis of the minimum inhibitory concentration of such compounds against Lactobacillus brevis IFO 3960 over pH 4-7 suggests that undissociated molecules were mainly responsible for inhibition of bacterial growth . The antibacterial activity of trans-isohumulone was ca 20 times greater than that of humulone, 11 times greater than that of colupulone and nine times greater than that of trans-humulinic acid when the degree of ionization was taken into account . Monovalent cations (K+, Na+, NH4+, Rb+, Li+) stimulated antibacterial activity of trans-isohumulone but the effect was smaller than that observed with H+ . The response to divalent cations varied: Ca2+ had little effect on antibacterial activity, whereas Mg2+ reduced activity . Lipid materials and beta-cyclodextrin also antagonized the antibacterial action of trans-isohumulone. Antonie Van Leeuwenhoek, 1992 Apr, 61(3), 175 - 83 Systematics of the Lactobacillus population on rat intestinal mucosa with special reference to Lactobacillus reuteri; Molin G et al.; The systematics of the Lactobacillus population of the intestines of 88 different rats was studied; 80 rats had been fed on fermented oat-meal soup (Molin et al . 1992) . One-hundred-twenty-two Lactobacillus strains from the intestinal mucosa were phenotypically classified together with twenty-eight reference strains of Lactobacillus and Leuconostoc, using 49 unit characters . Data were examined using Jaccard coefficient, and unweighted pair group algorithm with arithmetic averages . Two major and eleven minor clusters were defined at the 76% SJ-similarity level: Cluster 1 included thirty isolates which could not be identified further, but had resemblance to the type strains of L . jensenii, L . gasseri, L . crispatus, and to some extent to L . acidophilus . Cluster 12 including fifty-four intestinal isolates was identified as L . reuteri; and so was cluster 13 (five isolates) . Isolates of the major clusters were found in all parts of the intestines . The genomic homogeneity of the L . reuteri isolates was scrutinized by endonuclease restriction analysis of the chromosomal DNA, and the isolates could be divided into six genomic strains. FEMS Microbiol Lett, 1992 Mar 15, 70(3), 213 - 7 Competitive exclusion of diarrheagenic Escherichia coli (ETEC) from human enterocyte-like Caco-2 cells by heat-killed Lactobacillus; Chauviere G et al.; Diarrheagenic Escherichia coli (ETEC) bearing CFA/I or CFA/II adhesive factors specifically adhere onto the brush border of the polarized epithelial human intestinal Caco-2 cells in culture . Heat-killed Lactobacillus acidophilus strain LB, that adheres onto Caco-2 cells, inhibits diarrheagenic Escherichia coli adhesion in a concentration-dependent manner . Since the L . acidophilus does not express ETEC-CFA adhesive factors, it can be postulated that the heat-killed L . acidophilus LB cells inhibit diarrheagenic E . coli attachment by steric hindrance of the human enterocytic ETEC receptors. Obstet Gynecol, 1992 Mar, 79(3), 369 - 73 The relationship of hydrogen peroxide-producing lactobacilli to bacterial vaginosis and genital microflora in pregnant women; Hillier SL et al.; Lactobacilli provide an important microbial defense against genital colonization by pathogens . The role of hydrogen peroxide (H2O2) in the control of genital microflora was explored in a cross-sectional study of 275 women in the second trimester of pregnancy . Vaginal cultures were obtained for detection of H2O2-positive and H2O2-negative lactobacilli and other members of the genital microflora . Compared with women with H2O2-negative lactobacilli, women colonized by H2O2-positive lactobacilli were less likely to have bacterial vaginosis, symptomatic candidiasis, and vaginal colonization by Gardnerella vaginalis, Bacteroides, Peptostreptococcus, Mycoplasma hominis, Ureaplasma urealyticum, and viridans streptococci (P less than or equal to .05 for each comparison) . In addition to the above organisms, women without vaginal lactobacilli were more likely than those women with H2O2-positive lactobacilli to have Chlamydia trachomatis, and less likely to be colonized by Enterococcus or coagulase-negative staphylococci (P less than .05 for each comparison) . Vaginal colonization by group B streptococci or Escherichia coli was not related to the presence of H2O2-positive lactobacilli . These data suggest that the presence of H2O2-positive lactobacilli in the vagina is inversely correlated with infection by some genital pathogens in pregnant women. Ann Intern Med, 1992 Mar 1, 116(5), 353 - 7 Ingestion of yogurt containing Lactobacillus acidophilus as prophylaxis for candidal vaginitis; Hilton E et al.; OBJECTIVE: To assess whether daily ingestion of yogurt containing Lactobacillus acidophilus prevents vulvovaginal candidal infections . DESIGN: Crossover trial for at least 1 year during which patients were examined for candidal infections and colonizations while receiving either a yogurt-free or a yogurt-containing diet . Patients served as their own controls . SETTING: Ambulatory infectious disease center in a teaching hospital providing tertiary care . PATIENTS: Thirty-three women with recurrent candidal vaginitis were eligible after recruitment from community practices and clinics and through advertising . Twelve patients were eliminated for protocol violations . Of the remaining 21 patients, 8 who were assigned to the yogurt arm initially refused to enter the control phase 6 months later . Thus, 13 patients completed the protocol . INTERVENTIONS: Women ate yogurt for 6 months of the study period . MEASUREMENTS: Colonization of lactobacilli and candida in the vagina and rectum; candidal infections of the vagina . MAIN RESULTS: Thirty-three eligible patients were studied . A threefold decrease in infections was seen when patients consumed yogurt containing Lactobacillus acidophilus . The mean (+/- SD) number of infections per 6 months was 2.54 +/- 1.66 in the control arm and 0.38 +/- 0.51 per 6 months in the yogurt arm (P = 0.001) . Candidal colonization decreased from a mean of 3.23 +/- 2.17 per 6 months in the control arm to 0.84 +/- 0.90 per 6 months in the yogurt arm (P = 0.001) . CONCLUSION: Daily ingestion of 8 ounces of yogurt containing Lactobacillus acidophilus decreased both candidal colonization and infection. Mil Med, 1992 Mar, 157(3), 121 - 4 Effect of an experimental antiplaque preparation on salivary microbial counts in military academy cadets refraining from mechanical cleaning of the teeth; Nuuja MC et al.; Dental emergencies in the army are mostly due to infections of the teeth, caused by dental plaque micro-organisms . Because practicing normal oral hygiene is restricted during terrain maneuvers, for example, we developed a new antiseptic tablet preparation which can be used to make an antiplaque solution or even chewed and thus mixed with saliva to rinse the mouth . The preparation contains chlorhexidine, fluoride, and xylitol (XYLIHEX) and can be added to the soldier's kit . The efficiency of the preparation on selected oral micro-organisms was tested against mouthwash solutions containing plain chlorhexidine (CHX) and sodium fluoride (F) in 45 military cadets who volunteered to participate in this double-blind cross-over study . The results showed a significant decrease in salivary mutants streptococci after rinsing periods with XYLIHEX and CHX when compared with F (p less than 0.001) . Lactobacilli and yeast counts were not affected . The new preparation appeared promising as a new means for improving soldiers' oral hygiene. J Gen Microbiol, 1992 Mar, 138 ( Pt 3), 445 - 50 Temperature adaptation in Lactobacillus fermentum: interconversions of oleic, vaccenic and dihydrosterulic acids; Suutari M et al.; The interchange of octadecenoic acids and dihydrosterulic acid was a response of aerobically growing Lactobacillus fermentum to changes in growth temperature . Oleic and vaccenic acid contents decreased both at temperatures below 20 degrees C and above 26 degrees C, showing mirror image behaviour, with a concomitant increase in dihydrosterulic acid . A temperature-dependent shift from vaccenic to oleic acid synthesis, and the conversion of the latter to dihydrosterulic acid was responsible for the overall change . Consequently, the degree of fatty acid unsaturation decreased at temperatures above 26 degrees C, whereas the degree of cyclization increased . The converse occurred below 20 degrees C . The relative amount of lactobacillic acid, total cellular fatty acid content, and mean fatty acid chain length were practically temperature-independent . The occurrence of oleic acid is thought to be related to aerobic growth conditions. Appl Environ Microbiol, 1992 Mar, 58(3), 832 - 9 Cloning, sequence, and phenotypic expression of katA, which encodes the catalase of Lactobacillus sake LTH677; Knauf HJ et al.; Lactobacillus sake LTH677 is a strain, isolated from fermented sausage, which forms a heme-dependent catalase . This rare property is highly desirable in sausage fermentation, as it prevents rancidity and discoloration caused by hydrogen peroxide . A gene bank containing MboI fragments of chromosomal DNA from Lactobacillus sake LTH677 in Escherichia coli plasmid pBR328 was constructed . The catalase gene was cloned by heterologous complementation of the Kat- phenotype of E . coli UM2 . The catalase structural gene, designated katA, was assigned to a 2.3-kb region by deletion analysis of the originally cloned fragment in plasmid pHK1000 . The original chromosomal arrangement was determined by Southern hybridization . Protein analysis revealed that the catalase subunit has a molecular size of 65,000 Da and that the active catalase possesses a hexameric structure . The molecular size of the subunit deduced from the nucleotide sequence was determined to 54,504 Da . The N-terminal amino acid sequence of the 65,000-Da protein corresponded to the one deduced from the DNA sequence . After recloning of katA in the E . coli-Lactococcus shuttle vector pGKV210, the gene was successfully transferred and phenotypically expressed in Lactobacillus casei, which is naturally deficient in catalase activity. J Appl Bacteriol, 1992 Mar, 72(3), 214 - 9 Prevalence of coaggregation reactions among chicken lactobacilli; Vandevoorde L et al.; Interbacterial adherence was frequently encountered among chicken lactobacilli . Fourteen of 45 combinations involving nine adhering strains were shown to be coaggregative . The coadherence mechanism was mediated by complementary heat- and sonication-sensitive cell surface structures . It was shown that intrageneric adherence enabled lactobacilli to maintain higher numbers in fed-batch reactors simulating the gastrointestinal tract . The mechanism of coaggregation can substantially increase the colonization potential of lactobacilli in environments with short residence times. J Bacteriol, 1992 Mar, 174(6), 1750 - 9 Replacement of the folC gene, encoding folylpolyglutamate synthetase-dihydrofolate synthetase in Escherichia coli, with genes mutagenized in vitro; Pyne C et al.; The folylpolyglutamate synthetase-dihydrofolate synthetase gene (folC) in Escherichia coli was deleted from the bacterial chromosome and replaced by a selectable Kmr marker . The deletion strain required a complementing gene expressing folylpolyglutamate synthetase encoded on a plasmid for viability, indicating that folC is an essential gene in E . coli . The complementing folC gene was cloned into the vector pPM103 (pSC101, temperature sensitive for replication), which segregated spontaneously at 42 degrees C in the absence of selection . This complementing plasmid was replaced in the folC deletion strain by compatible pUC plasmids containing folC genes with mutations generated in vitro, producing strains which express only mutant folylpolyglutamate synthetase . Mutant folC genes expressing insufficient enzyme activity could not complement the chromosomal deletion, resulting in retention of the pPM103 plasmid . Some mutant genes expressing low levels of enzyme activity replaced the complementing plasmid, but the strains produced were auxotrophic for products of folate-dependent pathways . The folylpolyglutamate synthetase gene from Lactobacillus casei, which may lack dihydrofolate synthetase activity, replaced the complementing plasmid, but the strain was auxotrophic for all folate end products. Int J Food Microbiol, 1992 Mar-Apr, 15(3-4), 365 - 76 Glucose and sucrose fermenting capacity of homofermentative lactic acid bacteria used as starters in fermented salads; Bonestroo MH et al.; Salads, i.e., vegetables and/or meat in an oil-in-water emulsion with a low pH due to the addition of acids, are popular in western countries . The shelf life of these salads is influenced mainly by storage temperature and the use of preservatives, i.e., sorbic and benzoic acid . Lactic acid fermentation could be an interesting novel approach to salad preparation . As part of an investigation on fermented salads, lactic acid bacteria from the genera Lactobacillus, Pediococcus and Streptococcus were screened for their capacity to ferment glucose and sucrose in a model system and in a standard salad . The temperature optimum of these strains was in the range of 34-48 degrees C . Most of these strains produced about equal amounts of L(+)- and D(-)-lactic acid . To determine the specific sugar fermenting capacity (mmol lactic acid produced per min per g dry weight) of non-growing cells of lactic acid bacteria, a semi-automated model system was used, based on monitoring the pH decrease in a phosphate buffer during conversion of sugars to lactic acid . The strains tested showed acid production rates on glucose varying between 0.03 and 0.39 mmol of acid produced per min per g dry weight (average 0.23) . These glucose-grown cells showed varying, but lower fermentation rates on sucrose (0-0.25 mmol/min/g d.w., average 0.04) than sucrose-grown cells (0-0.33 mmol/min/g d.w., average 0.19) . Results obtained with the model system were in good agreement with those of fermentation tests, carried out with a standard salad . Inhibition of spoilage bacteria in the standard salad could be achieved by using starter cultures with high fermenting capacity. Am J Obstet Gynecol, 1992 Mar, 166(3), 938 - 44 Characteristics of three vaginal flora patterns assessed by gram stain among pregnant women . Vaginal Infections and Prematurity Study Group; Hillier SL et al.; This study was undertaken to define the characteristics and persistence of vaginal flora in 7918 pregnant women at 23 to 26 weeks' gestation . Vaginal smears were categorized as normal (predominant lactobacilli), intermediate (reduced lactobacilli), or positive for bacterial vaginosis . The women with normal flora were least likely to have elevated vaginal pH, amine odor, milky discharge, or colonization by Gardnerella, Bacteroides, or genital mycoplasmas . Women with intermediate vaginal flora had intermediate frequencies of these clinical signs and microorganisms . Group B streptococci and yeast were associated with normal or intermediate flora, whereas Neisseria gonorrhoeae and Chlamydia trachomatis were recovered more frequently from women with intermediate flora or bacterial vaginosis . Trichomonas vaginalis was most associated with intermediate flora . At follow-up, 81% of the women with normal flora had remained normal . Of the women with intermediate flora, 32% acquired bacterial vaginosis and 30% shifted to normal flora . Only 12% of the women with bacterial vaginosis had shifted to normal flora . We conclude that there are two primary stable vaginal flora patterns (normal flora or bacterial vaginosis) and a third less distinct transitional flora pattern between these two. Lett Appl Microbiol, 1992 Mar, 14(3), 72 - 6 Cloning and expression of the lysostaphin gene in Bacillus subtilis and Lactobacillus casei; Gaier W et al.; The lysostaphin structural gene was cloned in Bacillus subtilis DSM402 and in Lactobacillus casei 102S . The gene was expressed in both organisms and active lysostaphin was released into the medium . Lysostaphin produced by these organisms induced lysis of growing and heat inactivated staphylococci . Expression in a protective starter organism is a prerequisite to produce lysostaphin in situ in fermenting foods and hence, to reduce the hygienical risk of staphylococcal food poisoning. Eur J Biochem, 1992 Feb 15, 204(1), 173 - 7 31P-NMR assignment and conformational study of NADPH bound to Lactobacillus casei dihydrofolate reductase based on two-dimensional 1H-31P-heteronuclear and 1H-detected 1H-31P-shift-correlation experiments; Gerothanassis IP et al.; For any detailed NMR conformational study of a protein-ligand complex it is essential to have specific resonance assignments . We have now assigned the pyrophosphate 31P resonances in spectra of NADPH bound to Lactobacillus casei dihydrofolate reductase (DHFR) by using a combination of 1H-31P-heteronuclear shift-correlation (HETCOR), 1H-31P-heteronuclear multiple-quantum-coherence correlation spectroscopy (HMQC-COSY), 1H-1H COSY, homonuclear Hartmann-Hahn (HOHAHA) and NOE spectroscopy (NOESY) experiments . The nicotinamide pyrophosphate phosphorus, P(n), has been unequivocally assigned to a signal (-14.07 ppm) which shows a large 3JP-O-C-H coupling constant . Such a coupling constant when combined with the appropriate Karplus relationship provides conformational information about the P-O-C-H torsion angle . The torsion angle changes by 65 degrees +/- 10 degrees for the binary complex compared with the value in free NADPH . The observed coupling constants for the binary (DHFR--NADPH) and ternary (DHFR--NADPH--methotrexate) complexes (12.3 and 10.5 +/- 0.6 Hz, respectively) indicate that the pyrophosphate group has a similar conformation in the two complexes. J Med Microbiol, 1992 Feb, 36(2), 112 - 6 The protective activity of immunostimulants against Listeria monocytogenes infection in mice; Tomioka H et al.; The function of peritoneal macrophages induced by intraperitoneal (i.p.) injection of attenuated Streptococcus pyogenes (OK-432), Bacillus Calmette Guerin (BCG), protein-bound polysaccharide preparation isolated from Coriolus vesicolor (PSK) or Lactobacillus casei was examined . The PMA-triggered respiratory burst (production of O2- and H2O2) of macrophages induced by OK-432, BCG or Lac . casei was greater than that of resident or thioglycollate-stimulated macrophages and was similar to that of BCG-activated macrophages . PSK failed to enhance the production of O2- or H2O2 by macrophages . Alkaline phosphodiesterase (APD) activity was reduced in macrophages induced by OK-432, BCG or Lac . casei injection and in BCG-activated macrophages . The APD activity of macrophages obtained 7 and 13 days after i.p . injection of PSK was elevated, as with thioglycollate-stimulated macrophages . Listericidal activity in vitro was enhanced in macrophages obtained in 13 and 7 days, but suppressed in macrophages obtained 2 days after OK-432, BCG or Lac . casei injection . Lac . casei administered either 2 or 13 days before infection with Listeria monocytogenes was protective but OK-432, BCG (0.1 mg) and PSK were not, even though they were able to stimulate macrophage function. J Bacteriol, 1992 Feb, 174(3), 1013 - 9 Sugar-glycerol cofermentations in lactobacilli: the fate of lactate; Veiga da Cunha M et al.; The simultaneous fermentation of glycerol and sugar by lactobacillus brevis B22 and Lactobacillus buchneri B190 increases both the growth rate and total growth . The reduction of glycerol to 1,3-propanediol by the lactobacilli was found to influence the metabolism of the sugar cofermented by channelling some of the intermediate metabolites (e.g., pyruvate) towards NADH-producing (rather than NADH-consuming) reactions . Ultimately, the absolute requirement for NADH to prevent the accumulation of 3-hydroxypropionaldehyde leads to a novel lactate-glycerol cofermentation . As a result, additional ATP can be made not only by (i) converting pyruvate to acetate via acetyl phosphate rather than to the ethanol usually found and (ii) oxidizing part of the intermediate pyruvate to acetate instead of the usual reduction to lactate but also by (iii) reoxidation of accumulated lactate to acetate via pyruvate . The conversion of lactate to pyruvate is probably catalyzed by NAD-independent lactate dehydrogenases that are found only in the cultures oxidizing lactate and producing 1,3-propanediol, suggesting a correlation between the expression of these enzymes and a raised intracellular NAD/NADH ratio . The enzymes metabolizing glycerol (glycerol dehydratase and 1,3-propanediol dehydrogenase) were expressed in concert without necessary induction by added glycerol, although their expression may also be influenced by the intracellular NAD/NADH ratio set by the different carbohydrates fermented. Antimicrob Agents Chemother, 1992 Feb, 36(2), 361 - 7 Prevention of indigenous infection of mice with Escherichia coli by nonspecific immunostimulation; Nomoto K et al.; We have previously reported that the lethal toxicity of 5-fluorouracil (5-FU) in specific-pathogen-free mice is due to an intestinal infection with indigenous Escherichia coli induced by the drug (K . Nomoto, T . Yokokura, Y . Yoshikai, M . Mitsuyama, and K . Nomoto, Can J . Microbiol . 37:244-247, 1991) . In the present study we demonstrate that nonspecific immunostimulation is effective in the protection of mice from the lethal indigenous infection induced by 5-FU . Intravenous or subcutaneous injection of a preparation of heat-killed Lactobacillus casei YIT 9018, a potent nonspecific immunostimulant, into BALB/c mice reduced the lethal toxicity of 5-FU at doses ranging from 338 to 800 mg/kg of body weight if YIT 9018 was injected 7 to 40 days before administration of 5-FU . Systemic infection with E . coli developed in all of the 5-FU-treated control mice 7 days or more after administration of 5-FU in large doses and was accompanied by overgrowth of the bacteria in the intestinal tract . Pretreatment of mice with YIT 9018 resulted in a decreased occurrence of systemic infection with E . coli to levels of 0 to 20% and no significant changes in the population levels of E . coli in the intestinal tract during the 14 days after administration of 5-FU . The levels of leukopenia in the spleen and peripheral blood were lower, and recovery of granulocyte-macrophage precursor cells in the spleen and femur began earlier in the treated animals than in the 5-FU-treated controls . Intravenous transfusion of syngeneic normal bone marrow cells or spleen cells into the mice at an early period after administration of 5-FU diminished markedly the occurrence of the lethal indigenous infection, suggestion that an earlier recovery from chemotherapy-induced myelosuppression is important in the mechanisms of protection of the host from the infection. J Gen Microbiol, 1992 Feb, 138 ( Pt 2), 313 - 8 Purification and N-terminal amino acid sequence determination of the cell-wall-bound proteinase from Lactobacillus paracasei subsp . paracasei; Naes H et al.; The cell-wall-bound proteinase from Lactobacillus paracasei subsp . paracasei NCDO 151 was purified to homogeneity by anion-exchange and hydrophobic-interaction chromatography, chromatofocusing and gel-filtration . The purification resulted in a 600-700-fold increase in specific activity of the proteinase and the final yield was approximately 20% . Upon chromatofocusing, two proteolytically active components, termed pro135 and pro110, were detected . pro135 had an isoelectric point of 4.2 . It had an Mr of about 300,000 as determined by gel-filtration and 135,000 as judged by SDS-PAGE, indicating that it may exist as a dimer in its native state . pro110 had an isoelectric point of 4.4, and an Mr of about 150,000 as determined by gel-filtration and 110,000 as judged by SDS-PAGE . pro110 appears to be a degradation product of pro135 as they have the same N-terminal amino acid sequence . The first N-terminal amino acid was ambiguous for both components, whereas the sequence from the second to the ninth amino acid was Ala-Lys-Ala-Asn-Ser-Met-Ala-Asn . This is identical to the corresponding sequence of the lactococcal cell-wall-bound proteinases . Although the Lactobacillus proteinase was a little smaller than the lactococcal proteinase, their purification characteristics were very similar, suggesting that these proteinases are related. Community Dent Oral Epidemiol, 1992 Feb, 20(1), 35 - 7 Multifactorial modeling for root caries prediction; Scheinin A et al.; The study was part of a series of investigations aiming at the development of diagnostic caries tests for screening of risk subjects . The material consisted of 100 adult subjects (mean 62 yr, range 47-79 yr), 50 of these under chronic medication . The series of tests included two chairside registrations, i.e . incipient demineralization of exposed root surfaces without cavitation (RD 1) and quantitation of visible plaque (VPT%), three microbiological tests for mutans streptococci, lactobacilli, and candida/yeasts and three tests on stimulated saliva, i.e . secretion rate, buffering capacity and sucrase activity . A thorough clinical examination was conducted at the baseline and 1-yr registration phases, caries being registered at a tooth surface level according to WHO recommendations separately for coronal and root caries . Considerably more root caries than coronal caries developed during the observation period . For coronal caries increment, the predictive value of any of the tests was not significant . For root caries, however, the association between several tests and prospective caries increment was significant . Subsequent multifactorial modeling yielded the highest predictive value to the combination of Past Root Caries Experience (OR 25.0, Visible Plaque (OR 4.2), Candida (OR 8.0) and Lactobacilli (OR 5.8) . A positive finding of Past Root Caries (RDFS) or the combination of the other three tests (Can, LB, VPT%) as criteria for selection in screening for root caries produced good accuracy (84.0) and a relative risk of 5.5. Biosci Biotechnol Biochem, 1992 Feb, 56(2), 223 - 7 Sequence analysis of replication origin of plasmid pLS11 of Bacillus subtilis IFO 3022; Hara T et al.; The structure of a 1.6-kb SphI-HindIII DNA sequence necessary and sufficient for the replication of a 8.6-kb plasmid pLS11 of Bacillus subtilis IFO 3022, which is responsible for gamma-polyglutamate production, has been characterized by using a trimethoprim (Tmp)-resistance gene derived form B . subtilis TTK24 chromosomal DNA as a selective marker . The 1.6-kb DNA sequence contains a rep gene encoding the protein (333 amino acids) essential for initiation of replication and a possible origin of replication . The predicted REP protein of pLS11 has an overall homology with the REP proteins of pUH1 (74.8% identity), pBAA1 (92.8%), and pFTB14 (78.7%) in Bacillus spp., pLP1 (42.1%) and pLAB1000 (36.3%) in Lactobacillus spp., and pUB110 (35.3%) and pC194 (37.4%) in Staphylococcus aureus, but has not any similarity with the REP protein of the staphylococcal plasmid pT181. Biosci Biotechnol Biochem, 1992 Feb, 56(2), 190 - 4 Establishment of a host-vector system in Lactobacillus helveticus with beta-galactosidase activity as a selection marker; Hashiba H et al.; A host-vector system was established in Lactobacillus helveticus with beta-galactosidase activity as a selection marker . Plasmid pBG10 was constructed by joining the beta-galactosidase gene from L . bulgaricus, the promoter region of the erythromycin resistance gene from pAM beta 1, the replication region of pBR329, and the replication region of the L . helveticus cryptic plasmid pLJ1 . L . helveticus SBT2195 (Lac- mutant), transformed with pBG10, was selected on skim milk plates . The structural gene of alpha-amylase (1536 bp) from Bacillus licheniformis, inserted downstream of the promoter region of the erythromycin resistance gene of pBG10, was expressed in L . helveticus SBT2195 . Plasmid pBG10 is a food-grade and expression vector in L . helveticus. J Parasitol, 1992 Feb, 78(1), 157 - 60 Interactions between Trichomonas vaginalis and vaginal flora in a mouse model; Meysick KC et al.; To study the role of vaginal flora and pH in the pathogenesis of Trichomonas vaginalis, an intravaginal mouse model of infection was established . By employing this model, the vaginal flora and pH of mice could be monitored for changes caused by the parasite . As a baseline, the endemic vaginal flora of BALB/c mice was examined first and found to consist mainly of Staphylococcus aureus and Enterococcus species (32-76%) . Lactobacilli and enteric bacilli were moderate (16-32%) in their frequency of isolation, and the prevalence of both anaerobic species and coagulase-negative staphylococci was low (4-16%) . Vaginal pH was recorded at 6.5 +/- 0.3 . Estrogenization, which was required for a sustained T . vaginalis infection, did not significantly alter vaginal flora; however, a slight rise in the number of bacterial species isolated per mouse and a drop in vaginal pH (6.2 +/- 0.5) were observed . Trichomonas vaginalis-infected mice did not appear to show significant changes in vaginal flora although vaginal pH was slightly increased . This mouse model could have applications in both immunologic and pathogenic studies of T . vaginalis and, with further modifications, aid in the study of protist-bacterial interactions. Caries Res, 1992, 26(4), 268 - 74 Effect of slow-release chlorhexidine mouthguards on the levels of selected salivary bacteria; Hildebrandt GH et al.; This study evaluated the effect of an alternate delivery system for chlorhexidine on salivary levels of mutans streptococci (MS) and other selected oral bacteria . On the basis of salivary MS levels > or = 10(4) CFU/ml, 22 subjects were enrolled . All caries lesions were restored prior to treatment . Two pretreatment paraffin-stimulated saliva samples were obtained for culturing at least 1 week apart . Complete-arch vacuum-adapted mouthguards were individually fabricated and coated internally with a 3% w/v chlorhexidine varnish . Mouthguards were worn for an average of 7 h/night for 7 nights . Saliva samples were obtained immediately after treatment and 1 and 3 months later . There was no significant change in levels of any of the monitored bacteria between the two pretreatment samples . A significant and specific reduction in salivary MS levels was observed in the three after-treatment samples as compared with baseline values (p < 0.001, p < 0.001, p < 0.05, respectively) . The levels of Actinomyces viscosus were also measured, and there was a significant reduction immediately after treatment (p < 0.05), a return to baseline values at 1 month, and a significant increase above baseline values at 3 months, (p < 0.001) . There was no significant change in saliva volume, in total numbers of facultatively anaerobic bacteria, or in levels of lactobacilli or Streptococcus sanguis . This treatment system is capable of significant and specific suppression of MS levels for up to 3 months without retreatment. Eur J Obstet Gynecol Reprod Biol, 1992 Jan 9, 43(1), 13 - 8 Detection of Candida cell forms in Pap smears during pregnancy; Donders GG et al.; In a prospective study of 124 urban black pregnant women, 43% had Candida isolated from endocervical cultures and 20% had Candida cell forms on cytological Pap-stained cervical specimens . The presence of Candida cell forms on Pap smears had a better correlation with Candida colonisation when normal lactobacillary flora was present, when Trichomonas vaginalis parasites were absent and when the infecting Candida species was C . albicans . Positive cultures were strongly related to a number of clinical signs and symptoms, but Pap smears were not . Neither Candida culture nor Candida cells in Pap smear revealed an association with premature delivery, birth weight, severe neonatal morbidity or mortality . We confirm that the routine cervical Pap smear is not a sensitive method for diagnosing symptomatic fungal infection . More specifically, some of the Pap smear characteristics, such as disturbed lactobacillary flora or co-infection with T . vaginalis, interfere with accurate diagnosis. Caries Res, 1992, 26(3), 183 - 7 Mutans streptococci and lactobacilli in breast-fed children with rampant caries; Matee MI et al.; This study aimed to investigate the prevalence of selected components of the oral microflora in breast-fed children who developed rampant caries (resembling nursing caries) under hitherto unexplained circumstances . Dental plaque and saliva samples were collected from breast-fed children, aged between 1 and 2.5 years, with and without rampant caries . Mutans streptococci and lactobacilli were isolated from dental plaque of all children with rampant caries and from most caries-free children . None of the colonies of mutans streptococci resembled those of Streptococcus sobrinus . The mean counts of the mutans streptococci and lactobacilli were 100-fold higher in plaque samples from children with rampant caries as compared with caries-free children . No difference could be found between the numbers of mutans streptococci in plaque overlaying cavities and that from adjacent sound enamel . In contrast, the counts of lactobacilli in plaque were approximately 100-fold higher from cavities than from sound surfaces . The levels of mutans streptococci in saliva were directly related to the presence of rampant caries . The results show that caries-free and caries-active breast-fed children, aged 1 to 2.5 years, harbour mutans streptococci and lactobacilli on their teeth . Rampant caries in these children can occur in the absence of nursing bottles or any other feeding abuse during weaning and in the presence of an aciduric plaque microflora, as has been reported for children with nursing bottle caries. Int J Food Microbiol, 1992 Jan-Feb, 15(1-2), 99 - 108 Chemical, microbial and sensory changes during the anaerobic cold storage of beef inoculated with a homofermentative Lactobacillus sp . or a Leuconostoc sp; Borch E et al.; Slices of beef were inoculated with about 3.5 log cfu/cm2 of Lactobacillus sp . 93 SMRICC 235 (homofermentative) or Leuconostoc sp . 89 SMRICC 189 and stored in 5% CO2 + 95% N2 at 4 degrees C . The microbial, chemical (glucose, L-lactate, D-lactate, acetate, formate, ethanol, H2S) and sensory changes of the beef slices were studied . For beef inoculated with Lactobacillus sp . 93 the flavour score started to decrease when the maximum bacterial count was reached . Leuconostoc sp . 89 caused a rapid decrease in the flavour score before reaching the maximum bacterial count . Concentrations of acetate and D-lactate increased while glucose and L-lactate decreased in beef slices inoculated with Lactobacillus sp . 93 . In the presence of Leuconostoc sp . 89 ethanol and D-lactate increased while glucose decreased . Lactobacillus sp . 93 formed the highest level of H2S, and a sulphurous off-odour was noted only in the presence of this strain . D-Lactate and acetate indicated high numbers of Lactobacillus sp . 93 on the meat surface, while D-lactate and ethanol indicated high numbers of Leuconostoc sp . 89 . More studies are needed in order to correlate levels of D-lactate, acetate and ethanol with sensory changes. Int J Food Microbiol, 1992 Jan-Feb, 15(1-2), 87 - 98 Purification of X-prolyl dipeptidyl aminopeptidase from Lactobacillus casei subspecies; el Abboudi M et al.; Prolyl dipeptidylaminopeptidases from two subspecies of Lactobacillus casei were purified and biochemically characterized . L . casei ssp . casei UL21 (a debittering strain) and L . casei ssp . rhamnosus UL26 (a non-debittering strain) were the source bacteria for this study . Purification of the enzymes from both the sources was effected by a gel filtration step through Sephacryl S-300 followed by ion-exchange chromatography through DEAE Sephacel . This rendered an electrophoretically homogeneous enzyme preparation . The purified enzymes from both the sources showed similar temperature optimum (45 degrees C) and pH optimum (7.0) . Their activity profiles on various substrates and the nature of inhibition by different inhibitors were also found to be similar, indicating that this enzyme is perhaps not significantly involved in the debittering process during the maturation of cheese. Int J Food Microbiol, 1992 Jan-Feb, 15(1-2), 177 - 84 The effect of resuscitation and the incubation-temperature on recovery of uninjured, heat injured and freeze injured enterococci; Ewald S et al.; Five strains of enterococci were inoculated on the Slanetz and Bartley enterococcus agar (EA), and incubated at 37 degrees C and 44 degrees C following: no injury, heat-injury and freeze-injury . The experiments were repeated introducing a 2 h resuscitation step in Tryptic Soy Agar (TSA) at 37 degrees C and subsequent overlay with EA (TSA/EA) followed by incubation at both 37 degrees C and 44 degrees C . The TSA/EA method gave a significantly better recovery (1% confidence level) than the EA method at both 37 degrees C and 44 degrees C . The effect of incubation-temperature was only significant for two strains of Enterococcus durans, as one strain showed no growth at 44 degrees C and the other strain was recovered significantly (5% confidence level) better at 37 degrees C that at 44 degrees C when employing the EA method . Interpretation of the results using TSA/EA method was easier than that of the EA . Different lactic streptococci and lactobacilli commonly employed in the dairy industry did not develop false positive colonies in TSA/EA incubated at 37 degrees C. Int J Food Microbiol, 1992 Jan-Feb, 15(1-2), 145 - 52 Headspace flavour compounds produced by yeasts and lactobacilli during fermentation of preferments and bread doughs; Torner MJ et al.; Production of volatile flavour compounds during fermentation with pure cultures of Saccharomyces cerevisiae and Candida guilliermondii, Lactobacillus brevis and Lactobacillus plantarum have been investigated, using wheat doughs and several preferements as substrates . For yeast, preferments consisted of 10% (w/v) glucose, maltose and sucrose solutions, whereas for lactobacilli they consisted of supplemented and unsupplemented (3% and 10% (w/v)) glucose solutions, and a 10% (w/v) wheat flour slurry . Seven volatile compounds (acetaldehyde, acetone, ethyl acetate, ethanol, hexanal+isobutyl alcohol, and propanol) were detected when using yeasts . All these compounds, except propanol, appeared for all the substrates assayed, with ethanol as the predominant component . Generally, S . cerevisiae produced higher amounts of the different components than C . guilliermondii . Both yeasts produced larger amounts of volatile flavour compounds during fermentation in glucose and sucrose solutions than in maltose or wheat dough . In general the yeasts examined produced more flavour components than the lactobacilli . For the lactobacilli the highest number of volatile flavour compounds were observed for substrates containing flour. Microbiol Immunol, 1992, 36(3), 311 - 5 Interferon induction in murine peritoneal macrophage by stimulation with Lactobacillus acidophilus; Kitazawa H et al.; Induction of interferon for a kind of dairy lactic acid bacteria, Lactobacillus acidophilus (L . acidophilus), was investigated in murine peritoneal macrophage (M phi) cultures . Lactobacillus acidophilus JCM 1034, 1132T, 1229 and 2125 induced IFN (12-34 I.U./ml) in M phi cultures in vitro . Strain 1132T- and 2125-induced IFNs were characterized as IFN alpha/beta by treatment with anti-IFNs serum . The results indicate that the inducing activity of IFNs may be one of the available biological parameters for designating the dairy products containing L . acidophilus as "physiologically functional foods." Microbiol Immunol, 1992, 36(3), 297 - 301 Heterogeneity of S-layer proteins of Lactobacillus acidophilus strains; Masuda K; An S-layer (surface regular array) was found in the cell wall from six out of ten strains of Lactobacillus acidophilus examined by electron microscopic observations . All of the six strains which were shown to carry the S-layers belonged to the deoxyribonucleic acid (DNA) homology group A, but not to B, which had been classified by Johnson et al (Int . J . Syst . Bacteriol . 30: 53-68, 1980) . On the other hand, the other four strains which possessed no S-layers were in the homology group B . The apparent molecular weights of the S-layer proteins ranged from 41 to 49 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . Of the S-layer proteins from the six strains, three were susceptible to chemical cleavage with N-chlorosuccinimide, giving different peptide maps . All of the six S-layer proteins were fragmented by limited proteolysis with Staphylococcus aureus V8 protease, and gave markedly different peptide patterns by the subsequent peptide mapping analysis, except that the peptide maps of the S-layer proteins from the two strains which were in the same subgroup were identical. Acta Vet Scand, 1992, 33(1), 95 - 103 Lactic acid bacteria for mink . Colonization and persistence of Enterococcus faecium Cernelle 68 in the digestive tract of mink; Pedersen K et al.; A method was developed to follow a lactic acid bacterial strain, Enterococcus faecium Cernelle 68, with respect to adhesion, multiplication, colonization, and persistence in the digestive tract of mink . Also the spread of the strain in the cage was examined . When adding 5 x 10(9) c.f.u . of a rifampicin resistant mutant per kg feed, high viable counts were registered throughout the digestive tract, apart from the oesophagus . Counts were increasing in the aboral direction, suggesting some multiplication in the intestine . It was possible to detect the strain in the intestinal tract 4 days after discontinuation of administration . Neither culture nor scanning electron microscopy gave evidence to suggest that E . faecium Cernelle 68 adhered to the mucosa . The spread of the E . faecium strain was observed in the environment . Counts of E . coli, lactobacilli, staphylococci, and clostridia were low, and none of these bacteria were constant findings. Acta Vet Scand, 1992, 33(1), 27 - 32 Effect of sodium nitrite and sodium chloride on growth of lactic acid bacteria; Korkeala H et al.; The effect of NaNO2 and NaCl on the growth of 24 lactic acid bacteria strains isolated from vacuum-packed cooked ring sausages were examined by analyzing different growth parameters with Bioscreen . NaNO2 had a very limited effect on the growth of lactic acid bacteria at 50 and 100 mg/l but at 400 mg/l a more pronounced inhibitory effect was found . Bacterial growth was enhanced by 1-2% (w/v) of added NaCl, while NaCl concentrations above 3% (w/v) had a clear inhibitory effect . Leuconostoc isolates seemed to be more sensitive to sodium nitrite and sodium chloride than homofermentative lactobacilli strains . Among homofermentative lactobacilli, the strains resembling Lactobacillus curvatus were more sensitive to NaCl than those resembling Lactobacillus sake. Int J Vitam Nutr Res, 1992, 62(1), 34 - 42 Microbiological methods of thiamine measurement in biological material; Olkowski AA et al.; Semiautomated, microbiological methods for the determination of thiamine in a variety of biological material are presented . Thiamine content was measured in bovine, ovine and rat blood, plasma, bile, urine, duodenal fluid, liver, kidney and brain . Thiamine was extracted from samples by mild acid digestion (trans aconitate pH 4.0) at 115 degrees C for 20 min . Microbiologic assays utilizing Lactobacillus fermenti and Ochromonas danica were performed on 96-well microplates and growth, as monitored by optical density, was directly read on a microplate reader at 650 nm . Particular attention was given to the validation of the two methods in terms of accuracy, reproducibility and recovery . The microbiological methods described here are specific, sensitive, and ensure good reproducibility . The methods can be used to analyse a large number of samples rapidly and at low cost. J Anim Sci, 1992 Jan, 70(1), 196 - 206 Effect of feeding organic acids on selected intestinal content measurements at varying times postweaning in pigs; Risley CR et al.; Pigs weaned at 21 d of age (n = 72) were fed a 20% CP corn-soybean meal-based diet (control) with 1.5% fumaric or 1.5% citric acid added to observe the effect of these acids on the pH, chloride ion concentration (Cl-), VFA profile, and microflora population in the stomach, jejunum, cecum, and lower colon contents at -2, 0, 3, 7, 14, and 21 d postweaning . Feeding organic acids had no appreciable effect (P greater than .10) on stomach jejunum, cecum, or lower colon pH, Cl-, VFA profile, or microflora populations, except for increasing the concentration of fumaric acid in the stomachs of pigs fed fumaric acid . The pH of the gastrointestinal tract generally decreased from -2 to 21 d postweaning with no corresponding change in Cl- over time . No age effects on total anaerobic culture counts were observed except in the stomach, where counts decreased from -2 to 3 d postweaning . Clostridia counts generally decreased after weaning in all intestinal sections . Lactobacillus counts were usually lower at d 0 and 3 and greatest at d 7 postweaning in the stomach, jejunum, and lower colon, but no age effect was observed for concentration of cecum lactobacilli . Escherichia coli counts generally increased after weaning to 3 and 7 d postweaning . Intestinal content measurements were affected by postweaning age but were not affected by feeding organic acids. Can J Microbiol, 1992 Jan, 38(1), 69 - 74 Construction of a new shuttle vector for Lactobacillus; Chagnaud P et al.; To clone the malolactic enzyme gene from Lactobacillus sp . 89, construction of a shuttle vector able to express itself in Lactobacillus sp . 89 and Escherichia coli was undertaken . The shuttle plasmid pLE16 resulted from the union of pBR328 and of the pLB10 plasmid extracted from Lactobacillus bulgaricus 10 . The bacterial transformation in Lactobacillus sp . 89 was performed by electroporation, and the clones were selected on MRS medium with 30 micrograms.mL-1 chloramphenicol added . Fifty percent of the clones from Lactobacillus sp . 89 lost their resistance to chloramphenicol following 28 generations when the selection pressure was not maintained . The restriction map of pLE16 (7600 bp) was established using several restriction enzymes. Chin Med J (Engl), 1992 Jan, 105(1), 25 - 9 Multibacterial artificial plaque . A model for studying carious process; Yue SL et al.; A multibacterial artificial plaque was established in vitro on enamel slabs incubated in mixed culture of Streptococcus sanguis, Streptococcus mutans (serotype c), Streptococcus salivarius, Lactobacillus casei and Actinomyces viscosus . Typical structure same as natural plaque was seen under microscope . The caries-like lesion produced under the plaque was observed in enamel sections . The lesion was similar in appearance to natural ones under optic and scanning electron microscopes . The acids produced in both culture media and artificial plaque were similar in composition and type to those produced in natural plaque after sugar attack . It is suggested that this kind of plaque model may be useful in studying carious process in vitro, because it is easily controlled either by changing the composition of bacteria or by adding different kinds of nutrient in the media . Moreover, the results will be easier to explain than those produced in natural ones. Clin Ther, 1992 Jan-Feb, 14(1), 11 - 6 Influence of three-day antimicrobial therapy and lactobacillus vaginal suppositories on recurrence of urinary tract infections; Reid G et al.; Forty-one adult women with acute lower urinary tract infections (UTI) were randomly treated for three days with norfloxacin or trimethoprim/sulfamethoxazole (TMP/SMX) . Infection was eradicated in 100% of norfloxacin-treated patients and in 95% of TMP/SMX-treated patients . UTI recurred in 29% of patients treated with norfloxacin and in 41% of those treated with TMP/SMX . Post-therapy vaginal administration of lactobacillus suppositories resulted in a recurrence rate of UTI of only 21%, while in patients given sterilized skim-milk suppositories the recurrence rate was 47% . This study indicates that lactobacillus vaginal suppositories are safe and may be effective in reducing the recurrence of UTI following antimicrobial therapy. Gynecol Obstet Invest, 1992, 33(2), 119 - 23 Could bacterial vaginosis be due to the competitive suppression of lactobacilli by aerobic microorganisms? Fredricsson B, Englund K, Nord CE, Weintraub L. Bacterial vaginosis (BV) is characterized by lack of lactobacilli and predominance of anaerobic species . Ciprofloxacin is active against a great number of aerobic bacteria . The effect of ciprofloxacin on the vaginal microbial flora was studied both in healthy subjects and in patients with BV in order to test if BV may be due to competitive suppression of lactobacilli by aerobic species . About half of the patients were relieved of their symptoms . No adverse effects on the microbial profile or colonization by lactobacilli were produced by the drug . Lactobacilli known to be able to produce hydrogen peroxide were found to be significantly more common in healthy women than in women with BV . The species most frequently related to vaginal health were Lactobacillus jensenii and Lactobacillus rogosae. Z Geburtshilfe Perinatol, 1992 Jan-Feb, 196(1), 1 - 6 {Infections of the lower genital tract in asymptomatic pregnant women--a prospective study}; Puchner T; In a prospective study, 70 symptom free pregnant women were investigated (native secretion microscopy, vaginal culture, chlamydial smear, gonococcal culture) several times during pregnancy to determine the bacterial invasion of the lower genital tract . In view of the frequency of the presence of manifold pathogenic organisms found in these women without symptoms at widely different stages in pregnancy, danger of premature birth, the necessity of tocolysis or potential administration of cortisone to mature the lungs and indefinite symptoms in the pregnant woman, should give rise to an exact investigation of the lower genital tract, respecting possible infections . None of the pathogenic organisms which were found in the group of symptom free women in their pregnancy had any influence on the outcome of pregnancy or on the morbidity of the child . The presence of the lactobacillus in this group of symptom free pregnant women probably plays the decisive role. Appl Environ Microbiol, 1992 Jan, 58(1), 215 - 20 Jenseniin G, a heat-stable bacteriocin produced by Propionibacterium jensenii P126; Grinstead DA et al.; The genus Propionibacterium includes cutaneous species typically found on human skin and the dairy or classical species (Propionibacterium freudenreichii, P . jensenii, P . thoenii, and P . acidipropionici) used industrially for the production of Swiss cheese and propionic acid . Grinstead (1989, M.S . thesis, Iowa State University, Ames) has previously observed that some dairy propionibacteria inhibit other species in the classical grouping . We further investigated the inhibitor(s) produced by P . jensenii P126 (ATCC 4872) . An antagonist(s) from anaerobic agar cultures of P126 strongly inhibited two closely related strains of propionibacteria, P . acidipropionici P5 and P . jensenii P54, and Lactobacillus bulgaricus NCDO 1489, Lactobacillus delbrueckii subsp . lactis ATCC 4797, Lactococcus cremoris NCDO 799, and Lactococcus lactis subsp . lactis C2 . The inhibitor, designated jenseniin G, was active at pH 7.0; inactivated by treatment with pronase E, proteinase K, and type 14 protease; insensitive to catalase; and stable to freezing, cold storage (4 degrees C, 3 days), and heat (100 degrees C, 15 min) . Classification of the inhibitor as a bacteriocin is supported by its proteinaceous nature and its bactericidal activity against L . delbrueckii subsp . lactis ATCC 4797 . The lack of detectable plasmids suggests a chromosomal location for the determinant(s) of jenseniin G. Caries Res, 1992, 26(2), 124 - 31 Effects of hyposalivation on the oral microflora of rats fed sucrose or wheat flour diets; Ooshima T et al.; The effects of hyposalivation on the induction of dental caries and on the composition of the oral microflora were examined in specific pathogen-free Sprague-Dawley rats fed either a sucrose or a wheat flour diet with or without inoculation of Streptococcus mutans . Significant dental caries was induced in hyposalivated rats fed diet 2000 containing 56% sucrose, irrespective of infection by S . mutans . Diets containing 56% wheat flour did not induce dental caries in either hyposalivated or sham-operated rats, irrespective of infection by S . mutans . Bacteriological examinations at the end of the experiment demonstrated that the total numbers of lactobacilli and staphylococci increased in hyposalivated rats irrespective of the diet given, while the inoculated stain of S . mutans decreased significantly in hyposalivated rats . These findings suggest that some acidogenic microorganisms such as lactobacilli and staphylococci that can utilize sucrose or glucose but not wheat flour may also promote dental caries in hyposalivated rats. Microbiol Immunol, 1992, 36(5), 533 - 8 Existence of phosphoenolpyruvate: carbohydrate phosphotransferase systems in Lactobacillus fermentum, an obligate heterofermenter; Nagasaki H et al.; The presence or absence of the phosphoenolpyruvate: carbohydrate phosphotransferase system (PTS) in obligately heterofermentative group III lactobacilli including Lactobacillus brevis (3 strains), L . buchneri (2 strains) and L . fermentum (3 strains) was surveyed systematically for a series of sugars utilizable by these organisms . Contrary to common expectation, PTSs were found in two strains of L . fermentum: sucrose-PTS in one strain; sucrose- and mannose-PTSs in the other . All these activities were found to be constitutive. Arch Microbiol, 1992, 157(5), 457 - 63 Energy conservation in malolactic fermentation by Lactobacillus plantarum and Lactobacillus sake; Kolb S et al.; A comparably poor growth medium containing 0.1% yeast extract as sole non-defined constituent was developed which allowed good reproducible growth of lactic acid bacteria . Of seven different strains of lactic acid bacteria tested, only Lactobacillus plantarum and Lactobacillus sake were found to catalyze stoichiometric conversion of L-malate to L-lactate and CO2 concomitant with growth . The specific growth yield of malate fermentation to lactate at pH 5.0 was 2.0 g and 3.7 g per mol with L . plantarum and L . sake, respectively . Growth in batch cultures depended linearly on the malate concentration provided . Malate was decarboxylated nearly exclusively by the cytoplasmically localized malo-lactic enzyme . No other C4-dicarboxylic acid-decarboxylating enzyme activity could be detected at significant activity in cell-free extracts . In pH-controlled continuous cultures, L . plantarum grew well with glucose as substrate, but not with malate . Addition of lactate to continuous cultures metabolizing glucose or malate decreased cell yields significantly . These results indicate that malo-lactic fermentation by these bacteria can be coupled with energy conservation, and that membrane energetization and ATP synthesis through this metabolic activity are due to malate uptake and/or lactate excretion rather than to an ion-translocating decarboxylase enzyme. Enferm Infecc Microbiol Clin, 1992 Jan, 10(1), 32 - 3 {Endocarditis caused by Lactobacillus}; Urkijo JC et al.; Endocarditis due to Lactobacillus is rare . Its main features were a subacute course and greater difficulties for achieving a complete recovery even using appropriate antimicrobial therapy with serum levels above MIC . We present one case of Lactobacillus endocarditis in a patient with allergy to penicillin, due to a vancomycin-resistant strain . She was successfully treated with clindamycin and gentamicin . We emphasize the need and importance of sensitivity tests and antibiotic tolerance when choosing an optimal treatment for this infection. J Clin Pediatr Dent, 1992 Winter, 16(2), 107 - 11 Lactobacilli from the dentin and saliva in children; Nancy J et al.; Lactobacilli were detected simultaneously in saliva, dental plaque and carious dentinal plaque in 66 children aged 5 to 15 years . The dentinal plaque samples numbered 15 . It was found that Lactobacilli were present in 100% of the dentin samples, 70% of the saliva samples and 29% of the plaque samples . The DMF index and dentinal lactobacilli are systematically linked . The DMF index is weakly linked to salivary and independent of plaque lactobacilli . It is concluded that (1) dentin is responsible for the salivary hypercontamination and (2) the Lactobacillus Count could hardly be a predictive test. Gynecol Obstet Invest, 1992, 34(4), 229 - 33 Effects of chlorhexidine gluconate douche on normal vaginal flora; Shubair M et al.; The effects of a 0.5% aqueous chlorhexidine gluconate (CHG) douche on the normal vaginal flora of twenty healthy nonpregnant volunteers were investigated . The douche was applied in a premeasured 180-ml quantity daily for 7 consecutive days . Specimens for aerobic and anaerobic culture of the vaginal flora were obtained on 3 occasions from each volunteer, once before and twice after CHG use . The culture results were analyzed qualitatively and quantitatively . A blood sample was also collected within 24 h of the last CHG application to determine serum CHG concentration . Lactobacillus spp., Gardnerella vaginalis and Staphylococcus epidermidis were the most prevalent aerobic bacteria at all phases of the study and Bacteroides spp . were the most prevalent anaerobes . The composition of the normal flora was essentially the same 30 days after the last dose as the pretreatment flora . Small amounts of CHG were detected in the serum of all but one subject . No untoward effects on the participants were observed . Candida albicans counts were slightly higher, but prevalence was not significantly increased at the end of the study. Swed Dent J, 1992, 16(6), 253 - 9 Mutans streptococci, lactobacilli and caries prevalence in 15 to 16-year olds in Göteborg . Part II; Kohler B et al.; During the fall of 1987 one hundred and fifty-five 15 to 16-year-olds were examined with regard to caries prevalence, saliva secretion rate and salivary numbers of mutans streptococci and lactobacilli . In 15% of the subjects no mutans streptococci were detected, while 17.7% carried > 10(6) colony forming units (cfu) per ml saliva . The median value was 1.8 x 10(5) cfu per ml saliva . No lactobacilli were detected in 19% of the subjects and 14.3% had > 10(5) cfu per ml saliva . The mean caries prevalence was 21.0, of these 14.1 were incipient lesions . Increased numbers of mutans streptococci and lactobacilli were associated with increasing caries prevalence . Subjects with high numbers of both microorganisms showed about 4 times higher mean caries prevalence than those with low numbers . Streptococcus sobrinus carriers (15%) had both higher mean caries prevalence and a higher proportion of subjects with > 10(6) cfu mutans streptococci per ml saliva than was found in the whole group. Swed Dent J, 1992, 16(6), 231 - 7 Salivary levels of lactobacilli, buffer capacity and salivary flow rate related to caries activity among adults in communities with optimal and low water fluoride concentrations; Wiktorsson AM et al.; In several human studies, scientists have sought to elucidate the connection between caries activity, high levels of lactobacilli, low buffer capacity and a low salivary flow rate, separately or in combinations . The aims of the study were to investigate if there was a difference in caries activity among adults in optimal versus low fluoride areas . It was further investigated if this difference was related to high lactobacilli levels, low buffer capacity and low salivary flow rate, separately or in combination . Finally, it was analysed if the lactobacilli levels were lower in an area with optimal fluoride water concentration . The study is based on clinical examinations of 30-40 year olds who all their lives had drunk water with a fluoride concentration representative for the community . 260 individuals living in the optimal fluoride area and 236 from the low fluoride area are included in the study . The results show a caries activity significantly lower among those in the optimal fluoride area . It is also shown that these differences can not be explained by differences in lactobacilli levels, buffer capacity and salivary flow, neither separately nor in combination . The fluoride concentration in the drinking water is wholly decisive . No difference in lactobacilli levels between optimal and low fluoride areas were demonstrable in this study. Ann Rech Vet, 1992, 23(4), 361 - 70 Heat-killed Lactobacillus acidophilus inhibits adhesion of Escherichia coli B41 to HeLa cells; Fourniat J et al.; Escherichia coli B41 (O101: K99: F41: ST+) adheres to HeLa 229 cells in a diffuse pattern . Heat-killed (100-105 degrees C) Lactobacillus acidophilus (Lacteol strain) was found to inhibit this adhesion in a dose-dependent manner . This inhibitory action was lost after lysis of the L acidophilus, suggesting steric hindrance of E coli adhesion sites rather than competition for a common binding site . A thermostable factor (100-105 degrees C) excreted by L acidophilus into the medium may be required for the adhesion of L acidophilus to HeLa cells, and for the inhibition of adhesion of E coli to these cells. Caries Res, 1992, 26(5), 384 - 90 Caries incidence, mutans streptococci and lactobacilli in irradiated patients during a 12-month preventive programme using chlorhexidine and fluoride; Joyston-Bechal S et al.; Radiotherapy (RT) near salivary glands results in changes in the oral flora in favour of cariogenic organisms and an increased susceptibility to caries . The aim of this study was to assess the effect of a 12-month preventive programme on caries incidence and on the levels of mutans streptococci (ms) and lactobacilli in tongue loop samples taken from patients before, during and after RT . The regime consisted of 2 x daily rinsing with 10 ml 0.2% chlorhexidine, diluted 1:1 with water, for 1 week before RT, during RT and for 4 weeks after RT . This was then substituted with a 0.05% NaF rinse daily . A saliva substitute containing 2 ppm F was used as required . Scaling was carried out before RT and dietary advice and oral hygiene instruction given . Appropriate radiographs were taken at baseline and after 6 and 12 months . Tongue loop samples for microbiology were taken in the middle and end of RT and subsequently at 6, 8, 12, 24, 40 and 52 weeks . Whenever levels of ms exceeded 2 x 10(5) cfu/ml sample, 1% chlorhexidine gel in custom-made applicator trays was applied by the subject for 5 min daily for 14 days . In 25 subjects completing the programme, there was a total of 3 new caries lesions after 12 months . Thirteen pre-existing enamel lesions were arrested . There were significant reductions (p < 0.005) in ms levels from baseline values during RT and 4 weeks after RT . There were no significant increases in ms levels throughout the study.(ABSTRACT TRUNCATED AT 250 WORDS) Urol Int, 1992, 49(3), 125 - 9 Prophylactic effect of a Lactobacillus casei preparation on the recurrence of superficial bladder cancer . BLP Study Group; Aso Y et al.; A randomized controlled study was conducted in patients with superficial bladder cancer in order to investigate the safety of an orally administered (3 g/day) Lactobacillus preparation, biolactis powder (BLP), and its preventive effect on the recurrence after transurethral resection of the bladder tumor (TUR-Bt) . Of 58 cases enrolled in the study 23 cases in the BLP group and 25 cases in the control group completed the study . There were no significant differences in the patient characteristics for the complete cases between the two groups . Comparison of the disease-free duration by the Kaplan-Meier method revealed that the 50% recurrence-free interval after TUR-Bt was prolonged by BLP treatment (350 days) to 1.8 times that in the control group (195 days) . A significant difference between the groups was detected by the long-rank test (p = 0.03) . No adverse side effect was observed . The results suggest that oral administration of BLP is useful for the prevention of the recurrence of superficial bladder cancer. Oncol Res, 1992, 4(6), 249 - 54 Catalysis and ligand binding by thymidylate synthase immobilized on thiopropyl-sepharose 6B; Bradshaw TP et al.; Lactobacillus casei thymidylate synthase, which employs the thiol of cysteine-198 as a covalent catalyst, was reversibly coupled to thiopropyl-Sepharose 6B through the catalytic sulfhydryl group of one of its two subunits, yielding an immobilized heterodimeric form of the enzyme possessing one free active site and one covalently modified active site . Enzyme inactivated by treatment with N-ethylmaleimide, which selectively modifies the active site cysteines but not the remaining cysteines (cys-244), failed to react with the resin . Modified assay procedures were developed and utilized to characterize the activity and ligand binding properties of this unique enzymic species . The immobilized enzyme was found to catalyze thymidylate formation at its free active site but exhibited lowered specific activity (13-fold) and kcat (16-fold) values and an increased Km for dUMP (4-fold) when compared to the native, soluble enzyme . Immobilized enzyme also formed a covalent inhibitory ternary complex with 5-fluoro-2'-deoxyuridylate and 5,10-methylenetetrahydrofolate with a stoichiometry of 0.32 (mol FdUMP: mol enzyme), about half the predicted value of 0.6-0.7 . The results of this initial study suggest that the active sites of the native enzyme dimer are asymmetrical in nature, and that the chemical status of the catalytic sulfhydryl groups may play a key role in directing communication between the subunits. Arch Int Physiol Biochim Biophys, 1992 Jan-Feb, 100(1), 67 - 72 Effect of diet on folates levels and distribution in selected tissues of the rat; Ladjimi H et al.; A technique for the extraction, purification and concentration of folates, followed by high performance liquid chromatography assay with fluorometric detection of the three principal derivatives (tetrahydrofolic, 5-methyl-tetrahydrofolic and formyl-tetrahydrofolic acids) has been applied to the determination of tissue folates in rats . The levels found are compared to those of the microbiological assay using Lactobacillus casei . When rats were fed a diet containing 1 mg of folic acid per kg of food, levels in the intestinal mucosae, liver, whole blood and brain were 0.59, 14.87, 0.28 and 0.83 nmol/g of tissue . An exogenous supply of 200 mg of folic acid/kg of food significantly increased folate levels in all tissues studied, except for the brain: 1.51, 28.93, 0.52 and 0.99 nmol/g, respectively in the above four tissues . The separation of the various derivatives and a variable supply of folic acid have enabled the conversions of these metabolites to be studied. Bioseparation, 1992, 3(2-3), 167 - 75 Enzyme purification by immobilized metal ion affinity partitioning--application to D-hydroxyisocaproate dehydrogenase; Schustolla D et al.; Extraction and purification of D-2-hydroxyisocaproate dehydrogenase from Lactobacillus casei has been studied by means of immobilized metal ion affinity partitioning (IMAP) in aqueous two-phase systems . The partition of the enzyme can be influenced strongly by inclusion of iminodiacetic acid as chelating ligand coupled to polyethylene glycol and loaded with Cu2+ ions into the phase system . This applies to polyethylene glycol/dextran as well as polyethylene glycol/salt phase systems . An increase in enzyme partition coefficient of up to about 1000-fold was observed . Based on the mathematic model presented recently by Suh and Arnold (1990) approximately 6.4 histidine residues were calculated to be involved in the enzyme-metal chelate complex . Direct extraction of the enzyme from both cell homogenate and cell debris supernatant proved unsatisfactory due to disturbances caused by the presence of cell debris and low molecular weight cell components . A combination with a preceding prepurification by a fractional precipitation with polyethylene glycol resulted in a strong affinity effect accompanied by an efficient purification during IMAP (purification factor of 11 with a yield of approximately 90%) . Based on this step, an efficient downstream process can be designed for D-hydroxyisocaproate dehydrogenase. J Chem Technol Biotechnol, 1992, 53(2), 173 - 5 Stability of Lactobacillus bulgaricus immobilized in kappa-carrageenan gels; Buyukgungor H; The future application of immobilized microorganism techniques will depend on the development of systems which are technologically applicable on an industrial scale . These techniques must permit high microbial concentrations and must allow mass transfer to take place with low diffusional limitations . In addition, the mechanical separation of the immobilized microorganisms must be achieved economically . Kappa-carrageenan was used as an ionotropic gel carrier for the immobilization of Lactobacillus bulgaricus (ATCC 11842), and the effects of gel stability on productivity and the rate of product formation were investigated . kappa-carrageenan gels had higher mechanical and chemical stability than alginate gels . The storage stability of microorganisms immobilized in kappa-carrageenan was good enough to retain biocatalytic activity during prolonged storage at 4 degrees C. Acta Microbiol Hung, 1992, 39(3-4), 323 - 5 Adherence of ruminal Streptococcus bovis and Lactobacillus strains to primary and secondary cultures of rumen epithelium; Styriak I et al.; Six strains of rumen Lactobacillus and four Streptococcus bovis strains isolated from rumen wall and fluid samples were examined for the adherence to cells of primary and secondary cultures of ruminal epithelium (REC) prepared from sheep and calf . S . bovis adhered to the keratinized REC . Ruminal lactobacilli did not adhere . The presence of rumen lactobacilli in mixture had no influence on the adherence of S . bovis strains . No difference was observed in the adherence of tested bacteria to epithelial cells of primary or secondary cultures, but adhesion was only detected on keratinized cells. Microbiol Immunol, 1992, 36(11), 1119 - 28 Melibiose transport system in Lactobacillus plantarum; Tamura C et al.; Lactobacillus plantarum ATCC 8014 grew on melibiose at 30 C, but not at 37 C, although it grew on galactose or lactose at either temperature . ATCC 8014 grown on lactose at 30 or 37 C accumulated melibiose slowly, suggesting that melibiose may partly be transported by a lactose transport system . A lactose-negative mutant, NTG 21, derived from ATCC 8014 was isolated . The mutant was totally deficient in lactose transport, but retained normal melibiose transport activity . In NTG 21, the melibiose transport activity was induced by melibiose at 30 C, but not at 37 C . The transport activity itself was found to be stable for at least 3 hr at 37 C, suggesting that the induction process in the cytoplasm rather than the inducer entrance is temperature-sensitive in the organism . The organism also failed to form alpha-galactosidase at 37 C when grown on melibiose . The enzyme synthesis, however, was induced by galactose in NTG 21 (and also by lactose in ATCC 8014) even at 37 C, indicating that the induction of the enzyme is essentially not temperature-sensitive . In NTG 21, melibiose transport system and alpha-galactosidase were induced by galactose, melibiose and o-nitrophenyl-alpha-D-galactopyranoside when the strain was grown at 30 C . Raffinose induced melibiose transport system only a little, while it was a good inducer for alpha-galactosidase . Inhibition studies revealed that galactose may be a weak substrate of the melibiose transport system; no inhibition was demonstrated with lactose and raffinose. J Infect Dis, 1992 Jan, 165(1), 19 - 25 Effects of the spermicidal agent nonoxynol-9 on vaginal microbial flora; Klebanoff SJ; The use of nonoxynol-9--containing vaginal contraceptive preparations increases vaginal (and urethral) colonization by Escherichia coli . Nonoxynol-9 is toxic to various