J Appl Bacteriol, 1996 Mar, 80(3), 338 - 48 Characterization of a proteinaceous antimicrobial produced by Lactobacillus helveticus CNRZ450; Thompson JK et al.; An antimicrobial substance which resembles a bacteriocin was identified in culture supernatant fluids of Lactobacillus helveticus strain CNRZ450 . The bacteriocin was active against a narrow range of strains from closely related species of homofermentative lactobacilli . Its mode of action appeared to be bacteriostatic . Partial purification of the bacteriocin suggested that it was a complex protein with a mol . wt of between 30 and 50 kDa, although there is some evidence that the polypeptide monomer has a mol . wt of around 17 kDa . There was no evidence indicating an extrachromosomal location for its genetic determinant . PCR generated an amplicon from total DNA from strain CNRZ450 using primers based on the helJ gene sequence . A fragment showing homology to this amplicon was located in an EcoRI digest of total DNA from strain CNRZ450 . The pattern obtained was different from that obtained with the helveticin J producer strain NCFB481 . It is possible, therefore, that the antimicrobial from strain CNRZ450 is related to helveticin J at the DNA sequence level although the physical properties of the two antimicrobials reveal several differences. J Appl Bacteriol, 1996 Mar, 80(3), 311 - 8 Purification and characterization of a component produced by Lactobacillus fermentum that inhibits the adhesion of K88 expressing Escherichia coli to porcine ileal mucus; Ouwehand AC et al.; It has previously been shown that Lactobacillus fermentum strain 104r releases compounds into its culture fluid that inhibit the adhesion of enterotoxigenic Escherichia coli K88 . The aim of the present study was to purify and identify this compound . Judged by gel filtration, the compound was found to be approximately 1700 kDa . The amount of active compound increased upon prolonged incubation, while the number of viable cells reduced, suggesting that the activity was coming from dead cells . As the activity can be destroyed by lysozyme treatment and contains glucose, N-acetylglucosamine and galactose, it was concluded that cell wall fragments are the active agent, although cell wall preparations did not have the same effect . Adhesion to some mucus fractions could be inhibited by spent culture fluid, indicating specific interaction between mucus and the active compound . The compound was not able to interfere with the adhesion of E . coli 1107 to neutral lipids from mucus which contain a glycolipid receptor for K88 fimbriae. Lett Appl Microbiol, 1996 Mar, 22(3), 229 - 32 Adhesion of Lactobacillus isolates to intestinal epithelial cells of chicken; Jin LZ et al.; A total of 46 Lactobacillus isolates obtained from chicken intestine were assessed on their ability to adhere to the chicken ileal epithelial cell (IEC) in vitro . Twelve out of the 46 isolates showed moderate to good ability to adhere to the IEC . Temperature (between 4 degrees C and 42 degrees C) did not affect attachment . Incubation (contact) time of 30 min was found to be insufficient for the attachment of bacteria to the IEC, but contact time beyond 1 h did not increase this ability . The pH values (4-7) of the suspending buffer did not have any significant effect on the attachment of bacteria to the IEC, but at pH 8 it was reduced significantly (P < 0.05). Gastroenterol Clin Biol, 1996 Mar, 20(2), 193 - 5 {Liver abscess caused by Lactobacillus acidophilus}; Larvol L et al.; Lactobacillus acidophilus is usually considered to be non pathogenic . We report a case of liver abscess due to Lactobacillus acidophilus in a 39 year-old man with chronic pancreatitis complicated by both endocrine and exocrine insufficiency, and with a choledoco-duodenostomy . Lactobacillus acidophilus was isolated in blood and liver samples . Complete recovery of the liver abscess occurred after antibiotherapy . We suggest that the abnormally low duodenal pH secondary to pancreatic insufficiency may have promoted both Lactobacillus acidophilus adhesion and multiplication in this patient . The choledoco-duodenostomy may then have promoted biliary tract colonisation. Arch Oral Biol, 1996 Mar, 41(3), 271 - 80 Associations between dietary intake, dental caries experience and salivary bacterial levels in 12-year-old English schoolchildren; Beighton D et al.; A population of 328 12-yr-old English schoolchildren, consuming their normal diets, was investigated in a cross-sectional study to determine the interactions between caries experience, oral hygiene status as gingival index (GI), dietary intake (as number of eating events per day and the number of eating events per day at which sugar-containing foodstuffs, confectionery or starch-containing foods were consumed) and salivary levels of caries-associated micro-organisms (mutants streptococci, lactobacilli and yeasts) . The mean (+/- SD) decayed, missing and filled surfaces (DMFS) (excluding precavitation lesions) score was 3.05 +/- 3.85 and 5.72 +/- 5.00 (including precavitation lesions) . The DMFS scores were significantly related to the salivary levels of caries-associated micro-organisms and to the number of eating events per day for total number of eating events and the number of eating events at which sugar-containing foods or confectionery were consumed . These associations were apparent in both bivariate and partial correlation coefficients with the caries-associated micro-organisms and GI controlled . The total daily intakes of food types, except for starch, were not associated with caries experience . No significant correlations were found between intake of food types and salivary levels of caries-associated micro-organisms except that the mean number of confectionery-eating events was correlated with lactobacillus levels (r = 0.136, p < 0.01) . The salivary levels of mutans streptococci, lactobacilli and yeasts were significantly correlated with GI scores . These data do not indicate simple associations between dietary intake, caries and levels of caries-associated micro-organisms . Poor oral hygiene, in children consuming unrestricted diets, may influence the salivary levels of mutans streptococci, lactobacilli and yeasts irrespective of the frequency or amount of sugar consumed . Multiple regression analyses revealed that three variables--GI (probably an indicator of toothbrushing behaviour with a fluoride-containing toothpaste), salivary concentration of lactobacilli and frequency of ingestion of confectionery/sugary foods--were independently and positively related to caries experience. Pediatr Dent, 1996 Mar-Apr, 18(2), 129 - 36 Caries experience and cariogenic markers in HIV-positive children and their siblings; Madigan A et al.; The purpose of this cross-sectional, masked study was to compare the oral status of perinatally HIV-infected children with their uninfected siblings living in the same environment . A secondary purpose was to compare HIV-positive children for differences in oral health with respect to disease advancement . One hundred forty-seven children were examined in their homes and meeting places, using NIH criteria for caries diagnosis . Significant differences were found in the number of caries-free children (P < 0.05), past caries experience (P < 0.003), subsurface demineralizations (P < 0.0001), and caries-related bacteria (P < 0.05) . However, differences in caries prevalence were not found in the 3- to 6-year-old subgroup . Caries prevalence (P < 0.001) and levels of caries-related flora in saliva were correlated to years since diagnosis (mutans streptococci P < 0.008, lactobacilli P < 0.02) . Children with a more advanced disease stage had significantly more caries (P < 0.02) . Among the HIV-infected children, the frequency of carbohydrate intake was clearly correlated to caries (P < 0.003) and to lactobacilli levels (P < 0.0001) . It is concluded that children with perinatally acquired HIV are at greater risk for caries than their siblings, more so with advancing disease. J Infect, 1996 Mar, 32(2), 165 - 7 Lactobacillus rhamnosus infection in a child following bone marrow transplant; Kalima P et al.; We report a case where Lactobacillus rhamnosus was isolated from pericardial effusion and blood in a child following a bone marrow transplant for aplastic anaemia . A resume of cases in which this organism has been implicated as a pathogen is also presented. J Dairy Sci, 1996 Mar, 79(3), 483 - 6 Effect of Lactobacillus acidophilus supplementation of milk replacer on preweaning performance of calves; Cruywagen CW et al.; Forty Holstein-Friesian calves were used to evaluate the effect on young calves of daily dietary supplementation with Lactobacillus acidophilus . Calves were randomly assigned at 2 d of age to one of two treatments; 1) milk replacer with no additives or 2) milk replacer supplemented with 1 ml (5 x 10(7)) of viable L . acidophilus bacteria at each of two feedings per day . Milk replacer was reconstituted to 12% DM and fed at 10% of BW/d for the duration of the 6-wk trial . A commercial starter pellet was offered for ad libitum intake from 7 d of age . Treatment had no effect on actual BW at any stage or on total BW gain; however, average daily gain during wk 2 was affected by L . acidophilus supplementation . Calves receiving L . acidophilus maintained initial BW, and the control calves lost BW until 2 wk of age, at an average rate of 112 g/d . Starter intake, total DMI, feed efficiency, and occurrence of diarrhea were unaffected by treatment . Therefore, L . acidophilus supplementation for calves fed milk replacer may be beneficial during the first 2 wk of life. World J Surg, 1996 Mar-Apr, 20(3), 299 - 307; discussion 307-8 Gut origin sepsis, macrophage function, and oxygen extraction associated with acute pancreatitis in the rat; Wang X et al.; It has been suggested that the gut plays a role in the development of bacterial complications, which are important contributors to morbidity and mortality in patients with acute pancreatitis . The present study evaluated the enteric bacterial translocation, bacterial homeostasis, and reticuloendothelial system function in experimental acute pancreatitis induced by intraductal injection of 5% sodium taurodeoxycholate in the rat . The incidence of bacterial translocation from the gut to mesenteric lymph nodes (MLNs) and lungs significantly increased after 12 hours and to the systemic circulation, ascites, and pancreas at 24 hours . The number of anaerobic bacteria and lactobacilli decreased in the colon and distal ileum from 6 or 12 hours, whereas the number of Escherichia coli increased from 12 hours . The systemic uptake rate of radiolabeled bacteria decreased from 6 hours after induction of acute pancreatitis . The uptake of radiolabeled bacteria by Kupffer cells decreased from 6 hours, whereas the uptake by macrophages from blood, lungs, and the intestine increased . A decrease in macrophage killing capacity was noted, reflected by an increase in the number of cultured viable bacteria from isolated macrophages . The whole-body oxygen extraction rate increased 4 to 24 hours after induction of pancreatitis, whereas the gut oxygen extraction rate decreased at 2 and 4 hours, followed by an increase at 12 to 24 hours . These data show that translocation of enteric bacteria occurs during the early stage of acute pancreatitis and that the MLN-thoracic duct-circulation may be a major route of bacterial dissemination . Compromised gut oxygen metabolism, overexaggerated intestinal macrophages, and impaired host immune function may be involved in the development of infectious complications associated with acute pancreatitis. J Biol Chem, 1996 Feb 9, 271(6), 3079 - 84 Exchange of aspartate and alanine . Mechanism for development of a proton-motive force in bacteria; Abe K et al.; We examined the idea that aspartate metabolism by Lactobacillus subsp . M3 is organized as a proton-motive metabolic cycle by using reconstitution to monitor the activity of the carrier, termed AspT, expected to carry out the electrogenic exchange of precursor (aspartate) and product (alanine) . Membranes of Lactobacillus subsp . M3 were extracted with 1.25% octyl glucoside in the presence of 0 . 4% Escherichia coli phospholipid and 20% glycerol . The extracts were then used to prepare proteoliposomes loaded with either aspartate or alanine . Aspartate-loaded proteoliposomes accumulated external {3H}aspartate by exchange with internal substrate; this homologous self-exchange (Kt = 0.4 mm) was insensitive to potassium or proton ionophores and was unaffected by the presence or absence of Na+, K+, or Mg2+ . Alanine-loaded proteoliposomes also took up {3H}aspartate in a heterologous antiport reaction that was stimulated or inhibited by an inside-positive or inside-negative membrane potential, respectively . Several lines of evidence suggest that these homologous and heterologous exchange reactions were catalyzed by the same functional unit . Thus, {3H}aspartate taken up by AspT during self-exchange was released by a delayed addition of alanine . In addition, the spontaneous loss of AspT activity that occurs when a detergent extract is held at 37 degrees C prior to reconstitution was prevented by the presence of either aspartate (KD(aspartate) = 0.3 mm) or alanine (KD(alanine) > or = 10 mm), indicating that both substrates interact directly with AspT . These findings are consistent with operation of a proton-motive metabolic cycle during aspartate metabolism by Lactobacillus subsp . M3. Biosci Biotechnol Biochem, 1996 Feb, 60(2), 333 - 4 Relative activity of N-(beta-D-glucopyranosyl)nicotinic acid to nicotinic acid as a niacin nutrient in rats and in Lactobacillus plantarum ATCC 8014; Nishitani H et al.; We investigated the relative activity of N-(beta-D-glucopyranosyl)-nicotinic acid as a niacin nutrient in rats and in Lactobacillus plantarum ATCC 8014 . N-(beta-D-Glucopyranosyl)-nicotinic acid is a detoxified product or storage form of nicotinic acid that is found in plants . The relative activity of N-(beta-D-glucopyranosyl)nicotinic acid to nicotinic acid in rats was 1/2.3, 1/2.2, 1/1.0, and 1/1.7 as indices of the body weight gain, food intake, blood NAD content, and the increased urinary excretion of niacin and its metabolites, respectively . N-(beta-D-Glucopyranosyl)nicotinic acid had no niacin activity in Lactobacillus plantarum ATCC 8014. FEMS Microbiol Lett, 1996 Feb 1, 136(1), 63 - 9 Characterization of pepR1, a gene coding for a potential transcriptional regulator of Lactobacillus delbrueckii subsp . lactis DSM7290; Stucky K et al.; The gene designated pepR1, encoding a potential transcription regulator of Lactobacillus delbrueckii subsp . lactis DSM7290, was identified by sequence similarity of an open reading frame located upstream of the prolidase pepQ orientated in opposite direction . pepQ and pepR1 coding regions are spaced by 152 nucleotides . Upstream of the -35 region of pepQ, a 14-bp palindromic sequence, homologous to the catabolite responsive element, could be identified . The pepRl gene has the potential to encode a protein of 333 amino acids with a calculated molecular mass of 36955 Da and a calculated pl of 5.5 . The deduced protein sequence shows significant identity to the catabolite control protein of Bacillus . Co-expression in Escherichia coli was studied with the pepR1-pepQ intergenic region fused to the promoterless beta-galactosidase reporter gene . The pepQ-beta-galactosidase hybrid displayed an enhanced expression in the presence of cloned pepR1. Appl Microbiol Biotechnol, 1996 Feb, 44(6), 766 - 73 DNA sequence analysis, expression, distribution, and physiological role of the Xaa-prolyldipeptidyl aminopeptidase gene from Lactobacillus helveticus CNRZ32; Yuksel GU et al.; Lactobacillus helveticus CNRZ32 possesses an Xaa-prolyldipeptidyl aminopeptidase (PepX), which releases amino-terminal dipeptides from peptides containing proline residues in the penultimate position . The PepX gene, designated pepX, from Lb . helveticus CNRZ32 was sequenced . Analysis of the sequence identified a putative 2379-bp pepX open-reading frame, which encodes a polypeptide of 793 amino acid residues with a deduced molecular mass of 88,111 Da . The gene shows significant sequence identity with sequenced pepX genes from lactic acid bacteria . The product of the gene contains a motif that is almost identical with the active-site motif of the serine-dependent PepX from lactococci . The introduction of pepX into Lactococcus lactis LM0230 on either pGK12 (a low-copy-number plasmid vector) or pIL253 (a high-copy-number plasmid vector) did not result in a significant increase in PepX activity, while the introduction of pepX into CNRZ32 on pGK12 resulted in a four-fold increase in PepX activity . Southern hybridization experiments revealed that the pepX gene from CNRZ32 is well conserved in lactobacilli, pediococci and streptococci . The physiological role of PepX during growth in lactobacillus MRS (a rich medium containing protein hydrolysates along with other ingredients) and milk was examined by comparing growth of CNRZ32 and a CNRZ32 PepX-negative derivative . No difference in growth rate or acid production was observed between CNRZ32 and its PepX-negative derivative in MRS . However, the CNRZ32 PepX-negative derivative grew in milk at a reduced specific growth rate when compared to wild-type CNRZ32 . Introduction of the cloned PepX determinant into the CNRZ32 PepX-negative derivative resulted in a construct with a specific growth rate similar to that of wild-type CNRZ32. Int J Food Microbiol, 1996 Feb, 29(1), 105 - 9 Characterization of Lactobacillus acidophilus strains for use as dietary adjunct; Gupta PK et al.; Seven Lactobacillus acidophilus strains were studied for their morphology, biochemical properties, growth behaviour, bile tolerance, cholesterol uptake and survival at low pH . The strains significantly differed in their biochemical and beneficial traits . The strains which exhibited cholesterol uptake and ability to grow in the presence of 0.3% bile salt also utilized mannitol. Int J Food Microbiol, 1996 Feb, 29(1), 93 - 104 A rapid mechanical lysing procedure for routine analysis of plasmids from lactobacilli, isolated from sourdoughs; Reinkemeier M et al.; Variations in cell wall composition of lactobacilli complicate attempts to standardize plasmid detection on the basis of enzymatic lysing procedures . Mechanical disruption of cell walls by a horizontal mixer-mill proved to be more effective, rapid and reproducible . In order to judge the risk of damaging plasmid deoxyribonucleic acids (DNA) in this way, plasmid profiles obtained after enzymatic lysing and mechanical disruption of cell walls were compared . As no differences were detected the mechanical procedure was accepted as a suitable method for routine analysis of plasmid profiles. Int J Food Microbiol, 1996 Feb, 29(1), 49 - 58 Microbiology of mesu, a traditional fermented bamboo shoot product; Tamang JP et al.; The use of mesu as a pickle and as the base of curry is a tradition in the Darjeeling hills and Sikkim of India . A total of 327 strains of lactic acid bacteria, representing Lactobacillus plantarum, L . brevis and Pediococcus pentosaceus were isolated from 30 samples of mesu . These species were present in all samples of raw bamboo shoots tested . Mesu was dominated by L . plantarum followed by L . brevis; P . pentosaceus was isolated less frequently and recovered from only 40-50% of the mesu samples . The fermentation was initiated by P . pentosaceus, followed by L . brevis, and finally succeeded by L . plantarum species . During fermentation, the titratable acidity increased from 0.04 to 0.95%, resulting in the decline in pH from 6.4 to 3.8. J Dairy Sci, 1996 Feb, 79(2), 212 - 9 Viability of Lactobacillus acidophilus and Lactobacillus casei in fermented milk products during refrigerated storage; Nighswonger BD et al.; The viability was investigated of five strains of Lactobacillus acidophilus and one strain of Lactobacillus casei that were added as adjuncts to yogurt and cultured buttermilk during 28 d of refrigerated storage at 5 to 7 degrees C . A modification of LBS (Lactobacillus selection) agar was used for the enumeration of L . acidophilus and L . casei . The medium allowed the colony formation of the adjunct bacteria while preventing colony formation of the traditional yogurt or buttermilk starter cultures . At each sampling period, colonies from the selective agar medium were isolated for confirmation of identity to confirm that only L . acidophilus and L . casei were enumerated, that their characteristics did not change during storage, or both . The strains of L . acidophilus varied in both cultured products . In buttermilk, L . acidophilus MUH-41, O-16, and L-1 exhibited no significant loss in viability, but strains 43121 and La-5 did . No significant loss in viability of L . acidophilus MUH-41 and L-1 occurred in yogurt prepared using culture CM2; however, strains 43121, O-16, and La-5 lost viability . In the yogurt prepared using culture YC-4, L . acidophilus 43121 exhibited no significant loss in viability, but MUH-41, O-16, L-1, and La-5 did . There was no loss in viability of L . casei GG during storage of any of the cultured products. J Anim Sci, 1996 Feb, 74(2), 447 - 56 Comparative assessment of bacterial inoculation and propionic acid treatment of aerobic stability and microbial populations of ensiled high-moisture ear corn; Sebastian S et al.; High-moisture ear corn (HMEC) was untreated, treated with propionic acid (PA), or inoculated with a mixture of Lactobacillus plantarum and Enterococcus faecium and allowed to ensile in laboratory silos for 0, 7, 21, 42, 138, or 202 d . The silages were evaluated for fermentation quality, microbial populations, and aerobic stability . In all treatments, silage pH declined rapidly within 7 d, but the rate of decline seemed greatest with the inoculum . The lactic acid content of inoculated HMEC was higher (P < .05) than that of control of PA-treated HMEC . Regardless of treatment, the population of lactic acid bacteria (LAB) increased (P < .1) up to 7 to 21 d of fermentation then declined; LAB counts decreased (P < .05) up to 42 d in control and PA-treated silage but continued to decline until 138 d for inoculated silage . Yeast and mold counts tended to decrease up to 42 d of ensiling then decreased (P < .05) as fermentation progressed . Between 138 and 202 d of ensiling, the control silage showed a marked increase (P < .10) in pH and yeast and mold populations, providing evidence of secondary fermentation; PA treatment and bacterial inoculation prevented secondary fermentation . Inoculation tended to reduce estimates of sample temperature for silage stored for 138 d and exposed to air, but not for the corresponding silage stored for 202 d . Treatment with PA prevented the loss (P > .05) of acetic acid and the rise (P > .05) in pH during air exposure of the 138-d silage; both control and PA-treated silage showed an increase (P < .05) in yeast and mold populations, but the increments were 38% and 23%, respectively . Compared with PA, the relative efficacy of inoculation in improving aerobic spoilage of HMEC depended on the period of silo storage and the criterion used to assess aerobic stability. Urol Clin North Am, 1996 Feb, 23(1), 43 - 54 Bacteriuria and urinary infections in the elderly; Childs SJ et al.; Aging is associated with a decreased physiological functioning, reflecting the body's progressive inability to maintain homeostasis as age increases . The physiologic dysfunctions experienced in response to the aging process increase the individual's susceptibility to infection . Many elderly subjects are hospitalized for the care and treatment of functional disabilities; thus, an increased exposure to possible uropathogens (many with antimicrobial resistance) often results in infection . Additionally, indwelling catheters and other attending procedures may provide a microenvironment conducive to infection . In catheterized patients, the drainage bag often is infected with polymicrobes, which enhances the transference of antimicrobial genetic information . Postmenopause reflects a decrease in circulating estrogen, and a relational decrease in lactobacilli colonization with a lower vaginal pH . Consequently, vaginal colonization with possible uropathogenic and gastrointestinal bacteria increases, which partially may account for the generally higher incidence of bacteriuria in elderly women as opposed to elderly men . Urinary infections in the elderly more commonly are asymptomatic . Treatment for asymptomatic bacteriuria is not justified and will often present opportunities for the infecting organism to acquire antimicrobial resistance . Only symptomatic bacteriuria presenting adverse conditions in the host should be treated . Antimicrobial selection for the treatment of complicating symptomatic urinary infections in elderly subjects is complicated by the many physiological and environmental conditions associated with older age patients . Unfortunately, data confirming the efficacy and safety of antimicrobial agents for the treatment of symptomatic infections in the elderly presently are insufficient. J Appl Bacteriol, 1996 Feb, 80(2), 138 - 46 Influence of pH, temperature and initial yeast:bacteria ratio on the stimulation of Lactobacillus hilgardii by Saccharomyces florentinus isolated from sugary kefir grains; Leroi F et al.; The effects of pH, temperature and initial yeast:bacteria ratio on Lactobacillus hilgardii and Saccharomyces florentinus cultivated either in pure or mixed culture were studied . Quadratic polynomial as a function of factors was proposed to express the lactic acid production at different sampling times, and the percentage increase in lactic acid production by Lact . hilgardii in mixed culture compared with pure culture . Temperature was the factor which had the main influence on lactic acid production in mixed culture, whereas stimulation of bacteria depended greatly on pH value . In the range 0.1-20%, the initial yeast-bacteria ratio had no effect on these responses, but presence of the yeast was absolutely necessary to obtain high production of lactic acid . Optimum culture conditions were determined to maximize these characteristics. Acta Chir Belg, 1996 Feb, 96(1), 44 - 8 The role of lactulose in the prevention of bacterial translocation in surgical trauma; Ozcelik MF et al.; Surgical trauma (ST) is one of the causative factor of bacterial translocation . In this study we investigated the prevention of bacterial translocation with lactulose in a surgical trauma model . The study was designed in 3 experimental groups consisting of 15 rats in each . Group 1 was sham operated controls, group 2 was ST + physiologic saline treated and group 3 was ST + lactulose treated animals . Lactulose and physiologic saline were given by oro-gastric intubation in a dose of 2 ml of 33.5% solution/d and 2 ml/d respectively starting 3 days prior to surgery . Bacterial translocation was investigated 48 hours after the operations . In sham operated controls only 1 bacterial translocation to the mesenteric lymph nodes (MLN) was observed . In the ST + physiologic saline treated group bacterial translocation to the MLN and portal venous blood (PVB) were significantly increased compared with both sham operated controls and the ST + lactulose treated group (p < 0.001) . In rats with lactulose treatment the results of caecal bacterial counts showed a significant decrease in the number of gram-negative aerobes and facultative anaerobe bacteria (p < 0.01) and a significant increase in the number of lactobacilli (p < 0.001) compared to the sham operated controls . Measurement of the mucosal height showed a significant increase at the terminal ileum and the caecum compared with the sham operated controls and the surgical trauma+physiologic saline treated group (p < 0.001) . We conclude that oral lactulose treatment 3 days prior to the surgical trauma, reduced the incidence of bacterial translocation to the MLN and PVB. J Bacteriol, 1996 Feb, 178(3), 701 - 4 Sequencing, distribution, and inactivation of the dipeptidase A gene (pepDA) from Lactobacillus helveticus CNRZ32; Dudley EG et al.; Previously, the gene for a general dipeptidase (pepDA) was isolated from a gene bank of Lactobacillus helveticus CNRZ32 . The pepDA gene consists of a 1,422-bp open reading frame which could encode a polypeptide of 53.5 kDa . No significant identity was found between the deduced amino acid sequence of the pepDA product and the sequence for other polypeptides reported in GenBank . Southern hybridization studies with a pepDA probe indicated that the nucleotide sequence for pepDA is not well conserved among a variety of lactic acid bacteria . Growth studies indicated that a pepDA deletion had no detectable effect on growth rate or acid production by L . helveticus CNRZ32 in milk . Furthermore, no difference in total cellular dipeptidase activity was detected between the mutant and wild-type strains during logarithmic growth in MRS medium. J Bacteriol, 1996 Feb, 178(3), 575 - 82 Osmotic regulation of intracellular solute pools in Lactobacillus plantarum; Glaasker E et al.; Bacteria respond to changes in medium osmolarity by varying the concentrations of specific solutes in order to maintain constant turgor pressure . The cytoplasmic pools of K+, proline, glutamate, alanine, and glycine of Lactobacillus plantarum ATCC 14917 increased when the osmolarity of the growth media was raised from 0.20 to 1.51 osmol/kg by KCL . When glycine-betaine was present in a high-osmolarity chemically defined medium, it was accumulated to a high cytoplasmic concentration, while the concentrations of most other osmotically important solutes decreased . These observations, together with the effects of glycine-betaine on the specific growth rate under high-osmolarity conditions, suggest that glycine-betaine is preferentially accumulated in L . plantarum . Uptake of glycine-betaine, proline, glutamate, and alanine was studied in cells that were alternately exposed to hyper- and hypo-osmotic stresses . The rate of uptake of proline and glycine-betaine increased instantaneously upon increasing the osmolarity, whereas that of other amino acids did not . This activation occurred also under conditions in which protein synthesis was inhibited was most pronounced when cells were pregrown at high osmolarity . The duration of net transport was a function of the osmotic strength of the assay medium . Glutamate uptake was not activated by an osmotic upshock, and the uptake of alanine was low under all conditions tested . When cells were subjected to osmotic downshock, a rapid efflux of accumulated glycine-betaine, proline, and alanine occurred whereas the pools of other amin acids remained unaffected . The results indicate that osmolyte efflux is, at least to some extent, mediated via specific osmotically regulated efflux systems and not via nonspecific mechanisms as has been suggested previously. J Biotechnol, 1996 Jan 26, 44(1-3), 183 - 92 The potential of Lactobacillus as a carrier for oral immunization: development and preliminary characterization of vector systems for targeted delivery of antigens; Pouwels PH et al.; Oral administration of lactobacilli evokes mucosal and systemic immune responses against epitopes associated with these organisms (Gerritse et al., 1990, 1991) . The adjuvant function of different Lactobacillus species was investigated under the conditions of intraperitoneal (i.p.) injection or oral administration . After i.p . injection of trinitrophenylated chicken gamma-globulin, high DTH responses were observed with Lactobacillus casei and Lactobacillus plantarum, but low responses with Lactobacillus fermentum and Lactobacillus delbrueckii subsp . bulgaricus . In different experimental model systems L . casei and L . plantarum consistently showed significant adjuvanticity . A series of expression and expression-secretion vectors containing the strong constitutive promoter of the L . casei L-ldh gene or the regulatable promoter of the Lactobacillus amylovorus amy gene (Pouwels and Leer, 1995) was used for the intracellular, extracellular and surface-bound expression of an influenza virus antigenic determinant fused to Escherichia coli beta-glucuronidase . Intracellular expression of the fusion protein amounted to 1-2% of total soluble protein . Lactobacilli synthesizing the fusion protein intracellularly evoked an oral immune response after subcutaneous priming. J Mol Biol, 1996 Jan 26, 255(3), 522 - 35 Entropy in bi-substrate enzymes: proposed role of an alternate site in chaperoning substrate into, and products out of, thymidylate synthase; Birdsall DL et al.; Three steps along the pathway of binding, orientation of substrates and release of products are revealed by X-ray crystallographic structures of ternary complexes of the wild-type Lactobacillus casei thymidylate synthase enzyme . Each complex was formed by diffusion of either the cofactor 5,10-methylene-5,6,7,8-tetrahydrofolate or the folate analog 10-propargyl-5,8-dideazafolate into binary co-crystals of thymidylate synthase with 2'-deoxyuridine-5'-monophosphate . A two-substrate/enzyme complex is formed where the substrates remain unaltered . The imidazolidine ring is unopened and the pterin of the 5,10-methylene-5,6,7,8-tetrahydrofolate cofactor binds at an unproductive "alternate" site . We propose that the presence of the pterin at this site may represent an initial interaction with the enzyme that precedes all catalytic events . The structure of the 2'-deoxyuridine-5'-monophosphate and 10-propargyl-5,8-dideazafolate folate analog complex identifies both ligands in orientations favorable for the initiation of catalysis and resembles the productive complex . A product complex where the ligands have been converted into products of the thymidylate synthase reaction within the crystal, 2'-deoxythymidine-5'-monophosphate and 7,8-dihydrofolate, shows how ligands are situated within the enzyme after catalysis and on the way to product release. Science, 1996 Jan 26, 271(5248), 477 - 81 Thiyl radicals in ribonucleotide reductases; Licht S et al.; The ribonucleoside triphosphate reductase (RTPR) from Lactobacillus leichmannii catalyzes adenosylcobalamin (AdoCbl)-dependent nucleotide reduction, as well as exchange of the 5' hydrogens of AdoCbl with solvent . A protein-based thiyl radical is proposed as an intermediate in both of these processes . In the presence of RTPR containing specifically deuterated cysteine residues, the electron paramagnetic resonance (EPR) spectrum of an intermediate in the exchange reaction and the reduction reaction, trapped by rapid freeze quench techniques, exhibits narrowed hyperfine features relative to the corresponding unlabeled RTPR . The spectrum was interpreted to represent a thiyl radical coupled to cob(II)alamin . Another proposed intermediate, 5'-deoxyadenosine, was detected by rapid acid quench techniques . Similarities in mechanism between RTPR and the Escherichia coli ribonucleotide reductase suggest that both enzymes require a thiyl radical for catalysis. Eur J Biochem, 1996 Jan 15, 235(1-2), 262 - 6 31P solid-state NMR measurements used to detect interactions between NADPH and water and to determine the ionisation state of NADPH in a protein-ligand complex subjected to low-level hydration; Gerothanassis IP et al.; 31P-NMR spectra of NADPH and NADPH bound to Lactobacillus casei dihydrofolate reductase have been recorded using the techniques of cross-polarization, magic-angle spinning and high-power proton-decoupling on both lyophilized and hydrated samples . Previous studies on the lyophilized complex of L . casei dihydrofolate reductase with NADPH and methotrexate, measuring the isotropic shifts and principal components of the chemical shift tensors, have shown that the 2'-phosphate group of bound NADPH exists as a mixture of the dianionic and monoanionic states {Gerothanassis, I . P, Barrie, P . J., Birdsall, B . & Feeney, J . (1994) Eur J . Biochem . 226, 211-218} . In the present study on hydrated samples, the characterization of the isotropic shift and chemical shift tensors of the 2'-phosphate signal indicates that the 2'-phosphate is almost exclusively in the dianionic state . This is in agreement with earlier 31P-NMR studies in solution {Feeney, J., Birdsall, B., Roberts, G . C . K . & Burgen, A . S . V . (1975) Nature 257, 564-566} . In experiments examining progressively hydrated (6%, 12%, 15%, by mass) samples, the observed signals become increasingly narrower probably because the microenvironments of the 31P nuclei become more homogeneous upon sample hydration . Chemical exchange between mobile water molecules and bound protons close to individual sites on NADPH has been indirectly monitored on a hydrated sample (15% water, by mass) using a pulse sequence proposed by Harbison and coworkers {Harbison, G . S., Roberts, J . E., Herzfeld, J . & Griffin, R . G . (1988) J . Am . Chem . Soc . 110, 7221-7223} . In this experiment, the two diphosphate signals are totally suppressed while the 2'-phosphate phosphorus signal remains: this indicates a significant polarization of the 2'-phosphate nuclei from protons in exchange with those of mobile water molecules. Biochemistry, 1996 Jan 9, 35(1), 348 - 60 EPR polarization studies on Mn catalase from Lactobacillus plantarum; Meier AE et al.; The binuclear manganese active site of Mn catalase catalyzes redox disproportionation of hydrogen peroxide, forming dioxygen and water . We report here multifrequency EPR and microwave polarization studies of the catalytically active homovalent Mn2+ complex of Lactobacillus plantarum Mn catalase, resolving spectra from each of the thermally accessible multiplet states of the coupled complex by multivariate methods . The experimental spectra have been simulated using computational approaches for the binuclear cluster to predict both intensity and polarization for arbitrary values of the ground state parameters . These two spectroscopic properties define the nature of the ground state wavefunctions and so serve as a sensitive and quantitative measure of the inter-ion interactions in the reduced complex . Interpretation of the spectra in terms of a pair Hamiltonian that includes Heisenberg exchange, dipolar, single site zero field splitting, and Zeeman perturbations leads to the most complete ground state description of the active site metal centers . The results of this spectroscopic analysis support a picture of two high spin ions weakly coupled by exchange interactions (J = 40 cm-1) with relatively small dipole-dipole coupling and single site zero field splittings for the ligand-free reduced enzyme . The coupling between fluoride binding and protonation of the complex has been demonstrated by proton uptake studies . The binding of two fluoride ions in the active site dramatically changes the pair spectra, reflecting a substantially reduced J-coupling (J = 10.5 cm-1) that must be a consequence of perturbation of the bridging ligands . Anion binding to the binuclear Mn complex appears to result in poisoning of the active site by protons, possibly associated with insertion of fluoride into bridging positions of the dimanganese core. Microb Drug Resist, 1996 Winter, 2(4), 415 - 21 Persistence of vancomycin-resistant Enterococcus faecium gastrointestinal tract colonization in antibiotic-treated mice; Dever LL et al.; Colonization with vancomycin-resistant Enterococcus faecium (VREF) is strongly associated with previous antimicrobial therapy . The gastrointestinal (GI) tract appears to be the major reservoir for this organism . We used antibiotic-treated Swiss Webster mice to study GI tract colonization with a characterized strain of VREF (E . faecium 228) . Mice were pretreated with antibiotics in their daily drinking water and inoculated with 10(9) colony-forming units (CFU) of E . faecium 228 by oral gavage . We were able to establish persistent colonization with high concentrations of E . faecium 228 (> 8.0 log10 CFU/g of feces) in animals treated with 5 mg/ml of streptomycin plus 1 mg/ml of cefotetan . RP 59500, a streptogramin antibiotic with good in vitro activity against VREF, was administered orally in mice (n = 8) colonized with E . faecium 228 . After 14 days of treatment VREF was undetectable in feces of all treated mice (< 3.0 CFU/g) . Seven days after discontinuation of RP 59500, VREF was present in the feces of all animals . VREF isolates recovered after treatment remained susceptible to RP 59500 . Attempts to eradicate E . faecium 228 colonization by oral administration of a vancomycin-sensitive E . faecium strain (SF68) or Lactobacillus spp . were unsuccessful as long as animals continued to receive streptomycin and cefotetan . Recovery of E . faecium 228 from cultures of livers and gallbladders in some animals with persistent GI tract colonization suggests that the organisms may also colonize the hepatobiliary system. Folia Microbiol (Praha), 1996, 41(2), 130 - 6 Bacteriocins of Lactobacillus plantarum strains from fermented foods; Olasupo NA; Bacteriocin-producing strains may be used as protective cultures to improve the microbial safety of foods . The crude or purified form of these antimicrobial agents may also be applied directly as food preservative . This review gives survey of the different bacteriocins produced by Lactobacillus plantarum isolated from fermented food products with particular emphasis on their genetic and biochemical properties . A number of bacteriocins are produced by L . plantarum . These include plantaricin B, plantaricin BN, plantaricin A, plantaricin C, plantaricin S and T, plantaricin F, plantaricin C19 and SA6 and other unnamed bacteriocins . However, with the exception of plantaricin A, information on the genetic and biochemical characteristics of L . plantarum bacteriocins is still scant. Folia Microbiol (Praha), 1996, 41(4), 333 - 8 Attachment of lactic acid bacteria to beef-muscle surfaces; Benito Y et al.; The effect of immersion time and cell concentration in the attachment of several lactic acid bacteria with antibacterial activity to beef-muscle surface was studied . The number of firmly attached bacteria increased with immersion time in the case of Pediococcus acidilacti, Lactobacillus sake, Lactococcus cremoris (two strains) and Pediococcus acidilacti . Pediococcus pentosaceus, Lactococcus lactis and Lactobacillus curvatus reached maximum adhesion after 15-30 min . The highest strength of attachment (Sr values) were observed after 15-30 min of contact time except for P . pentosaceus . For all strains, the number of bacteria adhering to meat increased with increasing cell concentration in the adhesion medium . The highest strength of attachment was observed at a cell concentration of 10(5)/mL mainly for L . sake, L . lactis and L . cremoris . Due to their attachment characteristics, L . sake, L . lactis and L . cremoris are proposed as potential biocontrol agents because they could grow on meat surface and limit the potential attachment of pathogenic microorganisms. Scand J Infect Dis, 1996, 28(6), 559 - 62 Rapid antigen tests for Neisseria gonorrhoeae and Chlamydia trachomatis are not accurate for screening women with disturbed vaginal lactobacillary flora; Donders GG et al.; We studied the accuracy of the rapid antigen detection tests Gonozyme and Chlamydiazyme in high-risk women in an outpatient prenatal clinic, Kalafong University Hospital, Pretoria, South Africa . Women (n = 433) presenting with uneventful pregnancy (n = 324), unavoidable miscarriage (n = 41) or infertility of 1 year's duration (n = 68) had a Pap smear for lactobacillary grading and detection of pathogens like Candida albicans or Trichomonas vaginalis, a swab for culture of Neisseria gonorrhoeae, and a swab for Gonozyme, Chlamydiazyme and Chlamydia immunofluorescence collected from the endocervix . Specificities of both antigen tests were high, but sensitivities and positive predictive values were disappointingly low . Chlamydial antigen was recovered in only 37% of samples with positive immunofluorescence, gonococcal antigen was detected in only 50% of samples with positive culture for N . gonorrhoeae . Although prevalence of N . gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis was higher in women with disturbed lactobacillary grades on the Pap smears, sensitivities of the antigen tests were lower in this group . We conclude that detection of endocervical antigens of C . trachomatis and N . gonorrhoeae lacked sensitivity in pregnant and infertile women living in an area with high prevalence of chlamydial cervicitis, gonorrhoea and Trichomonas vaginitis . Furthermore, the rapid antigen tests lack accuracy when the lactobacillary flora is disturbed and are, therefore, not suitable for detection of C . trachomatis or N . gonorrhoeae in pre-screened patients. Akush Ginekol (Sofiia), 1996, 35(3), 37 - 9 {The bacterial vaginosis problem . II . The microbiology of bacterial vaginosis}; Shopova E et al.; Microbial species in the vaginal content of healthy woman in her reproductive age were described, as well as the importance of hydrogen peroxide (H2O2) producing Lactobacillus spp . The characteristics of the basic microbial species associated with the BV was presented . Discussed were the various possible methods for BV diagnosing . The coloured microscopic preparation was accepted and applied as the main one in the routine practice. Medicina (B Aires), 1996, 56(3), 284 - 6 {Native-valve endocarditis produced by Lactobacillus casei sub . rhamnosus refractory to antimicrobial therapy}; Monterisi A et al.; Lactobacillus endocarditis is a rare infection . In fact, only 42 cases have been described in the literature from 1938 up to date . In only 17 previously reported cases have patients been cured with medical therapy alone . Although infections produced by Lactobacillus spp, have been described in our country, none of them included endocarditis . We report herein a case of endocarditis due to a vancomycin-resistant strain of Lactobacillus casei sub . rhamnosus in a 29-year-old man with prolapse of the mitral valve . He required surgical replacement of his valve because of the poor response to antimicrobial therapy with penicillin and gentamicin . The patient displayed a successful clinical outcome, with no evidence of recurrence along the subsequent 2 years . We point out the need to accurately identify Lactobacillus spp . in isolates from blood cultures of patients with endocarditis, since these bacteria may often be mistaken for other species more frequently associated to this infection, which usually respond to conventional antimicrobial therapy . Furthermore, we suggest that early surgical replacement should be considered when lactobacillus endocarditis is diagnosed. Antibiot Khimioter, 1996, 41(10), 16 - 8 {Change in various biological properties of Lactobacillus as affected by ribonuclease}; Kolpakov AI et al.; The influence of RNAse from Bacillus intermedius on the growth of the industrial strain Lactobacillus plantarum 8R-A3 was studied . It was shown that the stimulating effect of the enzyme depended on its dose and manifested itself in decreasing the growth lag phase . At the same time the growth stimulating dose of RNAse increased the Lactobacillus adhesion to the epithelial cells and promoted secretion of proteinases from Lactobacillus to the culture medium . The possible use of RNAse as a stimulant of the growth of industrial strains was demonstrated which is advantageous for colonization of the biological surfaces. Rev Assoc Med Bras, 1996 Jan-Mar, 42(1), 11 - 5 {Preliminary study on low-trait genital infection and cervical epithelial dysplasia in women from the Parakanä tribe of South America}; Brito EB et al.; BACKGROUND: We evaluated the occurrence of low-trait genital infection and cervical epithelial dysplasia in women from a South-american indian tribe in the Brazilian Amazonia . METHODS: Cross-sectional study of women older than 10 years from two indian settlements of the Parakana tribe: Paranatinga and Maroxewara . Demographic data and information about sexual behavior as well as obstetric/gynaecological history were recorded . Two gynecologists examined 80 patients (89.9%), and collected vaginal and cervical specimens of 69 indians for further laboratory analysis, by Gram stain and Papanicolaou method . Fourteen (20.3%) women resulted to be pregnant . RESULTS: Parakana women begin sexual activity early, after menarche; they have multiple sexual partners; are multiparous . Some of his partners already had intercourse with women of our society . In Paranatinga, vaginal discharges were a very frequent sign and not age-related, and women presented high frequency of disturbances on lactobacilli flora, greater than among inhabitants of Maroxewara . Pap smears in 91.5% of all patients showed inflammatory pattern . When found an possible etiologic agent (61.3%), in 63.4% it was Gardnerella vaginalis, in 7.3% Trichomonas vaginalis and in 4.9% Candida sp . In 23.2% of smears cythophatic signs related to infection by human papillomavirus were identified . One case had morphological changes compatible with cervical intraepithelial neoplasia grade I, another with CIN II and, in a 48 year old indian, cervical cancer . CONCLUSIONS: Near all women had some grade of cervical disease . Measure HPV-infection prevalence among Parakana indians with adequate methods may improve our understanding about worldwide occurrence of HPV infections . Established risk factors for cancer of the cervix and sexually transmitted diseases were common in this tribe. Crit Rev Oral Biol Med, 1996, 7(3), 259 - 77 Potential of diagnostic microbiology for treatment and prognosis of dental caries and periodontal diseases; Baehni PC et al.; Most evidence suggests that only a finite number of bacteria are responsible for dental caries and periodontal diseases . This knowledge led to the development of microbial tests which can identify suspected pathogens . Current evaluation of the diagnostic power of microbial tests has shown that they have a low sensitivity and a low prognostic value . Despite these shortcomings, there are valid indications for microbiological-based diagnosis . Salivary microbial tests for the detection of mutans streptococci and lactobacilli may be useful, for example, in young children, oligosialic patients, and orthodontic patients . These tests can be used to monitor the success of chemopreventive measures or compliance with dietary recommendations . Microbial diagnosis, may also be valuable in the treatment of early-onset periodontitis or in subjects who respond poorly to periodontal therapy . The use of microbial tests to monitor the efficacy of chemotherapy or mechanical treatment is of particular interest. Ann Nutr Metab, 1996, 40(3), 137 - 45 Promotion of IgA immune response in patients with Crohn's disease by oral bacteriotherapy with Lactobacillus GG; Malin M et al.; The effect of oral bacteriotherapy with human Lactobacillus casei strain GG (10(10) colony-forming units twice daily for 10 days) was investigated in Crohn's disease and in juvenile chronic arthritis which are chronic inflammatory diseases associated with impaired mucosal barrier function . During oral bacteriotherapy, the gut immune response was indirectly assessed by solid-phase enzyme-linked immunoassay in 14 children with Crohn's disease, in 9 with juvenile chronic arthritis, and in 7 controls . The immunostimulatory effect of Lactobacillus GG was specific for Crohn's disease, irrespective of its activity: the mean (95% confidence interval) number of specific antibody secreting cells in the IgA class to beta-lactoglobulin increased significantly from 0.2 (0.04-1.3) to 1.4 (0.3-6.0)/10(6) cells and to casein from 0.3 (0.1-1.4) to 1.0 (0.2-4.8)/10(6) cells . The results indicate that orally administered Lactobacillus GG has the potential to increase the gut IgA immune response and thereby to promote the gut immunological barrier . Consequently, Lactobacillus GG could provide an adjunct nutritional therapy for Crohn's disease. Caries Res, 1996, 30(3), 180 - 8 Properties of whole saliva and dental plaque in relation to 40-month consumption of chewing gums containing xylitol, sorbitol of sucrose; Makinen KK et al.; Samples of whole saliva and dental plaque were collected from initially 10-year old subjects who participated in a 40-month cohort study investigating the effect of chewing gum usage on caries rates . The subjects represented nine cohorts of which one did not receive gum, while in eight cohorts the subjects received gum containing either xylitol, sorbitol, their mixtures, or sucrose as bulk sweeteners, the maximum sweetener consumption in the form of gums being up to 10.7 g/day, used in 3-5 daily chewing episodes . Gum usage had no significant effect on the levels of salivary protein, IgA, alpha-amylase, peroxidase, lysozyme, SCN and buffer capacity . At the endpoint, the group that received 100% xylitol pellet-shaped gum five times/day, had significantly lower levels of sucrase (p <0.05) and free sialic acid (p < 0.001) in whole saliva than at baseline . This group showed significantly (p <0.05) smaller plaque index scores at two cross-sectional measurements, and exhibited the lowest log(10) counts of salivary lactobacilli at endpoint than most other groups . The salivary levels of peptidase(s) (oligopeptidase B-like enzymes) hydrolyzing N-alpha-benzoyl-DL-arginyl-p-nitroaniline were significantly (p<0.05) or almost significantly lower in groups which received 100% xylitol pellet gums . All groups exhibited obviously an aging-related increase of salivary mutans streptococcus scores, except the above xylitol group in which the mean scores did not change. Caries Res, 1996, 30(1), 52 - 64 Human root caries: microbiota of a limited number of root caries lesions; Schupbach P et al.; The microbiota of root caries lesions of different grades of severity were studied . Fourteen lesions were examined . The experimental design of the study allowed correlation of histopathologically distinguishable stages with specific and distinct microbial populations . Dentin samples were ground in a sterile mortar and cultured anaerobically on nonselective Columbia blood agar plates supplemented with 5% hemolyzed human blood and on media selective for Lactobacillus spp . and streptococci . The cultivable microbiota were quantitatively speciated using Rapid ID 32A, Rapid ID 32 Strep, API 20 Strep, APIZYM, and API50 CH tests and SDS-PAG electrophoresis . In initial as well as in advanced lesions gram-positive bacteria accounted for approximately 90% of the CFUt . The proportion of Actinomyces, and in particular A . naeslundii was significantly higher (p < 0.05) in initial lesions than in advanced lesions . In contrast, the percentage of Streptococcus and especially S . mutans was higher (p < 0.05) in advanced than in initial lesions . Surprisingly low (0.8% of the CFUt) was the percentage of lactobacilli in advanced lesions . Gram-negative bacteria formed a minor part of the microbiota in both initial and advanced lesions . Among the gram-negative isolates, Prevotella, Selenomonas, and Bacteroides spp . were most noticeable . In advanced lesions, only the outermost layer of 0.5 mm thickness was populated by a high number of bacteria; the following segments harbored a negligible number of bacteria only . It is concluded that root caries is a continuous destruction process which is restricted to a subsurface zone of limited depth . The necrotic dentin is successively worn away, leading to a saucer-shaped cavitation which is repopulated by plaque . The creation of cavitations favors an aciduric flora . This might explain the succession of bacterial populations observed during the destruction process. Caries Res, 1996, 30(1), 22 - 8 Evaluation of salivary tests and dental status in the prediction of caries increment in caries-susceptible teenagers; Vehkalahti M et al.; We evaluated caries increment in connection with salivary caries-related findings and dental status in teenagers by carrying out a retrospective follow-up, lasting on average 28 months . A total of 66 adolescents, mean age 15.2 years, were selected by their susceptibility to caries, as clinically defined at a routine checkup . Their baseline DMFT was 5.7, compared to 4.3 in the root population of 230 patients . Increment of caries on selected surfaces (delta DFSs) included new caries reaching the dentine and new fillings done due to such caries . Delta DFSs > 0 was taken as the validation criterion to define a caries case . Screening criteria for salivary tests were set as follows: flow rate of unstimulated saliva less than 0.2 ml/min, and of stimulated saliva less than 1.0 ml/min; buffering capacity: final pH below 4.5, mutans streptococci (SM) score of 2 or 3 (> or = 10(5) CFU/ml), and lactobacilli (LB) score of 5 or 6 (> or = 10(5) CFU/ml) . Mean delta DFSs per subject was 1.1, with 70% of these new DF findings being on occlusal surfaces . Delta DFSs was correlated with LB (0.31) for both genders, for boys only with buffering capacity (-0.34), and for girls only with flow rate of stimulated saliva (-0.28) and DMFT (0.35) . The highest sensitivities of salivary tests for caries were shown by LB (0.82) and SM (0.64), their specificities being 0.63 and 0.59, respectively . Positive predictive values of the five tests varied between 0.69 and 0.89 . Predictions based on DMFT showed a sensitivity of 0.87 for DMFT > 3, but only of 0.33 for DMFT > 7, the corresponding specificities being 0.44 and 0.81. Caries Res, 1996, 30(2), 112 - 8 An in vitro microbial model for studying secondary caries formation; Fontana M et al.; Secondary caries is a major reason for the replacement of restorations . Because it is hypothesized that the development of secondary caries is closely associated with pathogenic oral bacteria, an in vitro microbial model has been developed to produce secondary carious lesions . A mixture of overnight cultures of Streptococcus mutans and Lactobacillus casei in dextrose-free trypticase soy broth, supplemented with 5% sucrose (TSBS), at 37 degrees C was used in this model as the inoculum for the experimental groups . Uninoculated control groups were incubated with medium only . Groups of human tooth specimens restored using composite, together with their respective controls, were exposed for 7 or 12 days to circulating cycles of TSBS (30 min each, 3 times per day) and a mineral wash solution (for a total of 22.5 h per day), at 37 degrees C . The pH of the experimental groups dropped to 4.l-4.5 during the test periods . The pH of the control groups remained at 6.8-7.0 . The inoculated bacteria remained viable throughout the study . No contamination of experimental or control samples occurred . Laser scanning confocal microscopy demonstrated the development of incipient surface and wall lesions in all the specimens of experimental groups in as few as 7 days . Reproducibility of the model was confirmed in a second investigation . Therefore, it was concluded that this model can be used for studying the microbial etiology and prevention of secondary caries. Biosci Biotechnol Biochem, 1996 Jan, 60(1), 139 - 41 Purification and characterization of 6-phospho-beta-galactosidase from Lactobacillus gasseri JCM 1031; Suzuki M et al.; 6-Phospho-beta-galactosidase from Lactobacillus gasseri JCM 1031 was purified from lactobacilli to homogeneity, about 118-fold, with 0.5% recovery by several chromatographies . The molecular mass and isoelectric point of the purified enzyme were 58 kDa and pI 5.5, respectively . The Km and Vmax for o-nitrophenyl-beta-D-galactopyranoside-6-phosphate were 0.8 mM and 116.4 mumol/min/mg, respectively . Reducing agent, Fe2+ ion, and EDTA activated but PCMB, Zn2+, and Hg2+ ions strongly inhibited the enzymatic activity. Arzneimittelforschung, 1996 Jan, 46(1), 68 - 73 Therapy of bacterial vaginosis using exogenously-applied Lactobacilli acidophili and a low dose of estriol: a placebo-controlled multicentric clinical trial; Parent D et al.; The efficacy of vaginal tablets (Gynoflor) containing 50 mg of a lyophilisate of viable, H2O2-producing Lactobacillus acidophilus (at least 10(7) colony forming units/tablet) and 0.03 mg estriol (CAS 50-27-1) for the treatment of bacterial vaginosis (BV) was tested in a multicentric, randomised, placebo-controlled clinical trial with parallel-group design . 32 non-menopausal women with positive diagnoses for BV, including intermediate cases, participated in the trial . Patients were diagnosed using the classical clinical parameters of BV according to Amsel and using microscopic analysis of the Gram-stained vaginal smear . A positive clinical diagnosis of BV required at least 2 of the following 4 clinical criteria to be positive; greyish-white, homogeneous leukorrhea; vaginal pH > 4.5; KOH test for volatile amines; presence of clue cells . Microscopic diagnosis of BV, on the other hand, was obtained if examination of the Gram-stained vaginal smear showed less than 6 lactobacilli per field of view (1000 x magnification) . This corresponds to another definition of BV as "lactobacilli deficiency syndrome" . The efficacy of the 6-day therapy with 1-2 vaginal tablets daily was evaluated using both clinical and microscopic analysis . Using Amsel's classical clinical parameters of BV, the cure rate (defined as < or = 1 of the 4 clinical criteria positive) two weeks after the start of therapy was 77% in the verum group and 25% in the placebo group . Four weeks after the start of therapy, the cure rate was 88% in the verum group and 22% in the placebo group . At both control examinations, the cure rate for the test group was significantly higher than that for the placebo group (p < 0.05, Fisher's exact test, 2-sided, significance level 0.05) . In addition, the trial showed that after 6 days of treatment with the test preparation, the lactobacilli were capable of recolonising the vagina . A significant increase in the number of lactobacilli was observed in the Gram-stained vaginal smear for the patient group treated with the test preparation compared to the placebo patient group (p < 0.05, Fisher's exact test, 2-sided, significance level 0.05), two and four weeks after the start of the 6-day treatment. Biol Pharm Bull, 1996 Jan, 19(1), 88 - 93 Effect of lactobacilli and antibiotics on E . coli urinary infections in mice; Silva de Ruiz C et al.; Urinary antibiotic treatments usually affect the normal urethral flora . This work was developed in order to evaluate whether Lactobacillus fermentum CRL 1058 could reduce urinary tract infections (UTI) produced by uropathogenic Escherichia coli in mice treated with antimicrobial agents . Animals were inoculated intra-urethrically with agarose beads containing lactobacilli, and were challenged with E . coli . Ampicillin (13 mg/kg/dose) was administered orally . The number of microorganisms present at different days was evaluated in the urogenital tract . Serum inflammatory and systemic immune response were also registered . The use of 5 doses of ampicillin after 3 doses of lactobacilli in agarose beads significantly affected the viability of lactic acid bacteria, while the amount of E . coli was not altered . Lactate dehidrogenase (LDH) activity and anti-E . coli antibody levels showed no statistically significant difference between the challenged and non-challenged mice . Lactobacilli reinoculation and 3 doses of ampicillin proved to be a moderately effective treatment since a smaller amount of E . coli was recovered from the organs of treated mice than from the controls . The reinforcement of lactobacilli, administered on the 9th day, produced a faster elimination of the pathogen . The ampicillin dose used allowed lactobacilli permanence in the urinary tract, and caused the elimination of the pathogen . Serum LDH values seemed to show an inflammatory immune response . No successful preventive results could be achieved . We can conclude that lactobacilli and adequately low doses of ampicillin have a positive effect on the treatment of E . coli in this UTI model. Biochimie, 1996, 78(1), 3 - 13 Molecular cloning and characterization of the pyrB gene of Lactobacillus leichmannii encoding aspartate transcarbamylase; Becker J et al.; The Lactobacillus leichmannii pyrB gene, encoding pyrimidine biosynthetic enzyme aspartate transcarbamylase (ATCase), was cloned from a partial genomic library lying on a 1468 bp Sa/I/BstXI fragment . The predicted polypeptide sequence extending over 351 amino acid residues (M(r) 39 855 Da) was compared to those of various other organisms revealing clear identities towards them and important conservative stretches, implying that these proteins are closely related . Transcriptional initiation was mapped by primer extension and occurred 54 bp upstream of the pyrB open reading frame (ORF) . Northern blot analysis indicates that the pyrB gene is transcribed as a single mRNA and not together with the following overlapping pyrC gene as a bicistronic mRNA . At high copy number the pyrB gene of L leichmannii seems to be lethal for its E coli host; inserted in a low copy vector it complements the uracil auxotrophy of an E coli pyrB mutant which shows distinct ATCase activity in the cell extract . With an excess of uracil in the growth medium the gene is apparently repressed and no ATCase activity can be measured. Nutr Cancer, 1996, 25(2), 197 - 204 The effect of Lactobacillus GG on the initiation and promotion of DMH-induced intestinal tumors in the rat; Goldin BR et al.; Male Fischer 344 rats were fed a 20% or a 5% corn oil diet and were injected subcutaneously with dimethylhydrazine (DMH) weekly for 16 weeks . In addition, an approximately equal number of animals challenged with DMH were fed daily, until the end of the study, 2 x 10(10) Lactobacillus casei subsp . rhamnosus strain GG starting three weeks before DMH administration or after the ninth weekly injection . The feeding of the Lactobacillus GG before and during carcinogen treatment resulted in a significant decrease in the incidence of colon tumors and the number of small intestinal and colon tumors per tumor-bearing animal for rats fed a 20% corn oil diet . This decrease in tumor incidence or number of tumors was not seen when animals were fed the Lactobacillus after the ninth week of carcinogen treatment . Animals fed a 5% corn oil diet had a lower tumor incidence and number of tumors resulting from the decrease in dietary fat; in addition the feeding of Lactobacillus GG before the carcinogen challenge resulted in a lower incidence of colon tumors . These studies show that a specific strain of L . casei subsp . rhamnosus designated GG can interfere with the initiation or early promotional stages of DMH-induced intestinal tumorigenesis, and this effect is most pronounced for animals fed a high-fat diet. J Appl Bacteriol, 1996 Jan, 80(1), 91 - 8 Production of brevicin 286 by Lactobacillus brevis VB286 and partial characterization; Coventry MJ et al.; Brevicin 286 was produced by Lactobacillus brevis VB286 isolated from vacuum-packaged meat and was partially purified by ammonium sulphate precipitation, gel filtration and dialysis . The bacteriocin was susceptible to proteolytic enzymes, stable to heating at 100 degrees C particularly under acidic against Listeria sp . Production of brevicin 286 was optimal during exponential growth at 20 degrees C . Higher rates of cell growth occurred between 30 and 37 degrees C but with little or no expression of brevicin 286 . A food-grade formulation consisting of 4% yeast extract and 1% glucose was found to be adequate for optimal brevicin 286 production and the bacteriocin-containing culture supernate was successfully spray dried with full recovery of antibacterial activity in the resultant powder. Miner Electrolyte Metab, 1996, 22(1-3), 92 - 6 Biomodulation of the toxic and nutritional effects of small bowel bacterial overgrowth in end-stage kidney disease using freeze-dried Lactobacillus acidophilus; Simenhoff ML et al.; Small bowel bacterial overgrowth (SBBO), well known to occur in end-stage kidney failure, is responsible for producing uremic toxins and contributing to the patient's decreased nutritional well-being . In this study, 8 hemodialysis patients were treated with a course of oral Lactobacillus acidophilus (LBA) in an attempt to alter this SBBO . LBA treatment was effective in lowering 2 compounds generated in vivo . Serum dimethylamine (DMA) levels dropped from 224 +/- 47 to 154 +/- 47 micrograms/dl at the end of LBA treatment (p < 0.001) . Nitrosodimethylamine, a carcinogen, levels also decreased significantly from 178 +/- 67 (untreated) to 83 +/- 49 ng/kg (after LBA treatment) . Patients nutritional status, assessed as serum albumin, body weight, caloric intake, midarm muscle area (MAMA) and appetite improved modestly, but not significantly . LBA changed small bowel pathobiology by modifying metabolic actions of SBBO, reducing in vivo generation of toxins and carcinogens and promoting nutrition with no adverse side effects. J Clin Pediatr Dent, 1996 Spring, 20(3), 241 - 5 Salivary caries risk factors in long-term event-free survivors of pediatric malignant diseases; Dens FL et al.; In this study we demonstrated that caries prevalence and Plaque Index in long-term event-free pediatric oncology patients are related to Streptococcus mutans, Lactobacillus counts and buffer capacity obtained by chairside saliva tests . The scores showed a significant correlation between the microbiological findings and caries experience in both groups . The results were compared with a control group . A similarity in the results was found between the study and control groups . In a subgroup consisting of children who were diagnosed with cancer maximum two years before oral examinations, no significant differences with a control group was noticed . In this study we did not find any evidence of long-term effects on the studied salivary caries risk factors in children who are long-term event-free after cytotoxic treatment . Chairside tests seem to be useful in this patient group: they provide us information which can contribute to the determination of the individual caries risk, and help to motivate the patient and health care workers to maintain optimal oral hygiene. Clin Immunol Immunopathol, 1996 Jan, 78(1), 30 - 40 The induction of cardioangitis by Lactobacillus casei cell wall in mice . I . The cytokine production from murine macrophages by Lactobacillus casei cell wall extract; Okitsu-Negishi S et al.; A single intraperitoneal injection of the water-soluble cell wall extract from Lactobacillus casei (LCWE) in mice can induce acute inflammatory heart involvement such as cardiac arteritis, similar to the heart lesions in Kawasaki disease . To clarify whether inflammatory cytokines participate in pathogenic mechanisms of LCWE-induced cardioangitis in mice, we studied in vitro cytokine production (IL-1, TNF alpha, and IL-6) from peritoneal macrophages (M phi) stimulated with LCWE in comparison with that of lipopolysaccharide (LPS) . LCWE significantly activated M phi of BALB/c in production of IL-1 and TNF alpha compared with LPS . However, the magnitude of IL-6 synthesis by LCWE was approximately similar to that of LPS . These results demonstrate that the pathogenesis of LCWE- induced cardiac lesions may be associated with increased production of inflammatory cytokines. Int J Syst Bacteriol, 1996 Jan, 46(1), 337 - 40 Reclassification of Lactobacillus casei subsp . casei ATCC 393 and Lactobacillus rhamnosus ATCC 15820 as Lactobacillus zeae nom . rev., designation of ATCC 334 as the neotype of L . casei subsp . casei, and rejection of the name Lactobacillus paracasei; Dicks LM et al.; The type strain of Lactobacillus casei subsp . casei (ATCC 393) exhibits low levels of DNA homology with other strains of L . casei subsp . casei (8 to 46%) and strains of Lactobacillus paracasei (30 to 50%), but exhibits a level of DNA similarity of 80% with Lactobacillus rhamnosus ATCC 15820, the original type strain of "Lactobacterium zeae" Kuznetsov 1959 . Strains ATCC 393T (T = type strain) and ATCC 15820T are members of one protein profile cluster that is separate from the other Lactobacillus spp . The randomly amplified polymorphic DNA PCR profile of strain ATCC 393T is also different from the profiles obtained for the other species . L . casei ATCC 334T is genetically closely related to L . casei subsp . casei strains (71 to 97%) and L . paracasei strains (71 to 91%), is a member of the same protein profile cluster as these organisms, and shares several DNA amplicons with L . paracasei strains . On the basis of these results, we propose that L . casei subsp . casei ATCC 393T and L . rhamnosus ATCC 15820 should be reclassified as members of Lactobacillus zeae nom . rev . (type strain, ATCC 15820), that strain ATCC 334 should be designated the neotype strain of L . casei subsp . casei, and that the name L . paracasei should be rejected. J Bacteriol, 1996 Jan, 178(1), 314 - 6 Identification of an anaerobically induced phosphoenolpyruvate-dependent fructose-specific phosphotransferase system and evidence for the Embden-Meyerhof glycolytic pathway in the heterofermentative bacterium Lactobacillus brevis; Saier MH Jr et al.; Heterofermentative gram-positive bacteria are believed to metabolize sugars exclusively via the pentose phosphoketolase pathway following uptake via sugar:cation symport . Here we show that anaerobic growth of one such bacterium, Lactobacillus brevis, in the presence of fructose induces the synthesis of a phosphotransferase system and glycolytic enzymes that allow fructose to be metabolized via the Embden-Meyerhof pathway. Mol Gen Genet, 1995 Dec 20, 249(6), 682 - 90 Cloning and characterization of brnQ, a gene encoding a low-affinity, branched-chain amino acid carrier in Lactobacillus delbrückii subsp . lactis DSM7290; Stucky K et al.; A gene (brnQ), encoding a carrier for branched-chain amino acids in Lactobacillus delbruckii subsp . lactis DSM7290 was cloned in the low-copy-number vector pLG339 by complementation of a transport-deficient Escherichia coli strain . The plasmid carrying the cloned gene restored growth of an E . coli strain mutated in 4 different branched-chain amino acid transport genes at low concentrations of isoleucine, and increased its sensitivity to valine . Transport assays showed that leucine, isoleucine and valine are transported by this carrier and that transport is driven by the proton motive force . Nucleotide sequence analysis revealed an open reading frame of 1338 bp encoding a hydrophobic protein of 446 amino acids with a calculated molecular mass of 47864 Daltons . The start site of brnQ transcription was determined by primer extension analysis using mRNA from Lactobacillus delbruckii subsp . lactis DSM7290 . The hydropathy profile suggests the existence of at least 12 hydrophobic domains that probably form membrane-associated alpha-helices . Comparisons of the nucleotide sequence of brnQ from Lactobacillus delbruckii subsp . lactis DSM7290, the amino acid sequence of its product and the topology of the hydrophobic domains with those of the respective carrier genes and proteins of Salmonella typhimurium and Pseudomonas aeruginosa revealed extensive homology. Clin Infect Dis, 1995 Dec, 21(6), 1460 - 2 Lactobacillemia in three patients with AIDS; Horwitch CA et al.; Lactobacillemia, an uncommon cause of bacteremia, has been reported to occur in one renal transplantation patient who was also infected with human immunodeficiency virus (HIV) . We present the cases of three patients with AIDS in whom lactobacillemia developed . All three patients had late-stage AIDS with CD4 cell counts of < 55/mm3, all had indwelling central venous catheters, and all were recently or concomitantly blood culture-positive for coagulase-negative staphylococci . In addition, two of the three patients had recently received vancomycin therapy . These three cases provide the first association of lactobacillus bacteremia and AIDS. Am J Dent, 1995 Dec, 8(6), 323 - 8 The microbiology and histopathology of human root caries; Zambon JJ et al.; Based on numerous microbiological studies performed over the past several decades, it is clear that mutans streptococci can cause human root caries . S . mutans fulfills the criteria for implicating bacteria in the etiology of a mixed infection . For example, S . mutans is found in high numbers in lesion sites, higher than on sound root surfaces in the same subject . Subjects make elevated antibody levels to S . mutans antigens . The organism produces a number of virulence factors including metabolic acid from dietary sucrose and extracellular polysaccharides which facilitate bacterial colonization of tooth surfaces . Eliminating or reducing the number of S . mutans reduces the number of root caries lesions and can even result in "healing" of incipient lesions . There is also data demonstrating the cariogenic potential of S . mutans in animal models . Clearly, S . mutans fulfills the aforementioned requirements . Further, there is also evidence to implicate Lactobacillus as being important in the pathogenesis of root caries by virtue of its association with S . mutans in these lesions . There is less recent evidence regarding the importance of Actinomyces in this disease . While this microorganism is present in root caries and while animal studies clearly point to their cariogenic potential, more recent studies with few exceptions fail to find much association between Actinomyces and root caries . There is an important caveat, however . The Actinomyces may have subspecies groups which are more highly virulent and more closely involved in the etiology of root caries than other groups . For example, A . viscosus serovar 2 is associated with root caries . This and other subspecies groups may produce certain virulence factors not found within Actinomyces species as a whole . For this group of microorganisms and for other potential pathogens, techniques in molecular biology such as 16S ribosomal RNA sequencing offers the hope of more precisely defining species and unraveling what may be largely problems in bacterial taxonomy . Ribosomal RNA sequencing may reveal taxonomic relationships not apparent with classical phenotypic or serologic analyses . Other molecular methods, such as DNA or RNA probes to specific virulence factors may also reveal relationships between clinical lesions and microorganisms possessing these virulence factors . Finally, there are clearly a number of additional species which may have importance in root surface caries as shown in some studies . These techniques can be used to identify the distribution of novel, even uncultivable bacteria in root caries lesions and in this way establish their role in this important disease. Oral Microbiol Immunol, 1995 Dec, 10(6), 349 - 54 Effect of acetate on sorbitol fermentation by oral lactobacilli; Takahashi N et al.; The rate of acid production and end-products from sorbitol were measured under anaerobic conditions in washed-cell suspensions of oral strains of Lactobacillus casei subsp . casei and Lactobacillus casei subsp . rhamnosus . The enzymatic activities were assayed in cell extracts of these strains . The cells fermented sorbitol to lactate, formate, ethanol and acetate under anaerobic conditions . Exposure of the cells to air (oxygen) led to inactivation of pyruvate formate-lyase and inhibition of anaerobic sorbitol fermentation . In the presence of acetate, air-exposed cells fermented sorbitol with a concomitant consumption of acetate and production of ethanol and lactate . Acetate also enhanced acid production from sorbitol in cells kept under anaerobic conditions and resulted in formation of lactate and ethanol . Cell extracts of all the strains had NADH-coupled acetate-reducing activity, which consisted of sequential reactions of acetate kinase, phosphotransacetylase, acylating aldehyde dehydrogenase and alcohol dehydrogenase . These findings indicate that oral lactobacilli can utilize acetate as an electron acceptor for maintaining their intracellular redox balance during anaerobic sorbitol fermentation in the absence of pyruvate formate-lyase activity. Microbiology, 1995 Dec, 141 ( Pt 12), 3067 - 75 An X-prolyl dipeptidyl aminopeptidase (pepX) gene from Lactobacillus helveticus; Vesanto E et al.; The X-prolyl dipeptidyl aminopeptidase gene (pepX) of an industrially used Lactobacillus helveticus strain has been detected by nucleic acid hybridization, cloned, characterized and sequenced . One ORF of 2379 bp with coding capacity for a 90.6 kDa protein (PepX) was found . The ORF was preceded by a typical prokaryotic promoter region . An inverted repeat structure with delta G of -84.1 kJ mol-1 was found downstream of the coding region . The deduced amino acid sequence of the 90.6 kDa protein showed 49.3, 49.4 and 77.7% homology with the PepX proteins from Lactococcus lactis subsp . lactis, Lc . lactis subsp . cremoris and Lactobacillus delbrueckii subsp . lactis, respectively . Northern blotting revealed a 2.6 kb transcript and one transcription start site was identified via primer extension analysis using an A.L.F . sequencer . In a bioreactor study, the expression of pepX in Lb . helveticus was studied as a function of growth . Transcription of pepX was typical of exponential growth phase expression . The pepX gene has been cloned into pKK223-3 and expressed at a high level in Escherichia coli JM105 . PepX was purified to homogeneity by ion-exchange and hydrophobic interaction chromatography . Optimum PepX activity was observed at pH 6.5 and 45 degrees C . According to gel filtration analysis, PepX is a dimer of 165 kDa . The enzyme was inactivated by heavy metal ions such as Cu2+, Cd2+ and Zn2+ . EDTA and 1,10-phenanthroline did not decrease PepX activity significantly . It was completely inhibited by p-hydroxymercuribenzoate and reactivated by adding DTT, and strongly inhibited by PMSF . PepX is thus a metal-independent serine peptidase having functional sulfhydryl groups at or near the active site. Microbiology, 1995 Dec, 141 ( Pt 12), 3059 - 66 Two genes encoding the beta-galactosidase of Lactobacillus sake; Obst M et al.; The beta-galactosidase of Lactobacillus sake DSM 20017 is encoded by two genes located on its chromosome . These genes designated lacL and lacM were cloned in Escherichia coli NM 554 on an 8.65 kbp HindIII fragment inserted in vector pRB473 . Deletion analysis of the originally cloned fragment revealed that both genes are required for the formation of a functional beta-galactosidase . lacL and lacM are transcribed as a single transcript of approximately 2.9 kbp starting 34 bp upstream of the translational start codon . The proteins derived from lacL and lacM share only 18-59% homology with other beta-galactosidases . The genes encoding the beta-galactosidase are scattered with multiple direct and inverted repeats of 9-12 bp . However, comparison with the plasmid-encoded Leuconostoc lactis beta-galactosidase revealed equal distribution of conserved amino acid residues and suggests that the genes have a common origin . Specific deletions or insertions resulting from the presence of the repeats were not observed . The L . sake beta-galactosidase was phenotypically expressed in E . coli NM 554 and Lactobacillus curvatus LTH 1432 . Its two genes can be used to replace antibiotic reporter genes to develop food-grade vectors and alpha-complementation systems for self-cloning in meat lactobacilli. Lett Appl Microbiol, 1995 Dec, 21(6), 384 - 6 Cloning and nucleotide sequence of the gene for acidocin 8912, a bacteriocin from Lactobacillus acidophilus TK8912; Kanatani K et al.; Acidocin 8912 is a bacteriocin produced by Lactobacillus acidophilus TK8912 . The acidocin 8912 structural gene, acdT, was cloned and determined . It was located on the 14-kb plasmid pL103 and encoded a 46 amino acid precursor including a 20 amino acid N-terminal extension . The precursor sequence of the acdT gene shows a conservation of the general structural characteristics of the bacteriocin precursors from some lactic acid bacteria. Lett Appl Microbiol, 1995 Dec, 21(6), 351 - 3 Aggregation-promoting factor in pig intestinal Lactobacillus strains; Kmet V et al.; Autoaggregation was frequently encountered among intestinal lactobacilli isolated from weaned pigs . The aggregation mechanism was shown to be mediated by the production of a proteinaceous aggregation-promoting factor in two strains of Lactobacillus reuteri . A 32 kDa aggregation-promoting protein was detected in these strains by cross-reaction with rabbit polyclonal antibodies for Aggregation-Promoting Factor produced by the human isolate Lact . plantarum 4B2 . Coaggregation reactions of Lact . reuteri strains with pathogenic and non-pathogenic Escherichia coli were detected. Appl Environ Microbiol, 1995 Dec, 61(12), 4459 - 63 Purification and partial amino acid sequence of plantaricin S, a bacteriocin produced by Lactobacillus plantarum LPCO10, the activity of which depends on the complementary action of two peptides; Jimenez-Diaz R et al.; Plantaricin S, one of the two bacteriocins produced by Lactobacillus plantarum LPCO10, which was isolated from a green-olive fermentation (R . Jimenez-Diaz, R.M . Rios-Sanchez, M . Desmazeaud, J.L.Ruiz-Barba, and J.-C . Piard, Appl . Environ . Microbiol . 59:1416-1424, 1993), has been purified to homogeneity by ammonium sulfate precipitation, by binding to SP-Sepharose fast-flow, phenyl-Sepharose CL-4B, and C2/C18 reverse-phase chromatographies . The purification resulted in a final yield of 91.6% and a 352,617-fold increase in the specific activity . The bacteriocin activity was associated with two distinct peptides, termed alpha and beta, which were separated by C2/C18 reverse-phase chromatography . Although beta alone appeared to retain a trace of inhibitory activity, the complementary action of both the alpha and beta peptides was required for full bacteriocin activity, as judged by both the agar well diffusion and the microtiter plate assays . From the N-terminal end, 26 and 24 amino acids residues of alpha and beta, respectively, were sequenced . Further attempts at sequencing revealed no additional amino acids residues, suggesting that either modifications in the next amino acid residue blocked the sequencing region or that the C-terminal end had been reached . The amino acid sequences of alpha and beta show no apparent homology to each or to other bacteriocins purified from lactic acid bacteria. J Bacteriol, 1995 Dec, 177(24), 7222 - 30 Identification, cloning, and nucleotide sequence of a silent S-layer protein gene of Lactobacillus acidophilus ATCC 4356 which has extensive similarity with the S-layer protein gene of this species; Boot HJ et al.; The bacterial S-layer forms a regular structure, composed of a monolayer of one (glyco)protein, on the surfaces of many prokaryotic species . S-layers are reported to fulfil different functions, such as attachment structures for extracellular enzymes and major virulence determinants for pathogenic species . Lactobacillus acidophilus ATCC 4356, which originates from the human pharynx, possesses such an S-layer . No function has yet been assigned to the S-layer of this species . Besides the structural gene (slpA) for the S-layer protein (S-protein) which constitutes this S-layer, we have identified a silent gene (slpB), which is almost identical to slpA in two regions . From the deduced amino acid sequence, it appears that the mature SB-protein (44,884 Da) is 53% similar to the SA-protein (43,636 Da) in the N-terminal and middle parts of the proteins . The C-terminal parts of the two proteins are identical except for one amino acid residue . The physical properties of the deduced S-proteins are virtually the same . Northern (RNA) blot analysis shows that only the slpA gene is expressed in wild-type cells, in line with the results from sequencing and primer extension analyses, which reveal that only the slpA gene harbors a promoter, which is located immediately upstream of the region where the two genes are identical . The occurrence of in vivo chromosomal recombination between the two S-protein-encoding genes will be described elsewhere. Obstet Gynecol, 1995 Dec, 86(6), 925 - 30 Effect of Candida albicans infection and clotrimazole treatment on vaginal microflora in vitro; Ross RA et al.; OBJECTIVE: To determine the effect of Candida albicans infection and clotrimazole treatment on vaginal microflora . METHODS: Studies were conducted using a model simulating the healthy vaginal ecosystem . The model consisted of a mixed culture of Lactobacillus acidophilus, Staphylococcus epidermidis, Prevotella bivia, and group D Streptococcus sp grown in continuous culture in a chemically defined medium . The status of the model was assessed using a mathematical equation that determines the probability a microflora is normal or abnormal . RESULTS: Challenge of the model with C albicans was followed within 24 hours by the development of microbial populations representing an abnormal microflora . Treatment of the system with clotrimazole (100 micrograms/mL) resulted in a decrease in C albicans counts to 0 within 48 hours . However, treatment also altered other components of the vaginal microflora, which did not return to normal . Addition of clotrimazole (100 micrograms/mL) to the system in the absence of C albicans also resulted in an abnormal model by 24 hours . CONCLUSIONS: Candida albicans infection of the vaginal ecosystem, as represented by this in vitro model, has a deleterious effect on members of the normal microflora . Clotrimazole, although effective against C albicans infection, also has a deleterious effect on components of the normal vaginal microflora . One of the implications for women using clotrimazole for microbiologically undocumented vaginal yeast infections is an increased risk of infection or disease through the disruption of the protective microflora barrier. J Fam Pract, 1995 Dec, 41(6), 575 - 81 Office laboratory diagnosis of vaginitis . Clinician-performed tests compared with a rapid nucleic acid hybridization test; Ferris DG et al.; BACKGROUND . The traditional diagnosis of vaginitis incorporates patient symptoms, clinical findings observed during vaginal examination, and laboratory analysis of vaginal fluid . The purpose of this study was to evaluate routine clinician-performed office laboratory diagnostic techniques for women with abnormal vaginal symptoms, and to compare these results with those obtained by a DNA hybridization test for Trichomonas vaginalis, Gardnerella vaginalis, and Candida species . METHODS . The study included 501 symptomatic women who were between the ages of 14 and 67 years . Three vaginal specimens were obtained for saline wet mount, potassium hydroxide (KOH) prep, amine "sniff", pH, and nucleic acid hybridization (T vaginalis, G vaginalis, and Candida sp) tests . Clinicians and medical technicians independently evaluated the wet mount, KOH prep, amine, and pH tests . A medical technician processed the DNA tests according to manufacturer's protocol . RESULTS . Of 499 subjects for whom complete data were available, vulvovaginal candidiasis was diagnosed in 20.0%, vaginal trichomoniasis in 7.4%, and bacterial vaginosis in 52.1% . Fourteen percent of subjects had multiple vaginal infections . The sensitivity and specificity of clinician microscopically diagnosed vulvovaginal candidiasis, vaginal trichomoniasis, and bacterial vaginosis were 39.6% and 90.4%, 75.0% and 96.6%, and 76.5% and 70.8%, respectively . The sensitivity and specificity of the DNA probe diagnosis of the same types of vaginitis were 75.0% and 95.7%, 86.5% and 98.5%, and 95.4% and 60.7%, respectively . When only women with multiple vaginal infections were considered, the percentages of correct clinician diagnoses for vulvovaginal candidiasis, vaginal trichomoniasis, and bacterial vaginosis were 49.3%, 83.6%, and 59.7%, respectively . For the DNA probe test, the percentages of correct diagnoses were 72.9%, 92.9%, and 90.0%, respectively . CONCLUSIONS . Primary care clinicians demonstrated a high specificity but low sensitivity when identifying vaginal trichomoniasis and vulvovaginal candidiasis by microscopic techniques . Correct microscopic diagnosis of bacterial vaginosis was even more difficult for clinicians, as was the diagnosis of multiple vaginal infections . Clinicians were not as accurate as the DNA probe test in diagnosing vaginal infections . Clinicians need more education in the laboratory diagnosis of vaginitis . Clinicians should carefully scrutinize each microscopic slide, systematically examine the slide for each type of vaginitis, and consider specimen pH and the presence of leukocytes, Lactobacillus organisms, or amine odor as additional clues to infection. Schweiz Rundsch Med Prax, 1995 Nov 28, 84(48), 1405 - 15 {Causes and consequences of an unbalanced vaginal ecosystem}; Kunz J; The vaginal microflora of a healthy asymptomatic woman is part of a dynamic ecosystem which is easily disturbed by known and unknown factors . The normal vaginal microflora consists of a broad spectrum of aerobic and anaerobic germs . The anaerobic microaerophilic Doederlin's bacillus (lactobacillus) plays a major role in the microflora, but is only one of the many factors controlling and tuning a well-balanced ecosystem . Although our understanding is still insufficient, basic knowledge of the ecosystem and new results lead to a successful therapeutic approach. Clin Exp Rheumatol, 1995 Nov-Dec, 13(6), 725 - 31 Subjective and clinical oral symptoms in patients with primary Sjögren's syndrome; Lundstrom IM et al.; OBJECTIVE: To study subjective and clinical oral symptoms and their possible correlations in patients with primary Sjogren's syndrome (1 degree SS) . METHODS: In 40 cases fulfilling the Copenhagen as well as the San Diego criteria for 1 degree SS, different subjective symptoms were registered during an interview and by using a questionnaire and visual analogue scales (VAS) . A clinical examination was performed to record the salivary parameters, dental status, candidosis, other mucosal lesions, and oral dysfunction . RESULTS: Subjectively, dryness was reported by 98%, soreness by 63%, angular lesions by 70%, and mucosal ulcerations by 40% of the patients . Frequent carious lesions were a major subjective complaint . Clinically, the dental status did not differ from that of the Swedish general population except for a somewhat increased number of filled and decayed surfaces, here 3.5 per tooth on the average . Candidosis was present in a total of 30 patients (75%), and angular cheilitis in 14 (35%) . Intraoral cultivation of Candida did not correlate with the clinical findings . Very high counts of lactobacilli and mutans streptococci were found in 77% and 47% of the patients, respectively . Decreased unstimulated saliva was significantly correlated to the subjective degree of dryness, while decreased stimulated saliva could be correlated to increased focus scores in labial salivary gland biopsies and to the presence of mucosal candidosis . Statistically significant correlations were also noted between focus scores and the grades of subjective and clinical dryness . Lichenoid lesions were seen in 18% and oral dysfunction in 55% of the 1 degree SS patients . CONCLUSION: The impaired salivary function in 1 degree SS can be related to several subjective complaints and clinical disorders . Increased attention to and treatment of the symptoms noted is a necessity for the early diagnosis and relief of oral distress. Mol Microbiol, 1995 Nov, 18(4), 631 - 9 A bacteriocin-like peptide induces bacteriocin synthesis in Lactobacillus plantarum C11; Diep DB et al.; In this study, we show that bacteriocin production in Lactobacillus plantarum C11 is an inducible process triggered by a secreted protein factor produced by the bacteriocin producer itself . The induction factor was identified to be plantaricin A, a bacteriocin-like peptide whose gene (plnA) is located in the same operon as a two-component regulatory system (plnBCD) . When L . plantarum C11 cultures were depleted for plantaricin A, either by growing individual colonies on agar plates or by starting a new culture with a highly diluted inoculum, no bacteriocin was produced during the following growth . When chemically synthesized plantaricin A or purified bacterially produced plantaricin A was added to non-producing cultures, bacteriocin production was induced . Only 1 ng ml-1 plantaricin A is sufficient to induce the bacteriocin production in non-producing L . plantarum C11, and bacteriocin activity appears in the growth medium approximately 150 min after induction . Northern analyses, using a plnA-specific probe, demonstrated that plantaricin A is able to induce its own synthesis by transcription of the plnABCD operon, and this is observed approximately 15 min after adding plantaricin A . Furthermore, heterologous expression of the plnABCD operon in a Lactobacillus sake strain showed that the conditioned growth medium contained the active induction factor . Neither synthetic nor expressed plantaricin A from the heterologous system possesses any bacteriocin activity, suggesting that plantaricin A is primarily an induction factor and not a bacteriocin as claimed earlier. Int J Food Microbiol, 1995 Nov, 28(1), 89 - 100 Taxonomy of lactic acid bacteria associated with vacuum-packaged processed meat spoilage by multivariate analysis of cellular fatty acids; Dykes GA et al.; The taxonomy of lactic acid bacteria from vacuum-packaged processed meats is problematic, and atypical members of the leuconostocs and the Lactobacillus sake / curvatus group are often encountered . In order to resolve this problem the cellular fatty acid (CFA) content of 61 isolates from vacuum-packaged vienna sausages and 18 reference strains was determined by gas chromatography . The relationship between strains was derived by principal component analysis of data . The CFA profiles were highly reproducible . Although no relationships could be derived using only one or two differentiating CFAs, plots of the first two principal components based on only the six most variable CFAs allowed grouping of strains . The two genera (Leuconostoc and Lactobacillus) could not be clearly separated when analysed together, but differentiation of species within each of the genera was achieved when they were analysed independently . Examination of plots for the reference strains confirmed previously established relationships between these strains . From the plot of the Lactobacillus sake / Lactobacillus curvatus component of the study it was found that most atypical Lactobacillus sake / curvatus strains were closely related to the typical Lactobacillus sake isolates and reference strain, while the Lactobacillus curvatus strains formed an independent grouping . A small cluster of atypical strains, however, indicated that this relationship may not be true for all these strains . Among the leuconostocs only isolates of Leuconostoc mesenteroides could be clearly differentiated. J Dairy Sci, 1995 Nov, 78(11), 2326 - 35 Survival during frozen and subsequent refrigerated storage of Lactobacillus acidophilus cells as influenced by the growth phase; Brashears MM et al.; Cells of Lactobacillus acidophilus propagated in peptonized milk nutrient broth maintained at pH 5 were harvested during the late logarithmic (log) phase and at 6 h into the stationary phase of growth . Concentrated cultures were prepared from each age of cells, frozen, and stored at -196 degrees C . The concentrated cultures were assayed for numbers of total and bile-tolerant lactobacilli, beta-galactosidase activity, and ability to assimilate cholesterol before and after storage at -196 degrees C . Nonfermented acidophilus milk, prepared following 28 d of storage at -196 degrees C from each concentrated culture, was tested before and after 0, 7, 14, 21, and 28 d of storage at 7 degrees C . No decrease in numbers of total or bile-tolerant lactobacilli, beta-galactosidase activity, or amount of cholesterol assimilated was observed for any of three strains studied during storage at -196 degrees C . There were no significant differences between the two harvest times during storage at this temperature for any of the three strains . However, when the cells were suspended in milk and stored at 7 degrees C, the numbers of total and bile-tolerant lactobacilli declined over time as did the beta-galactosidase activity and the ability to assimilate cholesterol . The cells from L . acidophilus 223, harvested 6 h into the stationary phase, exhibited significantly less decrease in total numbers during extended storage at 7 degrees C than did the cells harvested in the late logarithmic phase . There was little or no difference in the decline in numbers of total lactobacilli between the two harvest times for strains 606 and 107 . All strains decreased significantly in beta-galactosidase activity and the ability to assimilate cholesterol during storage in milk at 7 degrees C with no significant differences between the two harvest times. J Endod, 1995 Nov, 21(11), 546 - 51 Microbial induction of dentinal caries in human teeth in vitro; Nagaoka S et al.; The ability of Lactobacillus casei, Streptococcus sobrinus, Actinomyces viscosus, and Streptococcus salivarius to induce dental caries was determined in vitro . A class I cavity (depth: 2mm) was prepared in extracted human caries-free premolars to make dentin blocks . The blocks were inoculated with these four bacterial strains in a monoinfective fashion and were incubated under anaerobic conditions . In addition to the monoinfection groups, mixed-infection groups of L . Casei with S . sobrinus or A . viscosus were also prepared . Half of the culture medium was renewed every 3 days, and the pH of the medium was measured . After 4 or 12 wk, these dentin blocks were prepared by Brown-Brenn staining and by contact microradiography for light microscopic observation and for immunohistochemical staining . The final pH of the S . salivarius group was the highest among the experimental groups, at approximately 5.1; that of the others was approximately 4.3 . Bacterial invasion into the dentinal tubules was observed in all but the S . salivarius group . Among the monoinfection groups, the S . sobrinus group showed the highest invasion rate, followed by the A . Viscosus group and the L . casei group . The invasion rate was also high in the mixed-infection groups . Immunohistochemical staining revealed invasion only by L . casei, and not by S . sobrinus and A . viscosus . The invasion rate by L . casei was higher in the mixed-infection group with either S . sobrinus or A . viscosus than in the monoinfection groups . These findings suggest that lactobacillus might play an important role in the initiation and progress of dentinal caries, and that this bacterial species might exhibit a cooperative cariogenicity when it coexists with other bacterial species that surpasses its individual cariogenicity. Gesundheitswesen, 1995 Nov, 57(11), 741 - 3 {What physicians should currently observe in the area of dental health}; Buttner M; Several factors govern the development of human dental caries . The actual caries incidence in children depends greatly on fluoride consumption, reduction of fermentable sugar intake (in favour of the use of sugar substitutes), dental health habits and regular dental check-ups . A significant reduction of dental caries in children and young adults is achieved in many countries following these principles . However, there remains a group, about 25%, with a particularly high incidence of caries . Today, efforts are directed at detecting these risk subjects . Mutans streptococci and lactobacilli are the main causative bacteria of human dental caries . The initiation of dental caries is preceded by colonisation of the dentition by S . mutans, usually in early childhood . The early establishment of these bacteria in the mouth of human infants is dependent on intrafamilial--mainly maternal--transmission of saliva . The higher the level of S . mutans in the maternal saliva, the more likely is the colonisation of primary dentition by cariogenic bacteria . The earlier the colonisation, the higher the incidence of caries . Today we have new diagnostic aids: Simple microbiological tests to detect the individuals with high salivary levels of these cariogenic bacteria, so called SM-millionaires . The tests are also a good educational aid for motivating patients to individual prophylaxis . What could a paediatrician or gynaecologist do to help the dentist? He could inform the parents early enough to avoid saliva contacts . For example, the mother should not take the child's spoon or pacifier in her mouth . The dentist meets the children much later, at an age where they already have caries . The older methods, mentioned at the begin, are also still valuable. J Dairy Res, 1995 Nov, 62(4), 611 - 20 Immunological and electrophoretic study of the proteolytic enzymes from various Lactococcus and Lactobacillus strains; Sasaki M et al.; Cell extracts of various lactobacilli and two Lactococcus strains were investigated for their immunoresponse with monoclonal and polyclonal antibodies raised against various proteolytic enzymes from Lc . lactis . Except for Lactobacillus casei SBT 2233, none of the lactobacilli proteins showed immunoresponse with the monoclonal antibodies . With polyclonal antibodies raised against aminopeptidases N and C and endopeptidase of Lc . lactis an immunoresponse was observed . However, the molecular masses of the reactive bands on the blot were considerably different from those of the corresponding lactococcal peptidases, except for the band that reacted with polyclonal antibodies against aminopeptidase C . The polyclonal antibodies raised against X-prolyl-dipeptidyl aminopeptidase and tripeptidase did not show any immunoreaction . As a control, all antibodies reacted with the lactococcal proteins on the blot, with molecular masses corresponding to those reported for the proteinases and peptidases . The results clearly showed that most of the proteolytic enzymes of lactobacilli were immunologically different from those of lactococci . The proteolytic enzymes in the cell-free extracts were separated by non-denaturing PAGE and visualized by zymogram staining . The electrophoretic pattern of the proteolytic enzymes of lactobacilli was different from that of Lc . lactis . Both experiments indicate that the enzymes of the proteolytic system of lactobacilli are different from those of lactococci. J Dairy Res, 1995 Nov, 62(4), 601 - 10 Comparison of proteolytic activities in various lactobacilli; Sasaki M et al.; A total of 169 Lactobacillus strains from 12 species (Lb . acidophilus, Lb . brevis, Lb . buchneri, Lb . casei, Lb . delbrueckii subsp . bulgaricus, Lb . delbrueckii subsp . delbrueckii, Lb . delbrueckii subsp . lactis, Lb . fermentum, Lb . helveticus, Lb . paracasei subsp . paracasei, Lb . plantarum and Lb . rhamnosus), isolated from raw milk and various milk products, and 9 Lactococcus lactis strains were evaluated for peptidase activities with five chromogenic substrates and a tryptic digest of casein . Within each species, the peptidase activity of the cell-free extracts of the strains varied . Furthermore, differences were observed between the Lactobacillus species and Lc . lactis . Lb . helveticus had by far the highest hydrolysing activities towards all substrates, indicating the presence of powerful aminopeptidases, X-prolyl-dipeptidyl aminopeptidases and proline iminopeptidases . Lb . delbrueckii subsp . bulgaricus possessed high hydrolysing activities towards substrates containing proline, alanyl-prolyl-p-nitroanilide and prolyl-p-nitroanilide . On the other hand, Lb . fermentum and Lb . brevis could be considered as weakly proteolytic species . A more detailed study with highly proteolytic Lactobacillus strains indicated that at least three different proteinases or endopeptidases were present . Compared with Lc . lactis, the Lactobacillus strains had a much lower hydrolytic action on glutamyl-glutamic acid, suggesting that glutamyl aminopeptidase was absent in lactobacilli. J Appl Bacteriol, 1995 Nov, 79(5), 506 - 12 The antimicrobial activity of lactic acid bacteria from fermented maize (kenkey) and their interactions during fermentation; Olsen A et al.; A total of 241 lactic acid bacteria belonging to Lactobacillus plantarum, Pediococcus pentosaceus, Lactobacillus fermentum/reuteri and Lactobacillus brevis from various processing stages of maize dough fermentation were investigated . Results indicated that each processing stage has its own microenvironment with strong antimicrobial activity . About half of the Lact . plantarum and practically all of the Lact . fermentum/reuteri investigated were shown to inhibit other Gram-positive and Gram-negative bacter