J Bacteriol, 1998 Aug, 180(15), 4011 - 4 Functional expression in Lactobacillus plantarum of xylP encoding the isoprimeverose transporter of Lactobacillus pentosus; Chaillou S et al.; The xylP gene of Lactobacillus pentosus, the first gene of the xylPQR operon, was recently found to be involved in isoprimeverose metabolism . By expression of xylP on a multicopy plasmid in Lactobacillus plantarum 80, a strain which lacks active isoprimeverose and D-xylose transport activities, it was shown that xylP encodes a transporter . Functional expression of the XylP transporter was shown by uptake of isoprimeverose in L . plantarum 80 cells, and this transport was driven by the proton motive force generated by malolactic fermentation . XylP was unable to catalyze transport of D-xylose. Eur J Clin Nutr, 1998 Jun, 52(6), 436 - 40 Effects of a milk product, fermented by Lactobacillus acidophilus and with fructo-oligosaccharides added, on blood lipids in male volunteers; Schaafsma G et al.; OBJECTIVE: To investigate in adult male volunteers the effect of a new fermented milk product, fermented by Lactobacillus acidophilus and with fructo-oligosaccharides added, on blood lipids . DESIGN: Randomized placebo-controlled double-blind two-way cross over trial with two treatment periods of three weeks, separated by a wash-out period of one week . SETTING: the study was performed at the TNO Nutrition and Food Research Institute in Zeist, The Netherlands . SUBECTS: Thirty normal healthy men, aged 33-64y (mean serum total cholesterol level: 5.23 +/- 1.03 (s.d.)), were selected for this study . Normal health was assessed by pre study screening . All subjects were used to an average Dutch food pattern . INTERVENTIONS: During the treatment periods subjects consumed three times daily a 125 ml of either test or reference product as a part of their habitual diet . The test product was a milk, fermented by yogurt starters and Lactobacillus acidophilus, and contained 2.5% fructo-oligosaccharides, 0.5% vegetable oil and 0.5% milk fat . The reference product was a traditional yogurt (milk fermented only by yogurt strains), containing 1% milk fat . Blood samples for serum lipid analysis and blood glucose measurements were taken before the start of the experiment and at the end of both treatment periods . RESULTS: As compared to the reference product, consumption of the test product resulted in significantly lower values for serum total cholesterol (P < 0.001), LDL-cholesterol (P < 0.005), and the LDL/HDL-ratio (P < 0.05) by 4.4, 5.4 and 5.3% respectively . Levels of serum HDL-cholesterol, triglycerides and blood glucose remained essentially unchanged . The beneficial effects of the test product on serum cholesterol were largely related to an increase of this parameter during the consumption of the reference product . CONCLUSIONS: As compared to traditional yogurt, daily consumption of three times 125 ml of test product specifically lowered serum LDL-cholesterol levels in normal healthy male adult subjects with borderline elevated levels of serum total cholesterol within three weeks. Oral Dis, 1998 Jun, 4(2), 114 - 9 Accumulation of strontium and fluoride in approximal dental plaque and changes in plaque microflora after rinsing with chlorhexidine-fluoride-strontium solution; Spets-Happonen S et al.; OBJECTIVES: To find out if strontium is incorporated into plaque and enamel in vivo during a 2-week rinsing period with a chlorhexidine-fluoride-strontium solution and to determine the effects of the rinsing on the numbers of mutans streptococci and lactobacilli in plaque . SUBJECTS AND METHODS: A total of 18 adult participants rinsed their mouths twice a day for 2 weeks, first with a placebo solution and subsequently, separated by a 1-week interval without rinsing, with a chlorhexidine gluconate (0.05%)-sodium fluoride (0.04%)-strontium (100 ppm as SrCl2) rinsing solution (CXFSr) for another 2 weeks . RESULTS: After the CXFSr rinsing period the strontium and fluoride contents (microgram g-1 plaque dry weight; mean +/- sr) of approximal plaque were 32.5 +/- 4.7 and 72.8 +/- 9.0, compared with the respective contents of 8.4 +/- 1.2 and 42.0 +/- 4.8 after placebo rinsing (P = 0.0001 for both comparisons) . The strontium content remained elevated for 6 weeks . The median proportion of mutans streptococci of approximal plaque of the total viable count of bacteria was 1% after placebo rinsing but decreased to 0.2% after CXFSr rinsing . The proportion of mutans streptococci remained low at 3 weeks (P = 0.018 vs placebo) but had reached the placebo level at 6 weeks . Rinsing with CXFSr solution did not reduce lactobacilli in plaque . The strontium or fluoride contents of the enamel surfaces subjected to tooth brushing did not significantly change . CONCLUSIONS: Strontium and fluoride accumulated in dental plaque during a 2-week CXFSr rinsing period and the proportion of mutans streptococci in approximal plaque was reduced at least for 3 weeks after completion of the rinsing. J Allergy Clin Immunol, 1998 Jul, 102(1), 57 - 64 Heat-killed Lactobacillus plantarum L-137 suppresses naturally fed antigen-specific IgE production by stimulation of IL-12 production in mice; Murosaki S et al.; BACKGROUND: Food allergy is caused by production of IgE against dietary antigen induced by T(H2) response . IL-12 inhibits T(H2) responses and strongly suppresses IgE production . We have recently established a murine model for IgE production with a predominant T(H2) response induced by feeding antigen . OBJECTIVE: We here show a suppressive effect of heat-killed Lactobacillus plantarum L-137, a potent inducer of IL-12, on IgE production against naturally fed antigen in a murine model . METHODS: The ability of L . plantarum L-137 to induce IL-12 production was examined in vitro and in vivo . DBA/2 mice were fed a casein diet and injected intraperitoneally with L . plantarum L-137 from the beginning of feeding or 2 weeks later . Recombinant mouse IL-12 was also injected 2 weeks after the start of feeding . Casein-specific IgE and IgG1 in plasma were determined by ELISA . RESULTS: L . plantarum L-137 directly induced IL-12 production by the peritoneal macrophages and also stimulated spleen cells to produce both IL-12 and interferon-gamma in vitro . In vivo treatment of L . plantarum L-137 also increased the plasma level of IL-12 in mice . Plasma anti-casein IgG1 and IgE levels were gradually elevated in DBA/2 mice fed a casein diet . Administration of L . plantarum L-137 from the beginning of feeding suppressed the elevation of anti-casein IgE levels, whereas the levels of anti-casein IgG1 were rather augmented by L . plantarum L-137 . IL-12 production of the peritoneal macrophages was enhanced, but IL-4 production of concanavalin A (Con A)-stimulated spleen cells was suppressed in the L . plantarum L-137-treated mice compared with control mice fed a casein diet . When L . plantarum L-137 was given from 2 weeks after the start of feeding, anti-casein IgE levels were also significantly suppressed, which was similar to the result found in mice treated with IL-12 . CONCLUSION: Our results suggest that L . plantarum L-137, a potent IL-12 inducer, is useful for prevention and treatment of food allergy. Cryobiology, 1998 Jun, 36(4), 315 - 9 Survival Rate and Enzyme Activities of Lactobacillus acidophilus Following Frozen Storage; Fernandez Murga ML et al.; The ability of two strains of Lactobacillus acidophilus, CRL 640 and CRL 800, to survive and retain their biological activities under frozen storage was determined . Freezing and thawing, as well as frozen storage, damaged the cell membrane, rendering the microorganisms sensitive to sodium chloride and bile salts . Both lactic acid production and proteolytic activity were depressed after 21 days at -20 degreesC, whereas beta-galactosidase activity per cell unit was increased . Cell injury was partially overcome after repair in a salt-rich medium . AIDS, 1998 Jul 9, 12(10), 1129 - 38 Preclinical studies on thiocarboxanilide UC-781 as a virucidal agent; Balzarini J et al.; BACKGROUND: Thiocarboxanilide UC-781 is a highly potent and selective non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1, which also has virucidal properties . Recent studies have shown that UC-781 would seem an ideal candidate for application as a vaginal virucide . OBJECTIVE: To investigate the antiviral potency and stability of UC-781 in a lipophilic gel formulation . METHODS: UC-781 was formulated in replens gel at different concentrations and administered intravaginally to rabbits at 5% in replens gel for 10 days . UC-781 was also exposed to temperatures of 4, 37 and 50 degrees C, and to low pH (6.0, 4.3, 2.0 and 1.2) . A number of microorganisms were exposed in culture to serial dilutions of UC-781 . RESULTS: The drug was stable under low pH conditions and did not lose its antiviral potency upon 4 h exposure to pH 3.5 (the estimated vaginal pH) . UC-781 can be easily formulated into a lipophilic gel (replens; up to 5%) and proved fully stable at 50 degrees C for 30 days . There was no effect on the growth of microorganisms (i.e., Candida and Lactobacillus strains) that are present in the vaginal flora . Neither systemic side-effects, nor local inflammation or damage of the vaginal mucosa or epithelium were observed in rabbits to which 5% UC-781 in replens gel had been administered . UC-781, formulated as 0.5, 0.2 and 0.05% replens gel, and UC-38, alpha-APA and zidovudine, formulated as 0.5 or 0.2% replens gel, were effective in protecting CEM cells in the very beginning against productive HIV-1 replication . This points to an efficient diffusion of the drugs from the lipophilic gel to the hydrophilic culture medium . However, subsequent subcultivations at a dilution rate of 1:10 every 3-4 days resulted in a rapid breakthrough of virus with all drugs except UC-781 in its 0.5 and 0.2% gel formulation . These cultures were fully protected against HIV-1 and remained completely cleared from virus for at least 10 subcultivations . CONCLUSIONS: The virus that emerged under 0.05% UC-781 remained highly sensitive to the NNRTI, including UC-781, in cell culture, suggesting a lack of resistance development under our experimental conditions. J Appl Microbiol, 1998 May, 84(5), 698 - 702 Lactobacillus kunkeei sp . nov.: a spoilage organism associated with grape juice fermentations; Edwards CG et al.; A Gram-positive rod was isolated from a commercial grape wine undergoing a sluggish/stuck alcoholic fermentation . The organism produced L-lactic acid from glucose, possessed weak catalase activity, and fermented relatively few carbohydrates, i.e . glucose, fructose, sucrose, raffinose (weakly) and mannitol . The 16S rRNA gene sequence analysis revealed that the isolate was phylogenetically a member of the genus Lactobacillus and formed a distinct subline within the Lact . casei cluster of species . Based on phenotypic and phylogenetic evidence, a new species is proposed, Lact . kunkeei . The type strain of Lact . kunkeei is ATCC 700308. Community Dent Oral Epidemiol, 1998 Jun, 26(3), 170 - 6 Factors associated with caries incidence in an elderly population; Powell LV et al.; The purpose of this paper was to identify baseline factors associated with future caries development in older adults (age 60+) during a 3-year study period . Poisson regression analysis was used to determine the association between potential risk factors and disease incidence . The significant factors associated with high coronal caries incidence rates were high baseline root DMFS (P<0.001), high counts of mutans streptococci and lactobacilli (P=0.036), male gender (P=0.007), and Asian ethnicity (P=0.002) . These factors had small to moderate effects on incidence rates, with relative risk values of approximately 1.2 to 2 . The significant factors associated with higher disease incidence on root surfaces were baseline coronal DMFS (marginally significant, P=0.078), high bacterial counts (P=0.002), and Asian ethnicity (P=0.009) . The predictive value of the models was low for both coronal and root caries . This result may be because this population had a higher than usual caries incidence rate, making discrimination among these caries-active individuals difficult . The current study affirmed the value of baseline DMFS and salivary variables to modeling caries incidence and introduced ethnicity as a variable useful for the study of dental caries in older adults. Acta Odontol Scand, 1998 Apr, 56(2), 70 - 5 A 3-year clinical evaluation of two composite resins in class-II cavities; Rasmusson CG et al.; The purpose of this investigation was to study the clinical performance of a new system with a proposed expanding liner for composite restorations introduced in the late 1980s . The present study reports on baseline data and the result after 3 years . One hundred and four class-II cavities in 95 patients were alternatively restored by Superlux Molar and the reference material P-50 APC by 12 general practitioners in 3 public dental health clinics . After 3 years 82 restorations (79%) were available for examination . The restorations were evaluated on the basis of USPHS criteria after 1 week and again after 3 years . Stone casts were used to quantitatively categorize wear in accordance with the Leinfelder method . Color slides and bitewings were taken to supplement the clinical evaluation of color match and marginal adaptation, respectively, and secondary caries . The failure rate (USPHS rating, Charlie) was four restorations of Superlux Molar and seven of P-50 APC . The average wear after 3 years of Superlux Molar was 131 microm and of P-50 APC, 128 microm . There were no statistically significant differences between the two materials with regard to, for example, handling characteristics, anatomic form, color match, marginal discoloration, or failures . A significantly higher wear rate was found after 3 years in patients with a high level of salivary lactobacilli (> 10(5) colony-forming units (CFU)/mL at base line) compared with those with lower levels . This suggests that an acidic environment might enhance the wear rate. Acta Odontol Scand, 1998 Apr, 56(2), 65 - 9 Betaine-containing toothpaste relieves subjective symptoms of dry mouth; Soderling E et al.; Subjects with dry mouth often experience irritation of the oral mucosa when using sodium lauryl sulfate containing products for oral hygiene . Betaine, or trimethylglycine, reduces skin-irritating effects of ingredients of cosmetics such as sodium lauryl sulfate . The aim of the present study was to compare the effects of a betaine-containing toothpaste with a regular toothpaste on the oral microbial flora, the condition of the oral mucosa, and subjective symptoms of dry mouth in subjects with chronic dry mouth symptoms . Thirteen subjects with chronic dry mouth symptoms and with a paraffin-stimulated salivary flow rate < or = 1 mL/min participated in the double-blind crossover study . Ten subjects had a very low salivary flow rate (< or = 0.6 mL/min) . The subjects used both experimental toothpastes (with or without 4% betaine) twice a day for 2 weeks . Oral examinations and microbiologic sample collections were made at the base lines preceding the two experimental periods and at the end . Standardized questions on subjective symptoms of dry mouth were used when the subjects were interviewed at the end of the two experimental periods . No study-induced significant changes were observed in the microbiologic variables (plaque index, mutans streptococci, lactobacilli, Candida species) or in the appearance of the oral mucosa . The use of the betaine-containing toothpaste was, however, associated with a significant relief of several subjective symptoms of dry mouth . Betaine appears thus to be a promising ingredient of toothpastes in general and especially of toothpastes designed for patients with dry mouth. Eur J Clin Microbiol Infect Dis, 1998 Mar, 17(3), 203 - 5 Use of 16S rRNA gene sequencing to identify Lactobacillus casei in septicaemia secondary to a paraprosthetic enteric fistula; Parola P et al.; Human infections caused by Lactobacillus spp . are rarely reported in the literature . Underlying conditions are frequently reported, and identification of lactobacilli to the species level remains rare . A case of Lactobacillus casei septicaemia secondary to a vascular graft infection is reported . The 16S rRNA sequencing technique was used to definitively identify Lactobacillus casei. Zh Mikrobiol Epidemiol Immunobiol, 1998 Mar-Apr, (2), 102 - 4 {Development of methods for the stabilization of biomass in the preparation of medicinal forms of lactobacterin}; Neschisliaev VA et al.; In this work the problems of obtaining medicinal forms of lactobacterin with the use of nontraditional methods for the stabilization of biomass are considered . The data on the stability of tablets, suppositories and microgranules of the preparation prepared on the basis of immobilized cells, are presented. Carbohydr Res, 1998 Feb, 307(1-2), 125 - 33 Structural analysis of the exopolysaccharides produced by Lactobacillus spp . G-77; Duenas-Chasco MT et al.; The exopolysaccharide produced by a ropy strain of Lactobacillus spp . G-77 in a semi-defined medium, was found to be a mixture of two homopolymers composed of D-Glc . The two poly-saccharides were separated and, on the basis of monosaccharide and methylation analyses, 1H, 13C, 1D and 2D NMR experiments, one of the polysaccharides was shown to be a 2-substituted-(1-3)-beta-D-glucan, identical to that described for the EPS from Pediococcus damnosus 2.6 (M.T . Duenas-Chasco, M.A . Rodriguez-Carvajal, P . Tejero-Mateo, G . Franco-Rodriguez, J . L . Espartero, A . Irastorza-Iribar, and A.M . Gil-Serrano, Carbohydr . Res., 303 (1997) 453-458), and the other polysaccharide was shown to consist of repeating units with the following structure {formula: see text} Biochemistry, 1998 Jul 7, 37(27), 9704 - 15 Structural and enzymatic studies of a new analogue of coenzyme B12 with an alpha-adenosyl upper axial ligand; Brown KL et al.; A new analogue of coenzyme B12 (5'-deoxyadenosylcobalamin, AdoCbl), in which the configuration of the N-glycosidic bond in the Ado ligand is inverted {(alpha-ribo)AdoCbl}, has been synthesized and its crystal structure determined by X-ray diffraction {MoKalpha, lambda = 0.71073 A, monoclinic P212121, a = 16.132(12) A, b = 21 . 684(15) A, c = 27.30(3) A, 9611 independent reflections, R1 = 0 . 0708} . As suggested by molecular mechanics modeling before the structure was known, the Ado ligand lies over the southern quadrant of the molecule, as is the case for AdoCbl . The most striking feature of the structure is disorder in the orientation of the adenine (Ade) moiety relative to the ribose of the Ado ligand . This was resolved with a two-state model in which in the major (0.57 occupancy) conformer the A16(O)-A11-A9(N)-A8 dihedral angle is 1.9 degrees and the Ade is virtually perpendicular to the corrin ring; in the minor conformer, the Ade is tilted down, and this dihedral is -48.7 degrees . The Co-C and axial Co-N bond lengths and the Co-C-C bond angle are quite similar to those in AdoCbl . The corrin ring is considerably flatter than that of AdoCbl, with a fold angle of 11.7 degrees . The molecule was successfully modeled by molecular mechanics (MM), and rotation of the Ado ligand relative to the corrin gave rise to four locally minimum structures with the Ado in the southern, eastern, northern, or western quadrant, with the southern conformation as the global minimum, as is the case with AdoCbl itself . Nuclear Overhauser effects (nOe's) observed by two-dimensional (2D) NMR were incorporated as restraints in molecular dynamics (MD) and simulated annealing (SA) calculations . A MD simulation at 300 K showed that only the southern conformation is populated with the Ado ligand confined to an arc from over C15 to over C12, while the Ade ring oscillates from perpendicular to parallel to the corrin ring . Twenty-seven structures were collected by MD-SA . Most of these annealed into the southern conformation, but examples of the other conformations were also found . The new analogue is a partially active coenzyme for the ribonucleotide reductase from Lactobacillus leichmanii with maximal activity that is 9.7% of that of AdoCbl itself, and a very high Km value (245 microM compared to 0.54 microM for AdoCbl) . In addition, the rate constant for enzyme-induced carbon-cobalt bond cleavage of (alpha-ribo)AdoCbl is 160-fold smaller than that for AdoCbl, and only 1/3 as much cob(II)alamin is produced at the active site. Food Chem Toxicol, 1998 Apr, 36(4), 321 - 6 Ability of dairy strains of lactic acid bacteria to bind a common food carcinogen, aflatoxin B1; El-Nezami H et al.; This study was conducted to examine the ability of selected dairy strains of lactic acid bacteria to remove aflatoxin B1 (AFB1) from liquid media . Both Lactobacillus rhamnosus strain GG (LBGG) and L . rhamnosus strain LC-705 (LC705) can significantly (P > 0.05) remove AFB1 when compared with that by other strains of either Gram-positive or Gram-negative bacteria . Removal of AFB1 by LBGG and LC705 was a rapid process with approximately 80% AFB1 removed at 0 hr . Removal of AFB1 by these two strains was both temperature and bacterial concentration dependent. Biosci Biotechnol Biochem, 1998 May, 62(5), 887 - 92 Sequence analysis by cloning of the structural gene of gassericin A, a hydrophobic bacteriocin produced by Lactobacillus gasseri LA39; Kawai Y et al.; Gassericin A, a bacteriocin from Lactobacillus gasseri LA39, was purified to homogeneity from the culturesupernatant mainly by reverse-phase chromatography . The molecular weight of gassericin A was found to be 5,652 by mass analysis, unlike the estimated 3,800 found by SDS-PAGE . However, when the purified preparation was treated with lysylendopeptidase, it migrated as a single band to 5,600 with bacteriocin activity on SDS-PAGE . N- and C-terminal amino acids could not be identified . The internal amino acid could be identified after gassericin A was hydrolyzed with lysylendopeptidase . The DNA of the structural gene of gassericin A was sequenced by cloning of the gene from chromosomal DNA with an oligonucleotide probe . The structural gene of gassericin A was found on the chromosomal DNA as an open reading frame encoding a protein composed of 91 amino acids . The amino acid sequence of mature gassericin A was predicted to be 58 residues from the DNA sequence and results of mass analysis . These results suggested that gassericin A has a closed circular structure with N- and C-terminals linked . Gassericin A is a hydrophobic class II bacteriocin; it was 98% identical with acidocin B produced by Lactobacillus acidophilus M46. Appl Environ Microbiol, 1998 Jul 1, 64(7), 2616 - 23 Modeling of Growth of Lactobacillus sanfranciscensis and Candida milleri in Response to Process Parameters of Sourdough Fermentation; Ganzle MG et al.; We investigated the effect of the ecological factors pH, temperature, ionic strength, and lactate, acetate, and ethanol levels on Candida milleri and two strains of Lactobacillus sanfranciscensis, organisms representative of the microflora of sourdough . A mathematical model describing the single and combined effects of these factors on the growth of these organisms was established in accordance with the following criteria: quality of fit, biological significance of the parameters, and applicability of the in vitro data to in situ processes . The growth rates of L . sanfranciscensis LTH1729 and LTH2581 were virtually identical under all conditions tested . These organisms tolerated >160 mmol of undissociated acetic acid per liter . Growth occurred in the pH range of 3.9 to 6.7 and was completely inhibited by 4% NaCl . C . milleri had a lower optimum temperature for growth (27 degreesC) than the lactobacilli . The growth of the yeast was not affected by pH in the range of 3.5 to 7, and up to 8% NaCl was tolerated . Complete inhibition of growth occurred at 150 mmol of undissociated acetic acid per liter, but acetate at concentrations of up to 250 mmol/liter exerted virtually no effect . The model provides insight into factors contributing to the stability of the sourdough microflora and can facilitate the design of novel sourdough processes. Appl Environ Microbiol, 1998 Jul 1, 64(7), 2418 - 23 Differentiation of Lactobacillus Species by Molecular Typing; Zhong W et al.; A total of 64 type, reference, clinical, health food, and stock isolates of microaerophilic Lactobacillus species were examined by restriction fragment length polymorphisms . Of particular interest were members of six of the eight species most commonly recovered from the vaginas of healthy premenopausal women, namely, Lactobacillus jensenii, L . casei, L . rhamnosus, L . acidophilus, L . plantarum, and L . fermentum . Six main groupings were identified on the basis of ribotyping . This technique was able to classify fresh isolates to the species level . In the case of the ribotype A grouping for L . rhamnosus, differences between strains were evident by chromosome typing (chromotyping) . Many isolates did not possess plasmids . Six L . rhamnosus strains isolated from four different health food products appeared to be identical to L . rhamnosus ATCC 21052 . The molecular typing system is useful for identifying and differentiating Lactobacillus isolates . Studies of strains of potential importance to the urogenital flora should include molecular characterization as a means of comparing genetic traits with those of strains whose characteristics associated with colonization and antagonism against pathogens have been defined. Dtsch Tierarztl Wochenschr, 1998 May, 105(5), 199 - 200 Colonization capability of orally administered Lactobacillus strains in the gut of gnotobiotic piglets; Nemcova R et al.; In the present study, the effect of Lactobacillus casei subsp . casei and Lactobacillus fermentum inoculation on jejunum and ileum colonization in gnotobiotic piglets has been observed . The characteristic features of the strains used were strong adherence to pig epithelial gut cells as well as inhibitory activity against enteropathogenic E . coli under in vitro conditions . Strains were inoculated to 2, 3, and 4 day old gnotobiotic piglets at a dose of 2 ml (1 x 10(8) germs/ml) . On the second day after the last inoculation, Lactobacillus casei subsp . casei strain counts adhered to the jejunum mucosa and those adhered to the ileum mucosa were 4.54 log 10.cm-2 and 5.40 log 10.cm-2, respectively . Lactobacillus fermentum counts adhered to the jejunum mucosa and those adhered to the ileum mucosa were 5.73 log 10.cm-2 and 4.01 log 10.cm-2, respectively . On day 5 after the last inoculation, the counts in both strains were by one log higher . The results obtained point out to the fact that Lactobacillus casei subsp . casei and Lactobacillus fermentum colonized the mucosa of both jejunum and ileum and survived in the intestinal tract . The adherence of lactobacilli to gut cells in vitro correlated with their capability to adhere to the mucosa of both jejunum and ileum in vivo. J Bacteriol, 1998 Jul, 180(13), 3474 - 6 Identification of the repressor-encoding gene of the Lactobacillus bacteriophage A2; Ladero V et al.; The repressor gene of the Lactobacillus phage A2 has the following properties: it (i) encodes a 224-residue polypeptide with DNA binding and RecA cleavage motifs, (ii) is expressed in lysogenic cultures, and (iii) confers superinfection immunity on the host . Adjacent, but divergently transcribed, lies another open reading frame whose product resembles the lambda Cro protein . In the 161-bp intergenic segment, putative promoters and operators have been detected. J Bacteriol, 1998 Jul, 180(13), 3400 - 4 Expression of the bglH gene of Lactobacillus plantarum is controlled by carbon catabolite repression; Marasco R et al.; A newly identified bglH gene coding for a phospho-beta-glucosidase of Lactobacillus plantarum was isolated and expressed in Escherichia coli . The sequence analysis of the cloned DNA fragment showed an open reading frame encoding a 480-amino-acid protein with a calculated molecular mass of 53 kDa . The bglH gene was shown to be expressed on a monocistronic transcriptional unit . Its transcription was repressed 10-fold in L . plantarum cells grown on glucose compared to the beta-glucoside salicin as a sole carbon source . A catabolite-responsive element (CRE) spanning from -3 to +11 with respect to the transcriptional start point was found, and its functionality was assessed by mutational analysis . In vitro and in vivo DNA binding experiments suggested the occurrence of a DNA-protein complex at the CRE site, which would mediate glucose repression of bglH expression. Exp Parasitol, 1998 Jun, 89(2), 241 - 50 Trichomonas vaginalis: in vitro phagocytosis of lactobacilli, vaginal epithelial cells, leukocytes, and erythrocytes; Rendon-Maldonado JG et al.; This paper explores the interaction of two strains of Trichomonas vaginalis, of high and low virulence, with the cell types present in the microenvironment of the parasite during human infections . With the use of transmission and scanning electron microscopy the sequence of internalization by T . vaginalis of Doderlein's lactobacilli, and of vaginal epithelial cells, leukocytes, and erythrocytes was documented . Furthermore, the degradation of ingested material by colocalization of acid phosphatase activity in phagocytic vacuoles was demonstrated . Phagocytosis of all cell types analyzed was found in both strains studied, although the highly virulent strain internalized target cells more rapidly than the less virulent one . Ultrastructural evidence indicated that phagocytosis takes place through two distinct mechanisms, only one involving the formation of a phagocytic stoma, characteristic of professional phagocytes . T . vaginalis phagocytosis may be both an efficient means of obtaining nutrients for the parasite and a significant factor in the pathogenesis of trichomonal infections of the human genitourinary tract. J Endod, 1998 Apr, 24(4), 252 - 5 Stimulation of interleukin-6 production in human dental pulp cells by peptidoglycans from Lactobacillus casei; Matsushima K et al.; Interleukin-6 (IL-6), which is a multifunctional cytokine, has an important role in acute and chronic inflammation . The peptidoglycan (PG) was purified from Lactobacillus casei, which was a Gram-positive bacteria frequently isolated from deep carious lesions and suspected to be a pathogen of pulpitis . In this study, the effects of PG on the production of IL-6 in human dental pulp cells were examined . PG stimulated IL-6 production in a time- and dose-dependent manner . Reverse transcriptase-polymerase chain reaction experiments showed that the increase was dependent on the enhancement of IL-6 mRNA levels . These findings suggest that Gram-positive bacteria, such as L . casei, from carious lesions, might be involved in developing pulpitis through the stimulation of IL-6 production. Curr Microbiol, 1998 Jul, 37(1), 64 - 6 On the iron requirement of lactobacilli grown in chemically defined medium; Imbert M et al.; The iron requirement of four strains of lactobacilli (L . acidophilus, L . delbrueckii subsp . bulgaricus, L . plantarum, and L . pentosus) was studied in a synthetic medium under aerobic or anaerobic conditions . Effects of iron salt and iron-chelated compounds were tested on bacterial growth in manganese-free or -supplemented media . No significant growth stimulation was observed in any condition . These results support the absolute manganese requirement for optimum growth of lactobacilli and the needless incorporation of iron in growth media. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 1998 Jun, 85(6), 680 - 5 Caries in patients with non-insulin-dependent diabetes mellitus; Collin HL et al.; OBJECTIVE: The purpose of this study was to investigate the prevalence and risk factors of dental caries in patients with non-insulin-dependent diabetes mellitus and to determine whether these factors are associated with metabolic control and vascular complications of the disease . STUDY DESIGN: Both the occurrence of caries, acidogenic oral bacteria, and yeasts and salivary flow were studied in 25 patients with non-insulin-dependent diabetes mellitus whose diagnosis had been set 13 to 14 years earlier and in whom the metabolic evolution of the disease was well established . The patients' glycemic control was determined by means of analysis of the blood hemoglobin A1C concentration at the time of dental examination . The control group consisted of 40 nondiabetic subjects in the same age group . Decayed, missing, and filled teeth indices and numbers of surfaces with caries, filled surfaces, and root caries were determined by means of clinical dental caries examination . Stimulated salivary flow was measured, and levels of Streptococcus mutans, lactobacilli, and yeasts were analyzed . RESULTS: The median hemoglobin A1C concentration of the patients was 8.6%, which indicates poor metabolic control of diabetes . No association was found between the metabolic control of disease and dental caries . The occurrence of dental caries was not increased in the patients with non-insulin-dependent diabetes mellitus in comparison with the control subjects . The counts of acidogenic microbes and yeasts did not differ statistically significantly between the groups . There was no association of caries with the prevalence of coronary artery disease or hypertension in either the patients or the control subjects . In a stepwise logistic regression model, a salivary flow of at least 0.8 ml/min was related to the occurrence of dental caries in patients with non-insulin-dependent diabetes mellitus, whereas negligence with respect to dental care was the most important risk predictor in the control group . CONCLUSION: Our results showed no effect of diabetes on the prevalence of caries . However, the caries-protective effect of saliva was partly lost in patients with non-insulin-dependent diabetes mellitus. Int J Immunopharmacol, 1997 Sep-Oct, 19(9-10), 487 - 92 Clinical study of the effect of the preparation DEODAN on leukopenia, induced by cytostatics; Krusteva E et al.; The aim of the study is to establish the effect of the preparation DEODAN on leukopenia induced by chemotherapeutics in oncological patients . DEODAN is an oral preparation, obtained from lyzozyme lysates of Lactobacillus bulgaricus strain "I . Bogdanov patent strain tumoronecroticance B-51" ATCC 21815, called shortly LB51 . In the study there are included two groups of patients--from National Oncological Centre, Sofia, the other from Clinic of Medicine, Bertha Academic Hospital, Clinics of Duisburg, Duisburg . All the patients, (78) have undergone combined chemotherapy . In all patients, leukopenia has been established in moderate and medium levels . The scheme of the application of DEODAN has been 3 g, three times a day before meals, from the first day of establishing the disturbances of the haemopoesis . The treatment lasted until the restoration of the haematological values . Only DEODAN was applied . The results obtained show that the recovery of the WBC count (values above 3000) took place in all of the patients between days 3 and 5 . None of the patients displayed any infectious or febrile complications, as a result of the applied chemotherapy and the treatment with the preparation . DEODAN also improves the general condition of the patients. Biochemistry, 1998 Jun 23, 37(25), 9038 - 42 Aspartate 221 of thymidylate synthase is involved in folate cofactor binding and in catalysis; Chiericatti G et al.; Structural studies indicate that Asp 221 of Lactobacilluscasei thymidylate synthase forms a hydrogen bond network with the 2-amino and 3-imino groups of the folate {Matthews, D . A . (1990) J . Mol . Biol . 214, 937-948; Finer-Moore, J . S . (1990)Biochemistry 29, 6977-6986} that has been proposed to participate in catalysis . We prepared a complete replacement set of 19 mutants at position 221 of L . casei thymidylate synthase . Of these, the only one with sufficient activity to complement growth of a thymidylate synthase-deficient host was the Cys mutant . To further elucidate the function of the Asp 221 side chain, seven thymidylate synthase 221 mutants were studied in detail with regard to catalysis of dTMP formation and of thymidylate synthase partial reactions . Most of the mutants bound the nucleotide substrate dUMP with only moderate loss of binding affinity, indicating that the Asp side chain does not contribute to dUMP binding . Most of the mutants catalyzed the cofactor-independent dehalogenation of 5-bromodUMP; hence, the Asp side chain of TS is not essential for addition of the catalytic Cys residue to the nucleotide substrate . Mutants showed decreased affinity for the folate cofactor, but those with side chains capable of hydrogen bond formation were less severely affected . Some of the mutants were capable of forming covalent thymidylate synthase-5-fluorodUMP-methylenetetrahydrofolate complex; hence, the Asp side chain is not essential for steps leading to the covalent complex . We conclude that the hydrogen bond network between Asp 221 and the folate cofactor contributes to cofactor binding and a catalytic step after formation of the covalent ternary complex intermediate. J Appl Microbiol, 1998 Apr, 84(4), 649 - 60 Evaluation of the extent and type of bacterial contamination at different stages of processing of cooked ham; Samelis J et al.; In an attempt to determine the composition and origin of the spoilage flora of refrigerated vacuum-packed cooked ham, the changes in microbial numbers and types were followed along the processing line . Results revealed Lactobacillus sake and Leuconostoc mesenteroides ssp . mesenteroides as the major causative agents of spoilage of sliced ham stored at 4 degrees C and 12 degrees C, due to recontamination in the cutting room . On the contrary, the progressive deterioration of whole ham under the same storage conditions was associated with a non-identifiable group of leuconostoc-like bacteria . Except for lactic acid bacteria, no other organism grew in vacuum packs of either sliced or whole ham . Although atypical leuconostocs could not be detected among isolates recovered from freshly produced whole ham, they appeared to survive cooking and proliferate during storage . Neither these organisms however, nor Lact . sake and Leuc . mesenteroides were important in curing and tumbling as carnobacteria, mainly Carnobacterium divergens, and Brochothrix thermosphacta dominated at this stage . A progressive inversion of the ham microflora from mostly Gram-negative at the beginning of processing to highly Gram-positive prior to cooking was noted . Listeria monocytogenes cross-contaminated ham during tumbling . However, the pathogen was always absent from the vacuum-packed product provided that heating to a core temperature of 70 degrees C occurred and recontamination during slicing and packing was prevented . The percentage distribution of different species of lactic acid bacteria as well as the uncommon phenotypic characteristics of some strains were discussed. J Appl Microbiol, 1998 Apr, 84(4), 600 - 6 Characterization of Lactobacillus sake isolates from dry-cured sausages by restriction fragment length polymorphism analysis of the 16S rRNA gene; Sanz Y et al.; Lactobacillus sake strains originally isolated from dry-fermented sausages were characterized by phenotypic and genotypic methods, including DNA-DNA hybridization, restriction fragment length polymorphism (RFLP), and 16S rDNA sequencing analysis, in order to establish their taxonomic position and relation to well defined reference species . Initially, isolates of Lact . sake showing a characteristic phenotype (melibiose-positive, maltose- and arabinose-negative) were identified by DNA-DNA hybridization . Subsequently, RFLP studies using EcoRI and HindIII as restriction enzymes, and cDNA from Escherichia coli or 16S rDNA from Lact . sake strains as probes, showed distinct polymorphism levels . Thus, EcoRI-digested DNA probed with cDNA from E . coli disclosed the presence of a unique cluster for the meat isolates tested, allowing their differentiation from the reference type strain . When HindIII-digested DNA was hybridized with the cDNA probe, strain-specific patterns were obtained, showing a higher discrimination power . Considerable strain differentiation was also observed when EcoRI and HindIII digests were hybridized with 16S rDNA probes . Finally, sequence analysis of the 16S rDNA from one isolate also revealed a certain degree of genetic variability with respect to the reference strain of Lact . sake. J Appl Microbiol, 1998 Feb, 84(2), 207 - 12 QSARs for the effect of benzaldehydes on foodborne bacteria and the role of sulfhydryl groups as targets of their antibacterial activity; Ramos-Nino ME et al.; Quantitative structure activity relationships (QSARs) were obtained describing the activity of a series of benzaldehydes against three different foodborne bacteria, Listeria monocytogenes F6861, serotype 4b, Salmonella enteritidis, Phage type 4, P167807 and Lactobacillus plantarum INT.L11 . MIC values at pH 6.2 and 35 degrees C were obtained for 11 phenolic benzaldehydes to produce multiple linear regression and artificial neural network models . For each organism, the models contained a steric parameter Vw and an electronic-steric parameter for ortho substituents Es degree . The benzaldehydes did not require to partition to produce their effect, shown by the lack of a lipophilic parameter in the models . This strongly suggests that they act on the outside of the cells . Substitution ortho to the carbonyl group increased their antibacterial action . Cells were treated with 2,3-dihydroxy benzaldehyde and examined for their ability to bind radiolabelled iodoacetate to envelope sulfhydryl groups that remained available . It was shown that the accumulation of radiolabelled iodoacetate was lower after treatment, indicating possible competition between these two compounds for the same target . The order of the sensitivity to benzaldehydes (Salmonella > Listeria > Lactobacillus) correlated with the number of surface sulfhydryl groups available, being highest for Salmonella. Lett Appl Microbiol, 1998 Apr, 26(4), 248 - 52 A method for the selective enumeration and isolation of ruminal Lactobacillus and Streptococcus; Yanke LJ et al.; Ruminal lactic acid-producing bacteria were selectively isolated and enumerated using a one hour aerobic exposure prior to incubation on a semi-selective Lactobacillus medium, MRS, under anaerobic conditions . The technique allowed growth of pure cultures of ruminal Lactobacillus spp . and Streptococcus bovis without supporting the growth of pure cultures of any of the prominent ruminal bacterial species . In mixed cultures, the one hour aerobic pre-incubation inhibited the growth of the obligate anaerobic ruminal bacteria which can otherwise grow on the MRS medium, and the subsequent anaerobic incubation permitted maximal recovery of the weakly aerotolerant ruminal lactic acid-producing Lactobacillus spp . and Streptococcus spp . The efficacy of this technique in selecting exclusively for the lactic acid-producing bacteria was also demonstrated from populations of rumen bacteria from mixed culture end-point in vitro fermentation, continuous in vitro culture and isolations from fresh ruminal samples. Int J Food Microbiol, 1998 May 5, 41(1), 45 - 51 Adhesion of some probiotic and dairy Lactobacillus strains to Caco-2 cell cultures; Tuomola EM et al.; The adhesion of 12 different Lactobacillus strains was studied using Caco-2 cell line as an in vitro model for intestinal epithelium . Some of the strains tested have been used as probiotics, and most of them are used in the dairy and food industry . Human and bovine enterotoxigenic Escherichia coli strains were used as positive and negative control, respectively . Bacterial adhesion to Caco-2 cell cultures was quantitated using radiolabelled bacteria . The adherence of bacteria was also observed microscopically after Gram staining . Viability of bacteria prior to adhesion was verified using flow cytometry . Among the tested strains, L . casei (Fyos) was the most adhesive strain and L . casei var . rhamnosus (Lactophilus) was the least adhesive strain, approximately 14 and 3% of the added bacteria adhered to Caco-2 cell cultures, respectively . The corresponding values for positive and negative control E . coli strains were 14 and 4%, respectively . The Lactobacillus strains tested could not be divided into distinctly adhesive or non-adhesive strains, since there was a continuation of adhesion rates . The four most adhesive strains were L . casei (Fyos), L . acidophilus 1 (LC1), L . rhamnosus LC-705 and Lactobacillus GG (ATCC 53103) . No significant differences in the percentage adhesion were observed between these strains . Adhesion of all the strains was dependent on the number of bacteria used, since an approximately constant number of Caco-2 cells was used, indicating that the Caco-2 cell binding sites were not saturated . Viability of bacteria was high since approximately 90% of the bacteria were viable with the exception of L . acidophilus 1 which was 74% viable . Microscopic evaluations agreed with the radiolabelled binding as evidenced by observing more bacteria in Gram-stained preparations of good adhering strains compared to poorly adhering strains. Int J Food Microbiol, 1998 May 5, 41(1), 1 - 7 Effect of intestinal Lactobacillus starter cultures on the behaviour of Staphylococcus aureus in fermented sausage; Sameshima T et al.; The effects of Lactobacillus strains isolated from intestinal tracts for starter cultures of fermented sausage on the growth rate and enterotoxin production of Staphylococcus aureus were studied at two fermentation temperatures of 20 degrees C and 35 degrees C . Initial inoculated populations in the sausage batter were approx . 10(4) cfu/g for S . aureus and 10(7) cfu/g for the Lactobacillus strain as a starter culture . Samples of sausage were taken during fermentation and analyzed for pH and microbial populations . In control lots without inoculation of Lactobacillus strains, staphylococcal enterotoxin was detected during fermentation at each temperature . Of three intestinal Lactobacillus strains, L . rhamnosus FERM P-15120 and L . paracasei subsp . paracasei FERM P-15121 inhibited the growth and enterotoxin production of S . aureus in sausages during fermentation at both temperatures, although L . acidophilus FERM P-15119 could not satisfactorily suppress them . The effect of the two selected strains in meat fermentation (i.e., fermentation time, acid production, inhibition of S . aureus) was the same as that of a commercial L . sake starter culture for fermented sausage . These results suggest the intestinal Lactobacillus strains selected in this study could be utilized as a starter culture to produce new fermented meat products that are microbiologically safe. Folia Med (Plovdiv), 1998, 40(1), 34 - 40 Clinical manifestations and diagnosis of bacterial vaginosis in a clinic of sexually transmitted diseases; Tchoudomirova K et al.; BACKGROUND: The aim of the present study was to evaluate the prevalence of bacterial vaginosis (BV) and correlate it with the data from the patient history and clinical manifestations in women attending an STD clinic and to compare two methods of diagnosis . MATERIAL AND METHODS: On hundred and fifty-six women, aged 15 to 45, attending the STD clinic of the Higher Medical Institute in Plovdiv, Bulgaria were enrolled in the study . All women were evaluated for the presence of BV using standard criteria and Gram stain of vaginal secretions . Symptoms, clinical manifestations, methods of contraception and sexual life and smoking were analyzed . RESULTS: Using clinical criteria and Gram's stain, BV was diagnosed in 59 women (37.8%) . BV was associated with age younger than 25 years, risk sexual behaviour, e.g . lack of a permanent sexual partner during the preceding 6 months, use of an intrauterine device, other STDs and smoking . Symptoms are not a reliable way of diagnosing BV, but the presence of a homogeneous vaginal discharge on examination, a positive amine test and pH > or = 4.7 are common in BV . A negative correlation was found between the number of lactobacilli and BV . CONCLUSIONS: BV is common in women attending STD clinic and is associated with other STDs, e.g . infection with Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, human papilloma virus . The Gram stain method is inexpensive and easy to perform for the laboratory diagnosis of BV; it can be used reliably as an indicator of the changes preceding BV. Biotechnol Prog, 1998 May, 14(3), 537 - 9 Combined influence of growth and drying conditions on the activity of dried lactobacillus plantarum Linders LJM, Kets EPW, de Bont JAM, van't Riet K. The production of active dried starter cultures can be influenced at several levels in the production process . In this paper the following process factors are discussed: osmotic stress during growth and cell density prior to drying . Contradicting results are reported in the literature on the influence of osmotic stress during growth on the residual activity after drying . The combined approach in which two process factors were studied at a time resulted in an explanation for the discrepancy in earlier work . The cell density prior to drying had an important influence on the glucose fermenting activity after drying . Residual activities ranging from 0.10 to 0.83 were achieved using initial cell densities between 0.025 and 0.23 g of cell/g of sample, respectively . The drying tolerance of cells grown with osmotic stress of 1 M NaCl was low (residual activity = 0 . 06) and was not related to the cell density prior to drying . The influence of osmotic stress during growth on the drying tolerance of Lactobacillus plantarum was dependent on the cell density prior to drying. Proc Natl Acad Sci U S A, 1998 Jun 9, 95(12), 6647 - 52 Structural homologies with ATP- and folate-binding enzymes in the crystal structure of folylpolyglutamate synthetase; Sun X et al.; Folylpolyglutamate synthetase, which is responsible for the addition of a polyglutamate tail to folate and folate derivatives, is an ATP-dependent enzyme isolated from eukaryotic and bacterial sources, where it plays a key role in the retention of the intracellular folate pool . Here, we report the 2.4-A resolution crystal structure of the MgATP complex of the enzyme from Lactobacillus casei . The structural analysis reveals that folylpolyglutamate synthetase is a modular protein consisting of two domains, one with a typical mononucleotide-binding fold and the other strikingly similar to the folate-binding enzyme dihydrofolate reductase . We have located the active site of the enzyme in a large interdomain cleft adjacent to an ATP-binding P-loop motif . Opposite this site, in the C domain, a cavity likely to be the folate binding site has been identified, and inspection of this cavity and the surrounding protein structure suggests that the glutamate tail of the substrate may project into the active site . A further feature of the structure is a well defined Omega loop, which contributes both to the active site and to interdomain interactions . The determination of the structure of this enzyme represents the first step toward the elucidation of the molecular mechanism of polyglutamylation of folates and antifolates. J Dairy Sci, 1998 May, 81(5), 1353 - 7 Increase in milk yield of commercial dairy herds fed a microbial and enzyme supplement; McGilliard ML et al.; A microbial and enzyme supplement fed at 21.2 g/d per cow to 46 Virginia dairy herds increased the milk yield of 31 herds (17 significantly) and decreased the milk yield of 15 herds (7 significantly) . Effects of season were important but consistent with overall results . Herds began receiving the supplement, which contained dried fermentation products of Aspergillus oryzae, Bacillus subtilis, Lactobacillus acidophilus, and yeast culture, midway between the first and second monthly Dairy Herd Improvement tests and continued on the supplement through the 3rd mo . Entry of herds was staggered over 8 mo to reduce the influence of season . The trial involved 3417 cows with 5 test mo between 60 and 365 d in milk . Milk yield during mo 3 averaged 0.64 kg/d per cow more (+0.73 kg/d for first lactation cows and +0.56 kg/d for later lactation cows) than the mean milk yield during mo 1 and 5 . Herds completing the study before summer responded similarly to all other herds, which included herds that were fed the product during summer and those that finished the study during summer . Fat and protein yields and protein percentage differed little with or without the supplement . Fat percentage decreased (0.10%) . Twenty-one herds that were fed a yeast product prior to and during the study responded similarly to the 17 herds that were not fed a yeast product. J Clin Microbiol, 1998 Jun, 36(6), 1781 - 3 Peritonitis associated with vancomycin-resistant Lactobacillus rhamnosus in a continuous ambulatory peritoneal dialysis patient: organism identification, antibiotic therapy, and case report; Klein G et al.; A case of Lactobacillus rhamnosus-associated peritonitis in a patient undergoing continuous ambulatory peritoneal dialysis is reported . The patient was treated with vancomycin after isolation of glycopeptide-susceptible coagulase-negative staphylococci . After a skin rash developed, vancomycin was discontinued and replaced with teicoplanin . Seven weeks after the glycopeptide therapy was discontinued, a Lactobacillus strain was isolated in pure cultures . The isolate was identified first incorrectly as L . acidophilus but later correctly as L . rhamnosus . Antibiotic susceptibility testing showed that the isolate was resistant to glycopeptides but susceptible to several other antibiotics . The antibiotic treatment was then switched to imipenem and was successful. Int J Food Microbiol, 1998 Apr 14, 40(3), 169 - 75 Phosphate group requirement for mitogenic activation of lymphocytes by an extracellular phosphopolysaccharide from Lactobacillus delbrueckii ssp . bulgaricus; Kitazawa H et al.; The mitogenic activity of extracellular polysaccharides produced by Lactobacillus delbrueckii ssp . bulgaricus OLL 1073R-1 and NCFB2483 was examined in murine lymphocytes . The extracellular polysaccharide from Lactobacillus delbrueckii ssp . bulgaricus OLL 1073R-1 was fractionated into neutral and acidic polysaccharides by anion-exchange chromatography, while that of Lactobacillus delbrueckii ssp . bulgaricus NCFB2483 were all fractionated into neutral polysaccharide(s) . The acidic polysaccharide stimulated mitogenic responses of murine splenocytes and Peyer's patches but not of thymocytes . The optimal concentration of the acidic polysaccharide at the highest stimulation was 160 microg/ml . A significant increase of mitogenic activity was initiated at 24 h, and the highest response was obtained after stimulation for 48 h . The acidic polysaccharide purified by high performance liquid chromatography also had substantial mitogenic activity, and the molecular weight was estimated to be 1.2 x 10(6) . The acidic polysaccharide was a phosphopolysaccharide consisting of glucose, galactose and phosphorus . Dephosphorylation by hydrofluoric acid degradation reduced the mitogenic activity in lymphocytes . The phosphopolysaccharide produced by Lactobacillus delbrueckii ssp . bulgaricus 1073R-1 is a potent B-cell-dependent mitogen in which the phosphate group acts as a trigger of the mitogenic induction. Biochemistry, 1998 May 12, 37(19), 6883 - 93 Synthetic interface peptides as inactivators of multimeric enzymes: inhibitory and conformational properties of three fragments from Lactobacillus casei thymidylate synthase; Prasanna V et al.; Three synthetic peptides corresponding to distinct segments of the subunit interface of the dimeric enzyme thymidylate synthase (residues 17-38, N 22; residues 174-190, M 17; and residues 201-220, C 20) have been investigated for their ability to function as inhibitors by modifying the quaternary structure of the enzyme . A dramatic reduction of enzyme activity is observed following incubation of TS with the C 20 peptide . The N 22 and M 17 peptides were unable to cause any loss of enzymatic activity . Addition of the C 20 peptide results in a loss of fluorescence of TS labeled with a dansyl group at Cys 198, following aggregation and precipitation of the protein . The effects are not observed for the N 22 or M 17 peptides . Loss of enzymatic activity is related to the ability of C 20 to promote protein aggregation . The conformations of the peptides have been studied using CD and NMR in order to correlate the observed function with solution structures . Peptides N 22 and M 17 are largely unstructured in aqueous solution . A population of nascent helical structures or multiple turn conformations has been detected for the C 20 peptide in aqueous solution by NMR . Addition of 50% (v/v) hexafluoroacetone trihydrate (HFA), a structure-stabilizing cosolvent, stabilizes the helical conformation in the C 20 peptide . Under similar conditions, N 22 and M 17 remain largely extended with observations of local beta-turn conformations . Interestingly, the C 20 peptide is a beta-hairpin in the native structure, whereas the other two peptides are individual strand components of a beta-sheet. Protein Eng, 1998 Mar, 11(3), 171 - 83 The separate effects of E60Q in Lactobacillus casei thymidylate synthase delineate between mechanisms for formation of intermediates in catalysis; Birdsall DL et al.; X-Ray crystal structures of Lactobacillus casei thymidylate synthase (TS) mutant complexes of E60D with dUMP, and E60Q with dUMP or FdUMP, as well as ternary complexes with folate analog inhibitor CB3717, are described . The structures we report address the decrease in rate of formation of ternary complexes in the E60 mutants . Structures of ternary complexes of L.casei TS mimic ligand-bound TS just prior to covalent bond formation between ligands and protein . Ternary complex structures of L.casei TS E60Q show the ligands are not optimally aligned for making the necessary covalent bonds . Since CB3717 is an analog of the open, activated form of the cofactor, these structures suggest that the slow rate of ternary complex formation in E60 mutants is at least partly the result of impaired alignment of ligands in the active site after binding and activation of the cofactor . Binary complexes of TS E60Q and TS E60D with substrate (dUMP) show no change in dUMP position or occupancy . These results are consistent with the fact that Kd(dUMP) and Km(dUMP) are almost the same, and the rates of folate-independent debromination of 5-bromo-dUMP are even higher than for wild type TS. S D J Med, 1998 May, 51(5), 153 - 6 A case of Lactobacillus acidophilus endocarditis successfully treated with cefazolin and gentamicin; Vogt HB et al.; Infective endocarditis secondary to Lactobacillus acidophilus is rare and difficult to treat . Management of patients allergic to penicillin is further complicated by resistance of Lactobacillus organisms to commonly substituted antibiotics . We report a case of a 46-year old woman successfully treated with a prolonged course of cefazolin and gentamicin. Aust Dent J, 1998 Apr, 43(2), 110 - 6 Enamel cracks . The role of enamel lamellae in caries initiation; Walker BN et al.; Lamellae or cracks are distributed throughout tooth enamel in both deciduous and permanent dentitions . While earlier authors postulated that lamellae may be pathways of entry for caries, no evidence was adduced and the theory appears to have been discounted . The present study seeks to show that, at least in some cases, lamellae are permeable to dyes, may be associated with caries initiated in the dentine, supporting the hypothesis of Hardwick and Manly of lamellae penetration by Streptococcus mutans and lactobacilli . The enamel lamellae are shown to be a permeable pathway allowing caries-producing bacteria access to the dentine-enamel junction . Caries can thus be established within the tooth without visible evidence at the surface. Stomatologiia (Mosk), 1994 Apr-Jun, 73(2), 17 - 20 {The use of the new bacterial biopreparation Acilact in the combined treatment of periodontitis}; Pozharitskaia MM et al.; Acilact, a bacterial biopreparation representing a complex of live lyophilized acidophilic lactobacteria, was used in combined therapy of 45 patients with periodontitis of mild and medium severity . The drag was applied locally and per os . Clinical parameters improved after therapy; gram-positive cocci and bacilli predominated in local microflora; natural antibacterial resistance of the body improved . This method of therapy is new in principle and pathogenetically grounded . It results in correction of autoflora of the oral cavity and periodontal pouches, and, possibly, of the gastrointestinal tract . Acilact is well tolerated by the patients and induces no side effects, there are no contraindications against its administration. Gene, 1998 Jun 8, 212(2), 203 - 11 The arbZ gene from Lactobacillus delbrueckii subsp . lactis confers to Escherichia coli the ability to utilize the beta-glucoside arbutin; Weber BA et al.; From a genomic library of the industrially used strain Lactobacillus delbrueckii subsp . lactis DSM7290, a gene designated arbZ (869bp; encoding a 33.5kDa protein) was isolated by screening E . coli transformants for the ability to utilize the beta-glucoside arbutin . Out of 9000 transformants nine were able to ferment arbutin, whereas no utilization of the beta-glucosides salicin, esculin or cellobiose could be detected . Overexpression of arbZ using the T7-polymerase-T7-promoter-system resulted in the formation of insoluble, catalytically inactive protein aggregates (inclusion bodies) . Accordingly, overexpression was not accompanied by an increase in ArbZ activity . Induction of arbZ controlled by the lac promoter under conditions that reduce protein aggregation resulted in a 12-fold increase in arbutin hydrolyzing activity of intact cells and a 13-fold increase in phospho-beta-glycosidase activity in cell-free extracts of the respective transformants . Nucleotide sequence analysis revealed a second gene upstream of arbZ that was designated arbX (830bp) . ArbX (32.6kDa) shared similarity with several glycosyltransferases involved in the biosynthesis of lipopolysaccharides in Gram-negative bacteria . In Lb . delbrueckii subsp . lactis DSM7290 two transcripts, one covering arbX together with arbZ and one covering arbZ alone were detected by Northern blot analysis. J Oral Rehabil, 1998 Apr, 25(4), 304 - 10 The effect of prosthesis disinfection on salivary microbial levels; Mahonen K et al.; The aim of this study was to evaluate how the soaking of dentures in a disinfection solution affects salivary microbe counts and stomatitis of partially dentate patients . Patients soaked their dentures for 4 weeks randomly both in a disinfection solution and in a placebo solution . Mutans streptococci, lactobacilli and yeast counts were measured before and after each test period and also the flow rate, buffer capacity and pH of saliva were registered . Disinfection decreased all microbe levels investigated, but only lactobacilli counts decreased significantly . Placebo treatment had either no effect on salivary microbe counts or they increased slightly . Disinfection caused some reduction of the mucosal inflammation under the denture base, but could not completely remove stomatitis during the 4-week test period. Gerodontology, 1997 Jul, 14(1), 17 - 27 Oral glucose clearance in nonagenarians in relation to functional capacity, medication and oral variables; Lundgren M et al.; OBJECTIVES: To study oral sugar (glucose) clearance and to examine some factors which were believed to either influence or be dependent upon oral glucose clearance . DESIGN: Cross-sectional, clinical study with analysis of records . SETTING: Goteborg gerontological and geriatric population studies, Goteborg University, Sweden . SUBJECTS: 71 community-dwelling individuals, 27 men and 44 women, of a representative sample of 260 92-year-old persons . INTERVENTION AND MAIN OUTCOME MEASURES: Glucose concentration was measured in saliva after chewing of a glucose tablet and the clearance was assessed by three different variables: (i) the initial salivary glucose concentration, (ii) the area under the curve (AUC) and (iii) the clearance time . RESULTS: The glucose clearance showed a wide inter-individual variation, which could be explained partly by differences in oral state, chewing time, stimulated salivary secretion rate and medication use . A positive correlation was found between the clearance variables and the number of lactobacilli and mutans streptococci in saliva and the percentage of untreated root caries lesions of the total number of exposed root surfaces . CONCLUSIONS: A slow oral sugar clearance is more common among 92-year-olds than younger adults earlier reported in other studies, particularly in those who have uncompensated functional impairments and a high medication history . A decreased oral glucose clearance was associated with high counts of salivary lactobacilli and mutans streptococci and a high proportion of untreated root caries lesions. Appl Environ Microbiol, 1998 Jun, 64(6), 2313 - 4 Myoglobin as an inhibitor of exopeptidases from lactobacillus sake Sanz Y, Toldra F. The effects of myoglobin on exopeptidases of Lactobacillus sake were determined . Inhibition of the aminopeptidases increased as the myoglobin concentration increased; aminopeptidase 3 was the most affected (90% inhibition) . Aminopeptidases 1, 2, and 4 showed similar inhibition levels (around 60%) . Myoglobin did not affect tripeptidase activity . Thus, myoglobin could limit amino acid generation in meat systems. Am J Obstet Gynecol, 1998 May, 178(5), S245 - 9 Urogenital aging--a hidden problem; Samsioe G; Urogenital problems in the elderly female population are experienced by one third of women from the age 50 years and onward . Symptoms from the lower urinary tract include incontinence, urethritis, and recurrent urinary tract infections . Atrophic changes within the bladder neck and urethra could be corrected by estrogen administration even at doses so low that endometrial proliferation is avoided . Hence such estrogens could be given without progestogen comedication . Control of micturition is a complex process of which estrogen deficiency is only one of several factors . The aging process with subsequent changes in membrane permeability, neuromuscular function, and collagen synthesis contributes to the local problems of control of micturition . In addition, the central control may also be affected by degenerative changes of the nervous system . Vaginal symptoms comprise dryness of vagina, dyspareunia, and recurrent vaginitis often followed by a foul odor and discharge . The microflora with lactobacilli and low pH as seen in fertile women is gradually replaced by a mixed germ flora including several of the pathogenic organisms common in urinary tract infections . Vaginal pH increases from around 4 to between 6 and 7 . It is a puzzling fact that the urogenital tissues seem to be more "sensitive" to estrogens than other tissues . Conformational changes of the estrogen receptor(s) brought about by the local cytokine milieu is one possibility to explain the situation . The systemic absorption of low-dose estrogen preparations is dependent on the status of the vaginal mucosa . Absorption is high when the vaginal mucosa is atrophic and gradually decreases (but not to zero) as the vaginal mucosa matures under estrogen influence. Appl Environ Microbiol, 1998 Jun, 64(6), 2269 - 72 Antagonistic activity of Lactobacillus plantarum C11: two new two-peptide bacteriocins, plantaricins EF and JK, and the induction factor plantaricin A; Anderssen EL et al.; Six bacteriocinlike peptides (plantaricin A {PlnA}, PlnE, PlnF, PlnJ, PlnK, and PlnN) produced by Lactobacillus plantarum C11 were detected by amino acid sequencing and mass spectrometry . Since purification to homogeneity was problematic, all six peptides were obtained by solid-phase peptide synthesis and were tested for bacteriocin activity . It was found that L . plantarum C11 produces two two-peptide bacteriocins (PlnEF and PlnJK); a strain-specific antagonistic activity was detected at nanomolar concentrations when PlnE and PlnF were combined and when PlnJ and PlnK were combined . Complementary peptides were at least 10(3) times more active when they were combined than when they were present individually, and optimal activity was obtained when the complementary peptides were present in approximately equal amounts . The interaction between complementary peptides was specific, since neither PlnE nor PlnF could complement PlnJ or PlnK, and none of these peptides could complement the peptides constituting the two-peptide bacteriocin lactococcin G . Interestingly, PlnA, which acts as an extracellular signal (pheromone) that triggers bacteriocin production, also possessed a strain-specific antagonistic activity . No bacteriocin activity could be detected for PlnN. Appl Environ Microbiol, 1998 Jun, 64(6), 2192 - 9 Development of a probiotic cheddar cheese containing human-derived Lactobacillus paracasei strains; Gardiner G et al.; Cheddar cheese was manufactured with either Lactobacillus salivarius NFBC 310, NFBC 321, or NFBC 348 or L . paracasei NFBC 338 or NFBC 364 as the dairy starter adjunct . These five strains had previously been isolated from the human small intestine and have been characterized extensively with respect to their probiotic potential . Enumeration of these strains in mature Cheddar cheese, however, was complicated by the presence of high numbers (>10(7) CFU/g of cheese) of nonstarter lactic acid bacteria, principally composed of lactobacilli which proliferate as the cheese ripens . Attempts to differentiate the adjunct lactobacilli from the nonstarter lactobacilli based on bile tolerance and growth temperature were unsuccessful . In contrast, the randomly amplified polymorphic DNA method allowed the generation of discrete DNA fingerprints for each strain which were clearly distinguishable from those generated from the natural flora of the cheeses . Using this approach, it was found that both L . paracasei strains grew and sustained high viability in cheese during ripening, while each of the L . salivarius species declined over the ripening period . These data demonstrate that Cheddar cheese can be an effective vehicle for delivery of some probiotic organisms to the consumer. Appl Environ Microbiol, 1998 Jun, 64(6), 2013 - 9 The gal genes for the Leloir pathway of Lactobacillus casei 64H; Bettenbrock K et al.; The gal genes from the chromosome of Lactobacillus casei 64H were cloned by complementation of the galK2 mutation of Escherichia coli HB101 . The pUC19 derivative pKBL1 in one complementation-positive clone contained a 5.8-kb DNA HindIII fragment . Detailed studies with other E . coli K-12 strains indicated that plasmid pKBL1 contains the genes coding for a galactokinase (GalK), a galactose 1-phosphate-uridyltransferase (GalT), and a UDP-galactose 4-epimerase (GalE) . In vitro assays demonstrated that the three enzymatic activities are expressed from pKBL1 . Sequence analysis revealed that pKBL1 contained two additional genes, one coding for a repressor protein of the LacI-GalR-family and the other coding for an aldose 1-epimerase (mutarotase) . The gene order of the L . casei gal operon is galKETRM . Because parts of the gene for the mutarotase as well as the promoter region upstream of galK were not cloned on pKBL1, the regions flanking the HindIII fragment of pKBL1 were amplified by inverse PCR . Northern blot analysis showed that the gal genes constitute an operon that is transcribed from two promoters . The galKp promoter is inducible by galactose in the medium, while galEp constitutes a semiconstitutive promoter located in galK. Microbiol Res, 1998 Apr, 153(1), 29 - 35 Release of spirosin associated with potassium phosphate-induced autolysis in Lactobacillus reuteri DSM 20016; Yamato M et al.; We have studied the effect of medium components on spirosin production in Lactobacillus reuteri DSM 20016 to get some insight into the function of spirosome in Lactobacillus . Among those investigated, only potassium phosphate was found to influence the production of spirosin . Though it was not effective at concentrations lower than 0.6%, it promoted the spirosin production and its accumulation into culture medium in particular, at higher concentrations . The accumulation has been demonstrated to originate inthe release of spirosin due to the bacterial autolysis induced by the higher concentrations of potassium phosphate, The autolytic effect of potassium phosphate was assumed to be a concerted action by phosphate and potassium ions at the concentrations higher than 0.1 and 0.4 M, respectively . A possible role of spirosin as a sensor protein of bacterial two-component regulatory system was discussed. Arch Oral Biol, 1998 Feb, 43(2), 151 - 6 Stimulated salivary flow rate and composition in asthmatic and non-asthmatic adults; Lenander-Lumikari M et al.; The number of decayed, missed and filled permanent teeth (DMFT), the degree of periodontal inflammation (Periodontal Status Index, PSI), stimulated salivary flow rate and the concentrations of total protein, lactoferrin, lysozyme, myeloperoxidase, salivary peroxidase, calcium, potassium, sodium and thiocyanate in whole saliva of 26 adult asthma patients were compared with those of 33 non-asthmatic controls . The saliva was also analysed for mutans streptococci, lactobacilli, total anaerobic flora and Candida spp . The mean PSI (p < 0.05; 95% confidence interval for the difference between means (95% CI) 2.47-25.30) was higher and the mean stimulated salivary flow rate (p < or = 0.05; 95% CI 0.57-0.55) was lower in the asthmatic group than in the control group . No differences were found between the groups in non-immune defense factors, except for myeloperoxidase . The myeloperoxidase concentrations were higher in asthmatics than in non-asthmatics (p < 0.05; 95% CI 4.4-134.0 ng/ml) . No differences in microbial counts were found . It was concluded that stimulated salivary flow rates decrease while myeloperoxidase concentrations increase in adult asthmatic patients compared with non-asthmatic adults . The higher concentrations of myeloperoxidase are explained by a higher PSI in asthmatics. Arch Oral Biol, 1998 Feb, 43(2), 103 - 10 Binding properties of streptococcal glucosyltransferases for hydroxyapatite, saliva-coated hydroxyapatite, and bacterial surfaces; Vacca-Smith AM et al.; The binding specificities of Streptococcus glucosyltransferase (Gtf) B, C and D for hydroxyapatite (HA), saliva-coated hydroxyapatite (SHA), and bacterial surfaces were examined . For HA beads the following values were obtained: (K = affinity; N = number of binding sites) GtfB, K = 46 x 10(5) ml/mumol, N = 0.65 x 10(-6) mumol/m2; GtfC, K = 86 x 10(5) ml/mumol, N = 4.42 x 10(-6) mumol/m2.; GtfD, K = 100 x 10(5) ml/mumol, N = 0.83 x 10(-6) mumol/m2 . For SHA beads, the following values were obtained: GtfB, K = 14.7 x 10(5) ml/mumol, N = 1.03 x 10(-6) mumol/m2; GtfC, K = 21.3 x 10(5) ml/mumol, N = 3.66 x 10(-6) mumol/m2; GtfD, K = 1.73 x 10(5) ml/mumol, N = 8.88 x 10(-6) mumol/m2 . The binding of GtfB to SHA beads was reduced in the presence of parotid saliva, but the binding of GtfC and D was unaffected . The binding of GtfB to SHA in the presence of parotid saliva supplemented with GtfC and D was reduced when compared with its binding to SHA in the presence of parotid saliva alone . In contrast, te binding of GtfC and SHA was unaffected when parotid saliva was supplemented with the other Gtf enzymes . GtfB bound to several bacterial strains (Strep, mutans GS-5, Actinomyces viscosus OMZ105E and Lactobacillus casei 4646) in an active form, while GtfC and D did not bind to bacterial surfaces . It is concluded that of the three Gtf enzymes, GtfC has the highest affinity for HA and SHA surfaces and can adsorb on the the SHA surface in the presence of the other two enzymes . GtfD also binds to SHA in the presence of the other enzymes but has a very low affinity for the surface . GtfB does not bind to SHA in the presence of the other Gtf enzymes but binds avidly to bacterial surfaces in an active form . Therefore, GtfC most probably binds to apatitic surfaces, while GtfB binds to bacterial surfaces. Int J Paediatr Dent, 1995 Sep, 5(3), 149 - 55 Dental caries and prolonged breast-feeding in 18-month-old Swedish children; Hallonsten AL et al.; Three thousand children aged 18 months were screened for dental caries and ongoing breast-feeding at 46 child welfare centres in different parts of Sweden . Of these, 200 children were selected for a more comprehensive examination, involving investigation of dietary, toothbrushing and sucking habits, use of fluoride, and determination of salivary levels of mutans streptococci and lactobacilli . The children were divided into four groups: group 1: children with caries not being breast-fed; group 2: children with caries being breast-fed; group 3: caries-free children being breast-fed; group 4: caries-free gender- and age-matched reference children not being breast-fed . The results showed that 63 of the children (2.1%) had caries and 61 (2.0%) were still being breast-fed . Twelve (19.7%) of the 61 children still being breast-fed had caries compared with 51 (1.7%) of the 2939 children not being breast-fed; the difference was statistically significant . Children with caries and still being breast-fed had a mean defs of 5.3, and those with caries not being breast-fed 4.9; the difference was not statistically significant . Children with caries, irrespective of whether they were being breast-fed or not, had significantly higher numbers of cariogenic food intakes per day than caries-free children . Mutans streptococci were detected in 67% of the children and lactobacilli in 13% . Children with detectable mutans streptococci and lactobacilli had significantly more caries than those without . The results indicate that Swedish children with prolonged breast-feeding have a tendency to establish unsuitable dietary habits which constitutes a risk situation for developing caries at an early age. J Biol Chem, 1998 May 22, 273(21), 12929 - 34 Activation of thiamin diphosphate and FAD in the phosphatedependent pyruvate oxidase from Lactobacillus plantarum; Tittmann K et al.; The phosphate- and oxygen-dependent pyruvate oxidase from Lactobacillus plantarum is a homotetrameric enzyme that binds 1 FAD and 1 thiamine diphosphate per subunit . A kinetic analysis of the partial reactions in the overall oxidative conversion of pyruvate to acetyl phosphate and CO2 shows an indirect activation of the thiamine diphosphate by FAD that is mediated by the protein moiety . The rate constant of the initial step, the deprotonation of C2-H of thiamine diphosphate, increases 10-fold in the binary apoenzyme-thiamine diphosphate complex to 10(-2) s-1 . Acceleration of this step beyond the observed overall catalytic rate constant to 20 s-1 requires enzyme-bound FAD . FAD appears to bind in a two-step mechanism . The primarily bound form allows formation of hydroxyethylthiamine diphosphate but not the transfer of electrons from this intermediate to O2 . This intermediate form can be mimicked using 5-deaza-FAD, which is inactive toward O2 but active in an assay using 2,6-dichlorophenolindophenol as electron acceptor . This analogue also promotes the rate constant of C2-H dissociation of thiamine diphosphate in pyruvate oxidase beyond the overall enzyme turnover . Formation of the catalytically competent FAD-thiamine-pyruvate oxidase ternary complex requires a second step, which was detected at low temperature. Int J Food Microbiol, 1998 Mar 3, 40(1-2), 87 - 92 Development of a growth medium suitable for exopolysaccharide production by Lactobacillus delbrueckii ssp . bulgaricus RR; Kimmel SA et al.; Complex media are commonly used in studies examining exopolysaccharide production by Lactobacillus delbrueckii ssp . bulgaricus . However, quantification of exopolysaccharide in complex medium can be complicated by interference due to carbohydrate polymers contained in media components . This study was undertaken to identify components of MRS, a common medium for cultivation of L . delbrueckii ssp . bulgaricus, that interfere with exopolysaccharide quantification, to develop a medium for production of exopolysaccharide that provides for growth of L . delbrueckii ssp . bulgaricus strain RR similar to MRS, and to demonstrate exopolysaccharide production by L . delbrueckii ssp . bulgaricus RR grown in the newly developed medium . Phenol-sulfuric acid determinations were conducted on uninoculated MRS broth with and without yeast extract, beef extract and proteose peptone #3 . These three ingredients accounted for 94% of the total background exopolysaccharide-equivalent in MRS broth . Based on these results, a semi-defined medium (SDM) providing minimal interference was developed using yeast nitrogen base and Bacto casitone . Growth of L . delbrueckii ssp . bulgaricus RR at 42 degrees C in semi-defined medium and MRS was evaluated, and generation times did not differ significantly (0.94 h in MRS and 0.85 h in SDM) . Exopolysaccharide production by L . delbrueckii ssp . bulgaricus RR during growth in semi-defined medium was evaluated at 30 and 40 degrees C . The rate of exopolysaccharide production was lower at 30 degrees C (8.04 (mg/l-h) than at 40 degrees C (11.95 (mg/l-h), but the maximal concentration of exopolysaccharide produced was similar at both temperatures. Int J Food Microbiol, 1998 Mar 3, 40(1-2), 43 - 9 Improvement of garri quality by the inoculation of microorganisms into cassava mash; Okafor N et al.; Lactobacillus delbruckii, Lactobacillus coryneformis, and a Saccharomyces sp., previously found among 214 isolates to be the highest producers of linamarase, amylase, and lysine were inoculated separately or mixed into cassava mash and fermented with, or without dewatering, for 24, 48, 72, 96 and 120 h . At the end of the fermentation period, the mash was converted to garri by heating over a gas burner . The mash and the garri resulting from it were assessed for lysine and residual cyanide, while the garri was also studied for its organoleptic properties . The inoculation of the microorganisms into cassava mash produced a sharp drop in the cyanide content of the mash, particularly when the mixture of organisms was inoculated into undewatered cassava mash rather the single organisms . After 24 h, while the cyanide content of the control (uninoculated mash) mash was 3.06 microg/g in the dewatered mash, and 4.24 microg/g in the undewatered mash, the inoculation of a mixture of the three organisms caused the cyanide content in the inoculated mashes to drop by 150% to 1.96 microg/g (dewatered mash) and by 300% to 1.43 microg/g (undewatered mash) . It also appears that the process of producing the garri from the mash by heating, caused a further reduction of the cyanide content: thus the garri always contained less cyanide than the mash from which it was made . The lysine content of the mash was also highest when all three organisms were mixed; it also tended to increase with increasing length of fermentation of the mash . Whereas the single organism most effective in reducing the cyanide content of mash was Lactobacillus delbruckii, in the case of lysine production, it was the yeast . The organoleptic properties of the garri which were assessed were flavour, texture, colour and general acceptability . In general these properties were superior at the P < 0.01 level in garri made from the undewatered mash in comparison with that from dewatered mash, especially when the mixture of organisms was used . The inoculation of the mixture of the three organisms produced a dramatic reduction in the time (24 h) taken for the highest 'general acceptability' score to be given by the tasters when compared with the singly inoculated organisms and the control, which attained this characteristic after about 96 h of incubation in mash. Int J Food Microbiol, 1998 Mar 3, 40(1-2), 17 - 25 Plantaricin LP84, a broad spectrum heat-stable bacteriocin of Lactobacillus plantarum NCIM 2084 produced in a simple glucose broth medium; Suma K et al.; Lactobacillus plantarum NCIM 2084 produced an antibacterial substance when grown at 40 degrees C for 36 h in a laboratory medium . The antibacterial substance was active against a wide range of bacteria comprising Gram positive and negative foodborne pathogenic and spoilage bacteria . However, related mesophilic lactobacilli were not inhibited, except for L . amylovorus DSM 20531 . The antimicrobial activity was observed between late log and stationary growth phases . The antibacterial substance was partially purified through concentration under vacuum, followed by extraction with methanol and acetone (M-A extract) . On fractionation of the M-A extract through Sephadex G-25, the activity was present in an eluant volume of 85 to 100 ml (peak I), indicating an apparent molecular mass of between 1 and 5 kDa and the purification attained was 80-fold . The antimicrobial principle was stable to heat (121 degrees C for 20 min) and catalase, but sensitive to trypsin and chymotrypsin, indicating it to be a bacteriocin . The M-A extract exhibited a bactericidal and lytic effect against Bacillus cereus F 4810 and Escherichia coli D 21 . The ability of L . plantarum NCIM 2084 to produce an effective bacteriocin in a simple growth medium is of potential interest in its application as a biopreservative in traditional fermented foods. Gene, 1998 Mar 27, 210(1), 61 - 70 Structure of a genome region of the Lactobacillus gasseri temperate phage phiadh covering a repressor gene and cognate promoters; Engel G et al.; By sequencing the DNA regions which flank the intG gene encoding integrase of the temperate Lactobacillus (Lb.) gasseri bacteriophage phiadh, a continuous sequence of 6590 bp was established . It encompasses five newly identified ORFs, of which four are located upstream, and one (orfC) downstream of intG . Proteins corresponding to the expected products of the intG upstream coding regions, orfA (33 kDa), orf2 (14 kDa), rad (12.1 kDa), and tec (7.9 kDa), were identified by in vitro expression of subcloned DNA fragments . Rad shares homology with transcription regulators, including SinR of Bacillus species and the repressor of phage phi105 . The gporf2 is similar to predicted products of topologically equivalent coding regions of the Lactococcus lactis phage TP901-1 and the B . subtilis phage phi105 . Promoters for the divergently oriented rad and tec genes were mapped within the 435-bp region between them and specify overlapping transcripts with extended 5'-untranslated sequences . As shown with lacZ fusions, Rad repressed transcription from the tec and rad promoters 20- and 5-fold, respectively . In Lb . gasseri, weak expression of cloned rad ws sufficient to mediate immunity towards phiadh. J Dent, 1998 Mar, 26(3), 267 - 71 Antibacterial activity of dentine primer containing MDPB after curing; Imazato S et al.; OBJECTIVES: A monomer methacryloyloxydodecylpyridinium bromide (MDPB) has antibacterial activity before polymerization . Furthermore, the antibacterial agent is immobilized by the polymerization of MDPB and the resin-based material incorporating MDPB is able to show an antibacterial effect even after being cured . The purpose of this study was to investigate the antibacterial effect of a dentine primer containing MDPB after curing . METHODS: The inhibitory effect of a cured MDPB-containing primer on the growth of Streptococcus mutans, Actinomyces viscosus and Lactobacillus casei was determined by the agar-disc method . The bactericidal activity of cured primer during a 1-h contact period was assessed using S . mutans, and the elution of unpolymerized MDPB was measured with high performance liquid chromatography . RESULTS: Cured MDPB-containing primer showed an inhibitory effect on the growth of all species which were in contact with the specimen surface, and displayed a little bactericidal effect on S . mutans without releasing any unpolymerized antibacterial components . CONCLUSION: Incorporation of antibacterial monomer MDPB into dentine primer is beneficial for providing antibacterial activity after curing. J Infect Dis, 1998 May, 177(5), 1386 - 90 Effect on normal vaginal flora of three intravaginal microbicidal agents potentially active against human immunodeficiency virus type 1; Rosenstein IJ et al.; The effect on normal vaginal flora of three intravaginal microbicides potentially active against human immunodeficiency virus type 1 was examined . Volunteers received dextrin sulfate (D2S), nonoxynol-9 (N-9), or docusate sodium in separate placebo-controlled studies . High vaginal swabs were obtained for bacterial culture before and after microbicide application . D2S did not affect the vaginal flora . However, lactobacilli decreased by > or = 10(2) cfu/mL in 9 (56%) of 16 women given N-9 and in 5 (63%) of 8 women given docusate sodium . Women using N-9 were also significantly more likely to become colonized abnormally (usually with aerobic gram-negative rods) than were those using placebo, as were women using docusate sodium . Women with reduced lactobacilli were less likely to regain normal flora than were those whose lactobacilli were unaffected . However, coliform colonization occurred whether lactobacilli produced H2O2 or not . Continuous use of N-9 could induce susceptibility to urinary and gynecological infection . It is essential that potential microbicides are examined for activity against normal vaginal flora. Ginekol Pol, 1998 Feb, 69(2), 82 - 6 {The presence of staphylococci in the vagina of pregnant women}; Krzeminski Z et al.; We were investigating the colonisation rate as well as the quantity of staphylococci in the vagina of women with physiological and complicated pregnancy . We have found high frequency of staphylococci (coagulase-negative and/or coagulase-positive) . Vaginal carriage rate amount 90% . According to our results neither the presence nor the quantity of these microorganisms were related to the presence or the number of lactobacilli, among them to the hydrogen peroxide producing ones . We have also assumed that neither colonisation nor the quantity of staphylococci have any influence on the course of pregnancy. J Dent Assoc S Afr, 1998 Jan, 53(1), 3 - 6 Lactobacillus species associated with active caries lesions; Botha SJ et al.; Lactobacilli that are most frequently associated with active caries lesions in dentine were isolated and identified as part of a research project which aims to determine the role of the predominant species of these organisms in the carious process . Samples of carious dentine were collected from 12 patients with open caries lesions (Group A) and stimulated saliva samples were collected from 12 patients with a DMFT = 0 and confirmed presence of lactobacilli in the oral cavity (Group B) . After serial dilutions samples were plated on Rogosa agar and incubated anaerobically at 37 degrees C for 48 hours . Representative colonies were isolated from each sample, using Harrison's disc and species were identified by classical taxonomy . A total of 153 isolates were identified . The redefinition and description of lactobacilli species in recent systematic literature resulted in a new and different species composition of oral lactobacilli as shown in this study, namely: homofermentative species (Group A = 82 per cent; Group B = 90 per cent) were predominantly Lactobacillus paracasei (Group A = 39 per cent; Group B = 30 percent) and Lactobacillus rhamnosus (Group A = 31 per cent; Group B = 41 per cent) . Heterofermentative species (Group A = 18 per cent; Group B = 10 per cent) were predominantly Lactobacillus fermentum (Group A = 68 per cent; Group B = 100 percent). Eur J Oral Sci, 1998 Apr, 106(2 Pt 1), 616 - 22 Intra-individual variations of salivary microbial levels in young adults; Petti S et al.; The variations of salivary levels of total viable flora, oral streptococci, Streptococcus mutans, Lactobacillus and Candida in twenty-three subjects, over a 6-month period, trying to control many potential sources of variability, were investigated . Most subjects showed log count variations of the microbial parameters larger than 1 . They were 95.6% (total flora), 91.2% (oral streptococci), 73.9% (lactobacilli), 60.8% (Strep . mutans) and 30.3% (Candida) . The intra-individual fluctuations were larger than the fluctuations of the means of the counts between samples . This suggests that the shifts in levels of these micro-organisms were more frequent intra-individually than at a population level . Strep . mutans levels significantly explained Streptococcus-Oral (inverse correlation), Lactobacillus and Candida variability . The reported variations were due to technical and biological factors and suggest that, in order to assess the salivary level of some microbial parameters in an individual, the mean count and the range of counts, obtained by more than two samples taken under the same conditions, should be considered. Spec Care Dentist, 1997 Mar-Apr, 17(2), 65 - 9 The level of cariogenic micro-organisms in patients with Sjögren's syndrome; Kolavic SA et al.; Sixteen patients with caries-inactive sjogren's syndrome with low parotid salivary flow rates (< 0.25 mL/min) and 18 caries-inactive control subjects with higher salivary flow rates were compared . Mutans streptococci (MS) and lactobacilli (LB) counts were measured by means of Dentocult SM strip mutans and LB assays . The group with Sjogren's syndrome displayed higher counts of MS (P = 0.014) and LB (p = 0.003) when compared with controls . The results of this study indicate that patients with caries-inactive Sjogren's syndrome and low salivary flow may have higher colonization of cariogenic micro-organisms than healthy individuals. Biochemistry, 1998 Apr 21, 37(16), 5528 - 35 Gemcitabine 5'-triphosphate is a stoichiometric mechanism-based inhibitor of Lactobacillus leichmannii ribonucleoside triphosphate reductase: evidence for thiyl radical-mediated nucleotide radical formation; Silva DJ et al.; Ribonucleoside triphosphate reductase (RTPR) from Lactobacillus leichmannii utilizes adenosylcobalamin and catalyzes the conversion of nucleoside triphosphates to deoxynucleoside triphosphates . One equivalent of 2',2'-difluoro-2'-deoxycytidine 5'-triphosphate, F2dCTP, rapidly inactivates RTPR . Analysis of the reaction products reveals that inactivation is accompanied by release of two fluoride ions and 0.84 equiv of 5'-deoxyadenosine and attachment of 1 equiv of corrin covalently to an active-site cysteine residue of RTPR . No cytosine release was detected . Proteolysis of corrin-labeled RTPR with endoproteinase Glu-C and peptide mapping at pH 5.8 revealed that C419 was predominantly modified . The kinetics of the inactivation have been examined by stopped-flow (SF) UV-vis spectroscopy and rapid freeze quench (RFQ) electron paramagnetic resonance (EPR) spectroscopy . Monitoring DeltaA525 nm shows that cob(II)alamin is formed with an apparent kobs of 50 s-1, only 2 . 5-fold slower than a similar experiment carried out with cytidine 5'-triphosphate (CTP) . The same reaction mixture was thus quenched at times from 22 ms to 30 s and examined by EPR spectroscopy . At early time points the EPR spectrum resembled a thiyl radical exchange coupled to cob(II)alamin . From 22 to 255 ms the total spin concentration remained unchanged at 1.4 spins/RTPR, twice that predicted by the amount of cob(II)alamin determined by SF . However, with time the signal attributed to the thiyl radical-cob(II)alamin disappears and new signal(s) with broad feature(s) at g = 2.33 and a sharp feature at g = 2.00 appeared, suggesting formation of cob(II)alamin and a nucleotide-based radical with only dipolar interactions . These studies have been interpreted to support the proposal that an RTPR-based thiyl radical can give rise to a nucleotide-based radical. Int J Food Microbiol, 1998 Feb 17, 39(3), 205 - 11 Lactic acid fermentation and storage of blanched garlic; de Castro A et al.; The controlled fermentation of peeled, blanched garlic, using a starter culture of Lactobacillus plantarum, was studied and compared with that of unblanched garlic . Blanching was carried out in hot water (90 degrees C) for 15 min . The starter grew abundantly in the case of blanched garlic, producing mainly lactic acid and reaching a pH of 3.8 after 7 days, but its growth was inhibited in unblanched garlic . Ethanol and fructose, coming from enzymatic activities of the garlic, and a green pigment were formed during the fermentation of unblanched garlic, but not of blanched garlic . The blanched garlic fermented by L . plantarum, even without a preservation treatment (pasteurization), was microbiologically stable during storage at 30 degrees C in an acidified brine (approximately 3% (w/w) NaCl and pH 3.5 at equilibrium), but fructans were hydrolyzed . The packed fermented product and that obtained by direct packing without fermentation were not significantly different with regard to flavour. J Bacteriol, 1998 Mar, 180(6), 1381 - 8 Characterization of IS1515, a functional insertion sequence in Streptococcus pneumoniae; Munoz R et al.; We describe the characterization of a new insertion sequence, IS1515, identified in the genome of Streptococcus pneumoniae I41R, an unencapsulated mutant isolated many years ago (R . Austrian, H . P . Bernheimer, E . E . B . Smith, and G . T . Mills, J . Exp . Med . 110:585-602, 1959) . A copy of this element located in the cap1EI41R gene was sequenced . The 871-bp-long IS1515 element possesses 12-bp perfect inverted repeats and generates a 3-bp target duplication upon insertion . The IS encodes a protein of 271 amino acid residues similar to the putative transposases of other insertion sequences, namely IS1381 from S . pneumoniae, ISL2 from Lactobacillus helveticus, IS702 from the cyanobacterium Calothrix sp . strain PCC 7601, and IS112 from Streptomyces albus G . IS1515 appears to be present in the genome of most type 1 pneumococci in a maximum of 13 copies, although it has also been found in the chromosome of pneumococcal isolates belonging to other serotypes . We have found that the unencapsulated phenotype of strain 141R is the result of both the presence of an IS1515 copy and a frameshift mutation in the cap1EI41R gene . Precise excision of the IS was observed in the type 1 encapsulated transformants isolated in experiments designed to repair the frameshift . These results reveal that IS1515 behaves quite differently from other previously described pneumococcal insertion sequences . Several copies of IS1515 were also able to excise and move to another locations in the chromosome of S . pneumoniae . To our knowledge, this is the first report of a functional IS in pneumococcus. Microbiology, 1998 Apr, 144 ( Pt 4), 905 - 14 An operon encoding three glycolytic enzymes in Lactobacillus delbrueckii subsp . bulgaricus: glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase and triosephosphate isomerase; Branny P et al.; The structural genes gap, pgk and tpi encoding three glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 3-phosphoglycerate kinase (PGK) and triosephosphate isomerase (TPI), respectively, have been cloned and sequenced from Lactobacillus delbrueckii subsp . bulgaricus (L . bulgaricus) . The genes were isolated after screening genomic sublibraries with specific gap and pgk probes obtained by PCR amplification of chromosomal DNA with degenerate primers corresponding to amino acid sequences highly conserved in GAPDHs and PGKs . Nucleotide sequencing revealed that the three genes were organized in the order gap-pgk-tpi . The translation start codons of the three genes were identified by alignment of the N-terminal sequences . These genes predicted polypeptide chains of 338, 403 and 252 amino acids for GAPDH, PGK and TPI, respectively, and they were separated by 96 bp between gap and pgk, and by only 18 bp between pgk and tpi . The codon usage in gap, pgk, tpi and three other glycolytic genes from L . bulgaricus differed, noticeably from that in other chromosomal genes . The site of transcriptional initiation was located by primer extension, and a probable promoter was identified for the gap-pgk-tpi operon . Northern hybridization of total RNA with specific probes showed two transcripts, an mRNA of 1.4 kb corresponding to the gap gene, and a less abundant mRNA of 3.4 kb corresponding to the gap-pgk-tpi cluster . The absence of a visible terminator in the 3'-end of the shorter transcript and the location of this 3'-end inside the pgk gene indicated that this shorter transcript was produced by degradation of the longer one, rather than by an early termination of transcription after the gap gene. Caries Res, 1998, 32(3), 166 - 74 Five-year incidence of caries, salivary and microbial conditions in 60-, 70- and 80-year-old Swedish individuals; Fure S; The 5-year incidence of dental caries in a random sample of 60-, 70- and 80-year-old inhabitants of Goteborg was related to salivary and microbial conditions . Of the 208 persons examined at baseline, 148 (71%) participated in the follow-up examination; 69, 51 and 28, respectively, in the different age groups . The study revealed that 27% of the participants had not developed any carious lesions during the 5-year period and that the incidence of coronal and root caries increased with age . In the 60-year-olds, 2.5% of the susceptible coronal and root surfaces, respectively, had decayed, while the corresponding figures for the 80-year-olds were 8.8% for coronal surfaces and 9.8% for root surfaces . In all, 18% had an unstimulated saliva secretion rate of below 0.1 ml/min and 14% had a stimulated secretion rate of <0.7 ml/min, with a mean rate which decreased with increasing age from 2.0 to 1.6 and 1.3 ml/min (p = 0.02) . The overall salivary counts of lactobacilli and mutans streptococci, particularly the subspecies of Streptococcus sobrinus, had increased during the period . In the respective age groups of 60, 70 and 80 years, 15, 39 and 39% had a mutans streptococci count of > or = 10(6) CFU/ml in saliva and the corresponding figures for > or = 10(5) lactobacilli counts were 22, 31 and 43% . In the stepwise regression analysis, it was found that age, salivary levels of mutans streptococci and lactobacilli and number of teeth were the best predictors of the incidence of root caries . In conclusion, these observations indicate that there is an increased risk of dental caries with age owing to unfavourable microbial and salivary conditions. J Bacteriol, 1998 May, 180(9), 2312 - 20 Cloning, sequence analysis, and characterization of the genes involved in isoprimeverose metabolism in Lactobacillus pentosus; Chaillou S et al.; Two genes, xylP and xylQ, from the xylose regulon of Lactobacillus pentosus were cloned and sequenced . Together with the repressor gene of the regulon, xylR, the xylPQ genes form an operon which is inducible by xylose and which is transcribed from a promoter located 145 bp upstream of xylP . A putative xylR binding site (xylO) and a cre-like element, mediating CcpA-dependent catabolite repression, were found in the promoter region . L . pentosus mutants in which both xylP and xylQ (LPE1) or only xylQ (LPE2) was inactivated retained the ability to ferment xylose but were impaired in their ability to ferment isoprimeverose (alpha-D-xylopyranosyl-(1,6)-D-glucopyranose) . Disruption of xylQ resulted specifically in the loss of a membrane-associated alpha-xylosidase activity when LPE1 or LPE2 cells were grown on xylose . In the membrane fraction of wild-type bacteria, alpha-xylosidase could catalyze the hydrolysis of isoprimeverose and p-nitrophenyl-alpha-D-xylopyranoside with apparent Km and Vmax values of 0.2 mM and 446 nmol/min/mg of protein, and 1.3 mM and 54 nmol/min/mg of protein, respectively . The enzyme could also hydrolyze the alpha-xylosidic linkage in xyloglucan oligosaccharides, but neither methyl-alpha-D-xylopyranoside nor alpha-glucosides were substrates . Glucose repressed the synthesis of alpha-xylosidase fivefold, and 80% of this repression was released in an L . pentosus delta ccpA mutant . The alpha-xylosidase gene was also expressed in the absence of xylose when xylR was disrupted. Infect Immun, 1998 May, 66(5), 1985 - 9 Adherence of human vaginal lactobacilli to vaginal epithelial cells and interaction with uropathogens; Boris S et al.; Three strains of Lactobacillus, identified as Lactobacillus acidophilus, Lactobacillus gasseri, and Lactobacillus jensenii, were selected from among 70 isolates from the vaginas of healthy premenopausal women for properties relevant to mucosal colonization or antagonism . All three self-aggregated and adhered to epithelial vaginal cells, displacing well-known vaginal pathogens, such as G . vaginalis, and inhibiting the growth in vitro of Escherichia coli and Streptococcus agalactiae . The surface components involved in self-aggregation appeared to be proteins for L . gasseri and lipoproteins for L . acidophilus and L . jensenii, as judged by susceptibility to treatment with appropriate degrading enzymes . The factors responsible for adherence to epithelial vaginal cells seemed to be glycoproteins (L . acidophilus and L . gasseri) and carbohydrate (L . jensenii) . The receptors of the vaginal cells were glycolipids, which presumably were the targets of the competition observed between the lactobacilli and the pathogenic microbes. Appl Environ Microbiol, 1998 May, 64(5), 1871 - 7 Molecular analysis of the locus responsible for production of plantaricin S, a two-peptide bacteriocin produced by Lactobacillus plantarum LPCO10; Stephens SK et al.; A 4.5-kb region of chromosomal DNA carrying the locus responsible for the production of plantaricin S, a two-peptide bacteriocin produced by Lactobacillus plantarum LPCO10 (R . Jimenez-Diaz, J . L . Ruiz-Barba, D . P . Cathcart, H . Holo, I . F . Nes, K . H . Sletten, and P . J . Warner, Appl . Environ . Microbiol . 61:4459-4463, 1995), has been cloned, and the nucleotide sequence has been elucidated . Two genes, designated plsA and plsB and encoding peptides alpha and beta, respectively, of plantaricin S, plus an open reading frame (ORF), ORF2, were found to be organized in an operon . Northern blot analysis showed that these genes are cotranscribed, giving a ca . 0.7-kb mRNA, whose transcription start point was determined by primer extension . Nucleotide sequences of plsA and plsB revealed that both genes are translated as bacteriocin precursors which include N-terminal leader sequences of the double-glycine type . The role of ORF2 is unknown at the moment, although it might be expected to encode an immunity protein of the type described for other bacteriocin operons . In addition, several other potential ORFs have been found, including some which may be responsible for the regulation of bacteriocin production . Two of them, ORF8 and ORF14, show strong homology with histidine protein kinase and response regulator genes, respectively, which have been found to be involved in the regulation of the production of other bacteriocins from lactic acid bacteria . A third ORF, ORF5, shows homology with gene agrB from Staphylococcus aureus, which is involved in the mechanism of regulation of the virulence phenotype in this species . Thus, an agr-like regulatory system for the production of plantaricin S is postulated. Appl Environ Microbiol, 1998 May, 64(5), 1831 - 6 Cloning and characterization of a prolinase gene (pepR) from Lactobacillus rhamnosus; Varmanen P et al.; A peptidase gene expressing L-proline-beta-naphthylamide-hydrolyzing activity was cloned from a gene library of Lactobacillus rhamnosus 1/6 isolated from cheese . Peptidase-expressing activity was localized in a 1.5-kb SacI fragment . A sequence analysis of the SacI fragment revealed the presence of one complete open reading frame (ORF1) that was 903 nucleotides long . The ORF1-encoded 34.2-kDa protein exhibited 68% identity with the PepR protein from Lactobacillus helveticus . Additional sequencing revealed the presence of another open reading frame (ORF2) following pepR; this open reading frame was 459 bp long . Northern (RNA) and primer extension analyses indicated that pepR is expressed both as a monocistronic transcriptional unit and as a dicistronic transcriptional unit with ORF2 . Gene replacement was used to construct a PepR-negative strain of L . rhamnosus . PepR was shown to be the primary enzyme capable of hydrolyzing Pro-Leu in L . rhamnosus . However, the PepR-negative mutant did not differ from the wild type in its ability to grow and produce acid in milk . The cloned pepR expressed activity against dipeptides with N-terminal proline residues . Also, Met-Ala, Leu-Leu, and Leu-Gly-Gly and the chromogenic substrates L-leucine-beta-naphthylamide and L-phenylalanine-beta-naphthylamide were hydrolyzed by the PepR of L . rhamnosus. Lett Appl Microbiol, 1998 Mar, 26(3), 231 - 5 Plantaricin D, a bacteriocin produced by Lactobacillus plantarum BFE 905 ready-to-eat salad; Franz CM et al.; Lactobacillus plantarum BFE 905 isolated from 'Waldorf' salad produced a bacteriocin termed plantaricin D which was active against Lact . sake and Listeria monocytogenes strains . Plantaricin D was heat stable, retaining activity after heating at 121 degrees C . The bacteriocin was inactivated by alpha-chymotrypsin, trypsin, pepsin and proteinase K, but not by papain and other