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| Eur J Biochem, 1975 Jun, 54(2), 505 - 14 Trans-N-deoxyribosylase: purification by affinity chromatography and characterization; Holguin J et al.; trans-N-Deoxyribosylase (EC 2.4.2.6) is usually considered as a single protein catalyzing indifferently the transfer of the deoxyribosyl moiety to and from a purine or a pyrimidine base . Affinity chromatography of an extract from Lactobacillus helveticus with two types of ligands allowed the separation and purification of two distinct trans-N-deoxyribosylases . One catalyzes specifically the deoxyribosyl transfer to and from purine bases exclusively: trans-N-deoxyribosylase-I, the other catalyzes the transfer to and from pyrimidine and purine bases: trans-N-deoxyribosylase-II . A Tris inhibition study showed a markedly different susceptibility of the two enzymes . Preliminary results indicate that the purine-specific enzyme is a polymeric enzyme of molecular weight 86 000 (+/- 4000). J Gen Microbiol, 1975 Jun, 88(2), 355 - 63 Glycerol teichoic acid as an antigenic determinant in a Gram-negative bacterium Butyrivibrio fibrisolvens; Sharpe ME et al.; An antigenic determinant isolated from a strain of the Gram-negative bacterium Butyrivibrio fibrisolvens reacted with specific antisera to the polyglycerophosphate backbone of membrane teichoic acids of lactobacilli . It gave a reaction of identity with membrane glycerol lipoteichoic acid and glycerol teichoic acid preparations from lactobacilli, and with phenol extracts of other Gram-positive bacteria . The antigen-antibody reactions was strongly inhibited by glycerol-phosphoryl-glycerol-phosphoryl-glycerol and the chemical composition was consistent with glycerol teichoic acid . It was concluded that this Gram-negative bacterium contained a glycerol teichoic acid whose polyglycerophospate backbone was acting as antigenic determinant . Extracts of 33 out of 52 other strains of butyrivibrios examined gave similar reactions. Prikl Biokhim Mikrobiol, 1975 May-Jun, 11(3), 476 - 7 {Volatile oil of Anethum Graveolens L . as an inhibitor of yeast and lactic acid bacteria}; Shcherbanovsky LR et al.; The antimicrobial activity of 25 volatile oils from aerial parts and seeds of dill (Anethum graveolens L.) of different geographical origin towards yeast Saccharomyces vini and lactic acid bacteria Lactobacterium buchneri was measured by serial dilutions . Volatile oils from mature seeds and green parts of the plants harvested at late vegetation phases showed the highest activity . The geographical origin of plants influenced insignificantly the antimicrobial activity of volatile oil. Infect Immun, 1975 May, 11(5), 973 - 81 Characterization of group N streptococcus lipoteichoic acid; Wicken AJ et al.; Lipoteichoic acid was extracted from the group N organism Streptococcus lactis ATCC 9936 with hot aqueous phenol and purified by gel chromatography followed by affinity chromatography using Ricinus communis lectin as the specific absorbent . The teichoic acid moiety of the lipoteichoic acid was calculated to contain 16 to 17 glycerol phosphate units, approximately half of which were substituted with alpha-D-galactosyl residues; the glycolipid moiety contained O-alpha-D-glucosyl-1 yields 2-O-alpha-D-glucosyl-1 yields 1-glycerol . The finding of 2-O-alpha-D-galactosyl glycerol in the lipid fraction of hydrofluoric acid hydrolysates suggests that fatty acids also occur as substituents on the main chain of the lipoteichoic acid . The reactivity of the lipoteichoic acid with R . communis lectin was studied by the quantitative precipitin method and compared with the reactivity of Lactobacillus fermenti lipoteichoic acid, which has a lower degree of alpha-D-galactosyl substitution . Group N antiserum reacted strongly with the S . lactis lipoteichoic acid and cross-reacted with L . fermenti lipoteichoic acid . From inhibition studies it is concluded that the antibodies are specific for alpha-D-galactosyl substituents . In addition to lipoteichoic acid, a fraction was obtained by gel chromatography which contained galactose and reacted with group N antiserum but could be distinguished from the lipoteichoic acid by immunoelectrophoresis. Pathol Biol (Paris), 1975 May, 23(5), 367 - 70 {Immunoglobulins A in the vagina . Assay and study of their specificity}; Thierry RC et al.; The authors have titrated, by the Laurell technique, immunoglobulin A in vaginal washings ; the quantity of IgA found is higher for women having a pathogenic vaginal flora . Using immunofluorescence technique, and peroxydase-marked antibodies, the authors found specific IgA directed against Lactobacillus, N . gonorrhoeae and Candida albicans. J Med Chem, 1975 May, 18(5), 526 - 8 Synthesis of a fluorescent derivative of amethopterin,; Gapski GR et al.; Fluorescein isothiocyanate was treated with excess diaminopentane and the remaining unsubstituted amino group of the product was condensed, via a carbodiimide-promoted reaction, with a carboxyl group of amethopterin . The final product, a fluorescent derivative of amethopterin, was isolated by chromatography on AE-cellulose and preparative electrophoresis on polyacrylamide . It was shown to be homogeneous by analytical polyacrylamide electrophoresis and thin-layer chromatography . Proof of structure was provided by elemental analysis, absorbance spectra (at pH 7.0, lambdamax at 495 nm; fluorescence emission at 520 nm), and 1H NMR measurements . The fluorescent derivative of amethopterin inhibited transport of amethopterin into Lactobacillus casei and L1210 cells . It was also a good inhibitor of the L . casei and L1210 dihydrofolate reductases and could be used to provide a fluorescent label for the enzymes during polyacrylamide electrophoresis. J Dent Res, 1975 May-Jun, 54(3), 500 - 3 In vitro determination of the antimicrobial properties of two cyanoacrylate preparations; Blum GN et al.; Isobutyl and trifluoro cyanoacrylates showed varying degrees of inhibition for Lactobacillus casei and Staphylococcus aureus when tested by the spread plate technique . Candida albicans and Pseudomonas aeruginosa were resistant . The results tend to support the view that inhibition of growth was due to the vapor effect and not the diffusibility of the cyanoacrylates. J Dent Res, 1975 May-Jun, 54(3), 449 - 57 Effect of sodium phytate on the chemical and microbial composition of dental plaque in the monkey (Macaca fascicularis) Cole MF, Bowen WH. The incorporation of 1 or 3% sodium phytate in confectioners sugar produced minimal changes in the physical,chemical, and microbial composition of dental plaque in tube-fed monkeys during a two-week period . Only a reduction in yeasts and lactobacilli could be ascribed to the presence of phytate . Other changes were attributable to the transition from conventional feeding to tube-feeding, irrespective of the presence of absence of phytate. Can J Microbiol, 1975 May, 21(5), 629 - 32 Effect of lactobacilli and carbon dioxide on the growth of Microbacterium thermosphactum on fresh beef; Roth LA et al.; Studies with articifially inoculated fresh beef showed that lactobacilli markedlyrestrict the growth of Microbacterium thermosphactum when the beef is vacuum-packaged . High concentrations of carbon dioxide (up to 75%) had little effect on the growthof M . thermosphactum under either aerobic or anaerobic conditions . Tests were madewith samples of lean beef inoculated with pure cultures of lactobacilli and (or) M . thermosphactum and stored unpackaged in air, in air enriched with carbon dioxide, in nitrogen-carbon dioxide mixtures, or vacuum-packaged as in commercial practice . On vacuum-packaged meat, growth of M . thermosphactum was extensive in the absence of lactorbacilli, but was restricted in the presence of lactobacilli . On unpackaged meat (i.e.stored in air) this inhibition did not occur, showing that anaerobic conditions are necessary for it to take place . These results show the import ance of lactobacilli on the storage life of vacuum-packaged fresh beef. Infect Immun, 1975 May, 11(5), 962 - 8 Distribution of indigenous bacteria in the digestive tract of conventional and gnotobiotic rats; Morotomi M et al.; The localization and population levels of the indigenous bacterial flora of conventional rats were investigated by cultural and histological techniques . Lactobacilli predominate in the stomach and upper part of the small intestine and associate with keratinized cells of the nonglandular portion of stomach . Mixtures of varying complexity of pure cultures of indigenous bacteria were inoculated into germfree rats . The distribution of these bacteria was examined to investigate the effect of lactobacilli in controlling the composition of other bacterial species in each portion of the digestive tract . In the stomach and the upper part of the small intestine, lactobacilli controlled the population levels of other bacterial species . In the lower part of the small intestine, not only lactobacilli but also the anaerobes which colonized the large bowel influenced the population levels of other bacterial types . Staphylococci isolated from a conventional rat colonized specifically the keratinized cells of the nonsecreting epithelium of the stomach when the rats were free from lactobacilli . This colonization was not observed after inoculation of lactobacilli into the rats. Am J Clin Nutr, 1975 May, 28(5), 438 - 44 Nutritional stability of various naturally occurring monoglutamate derivatives of folic acid; O'Broin JD et al.; The nutritional stabilities of four major dietary folates were studied as their corresponding monoglutamates and were compared to pteroylglutamate (folic acid) itself . The study of the monoglutamyl rather than polyglutamyl forms was justified since the former are formed during the course of digestion and also addition of extra glutamyl residues is unlikely to affect the types of nutritional instability associated with these derivatives . Since ability to support growth in Lactobacillus casei is known to reflect nutritional activity in man this organism was used in the stability studies . It was found that pteroylglutamate and 5-formyltetrahydropteroylglutamate had nutritional stabilities of the order of weeks although the stability of the former was decreased by phosphate . Surprisingly 10-formyltetrahydropteroylglutamate was nutritionally more stable than expected, possibly due to its conversion to the more stable oxidized 10-formylpteroylglutamate or to the reduced 5-formyl derivative . In contrast 5-methyltetrahydropteroylglutamate was much less stable nutritionally than expected.Unsubstituted tetrahydropteroylglutamate was most unstable nutritionally but in contrast to the other derivatives examined it was more stable under acidic than basic conditions . Ascorbate was found to be a far superior stabilizing agent than 2-mercaptoethanol at comparable concentrations. Can J Microbiol, 1975 May, 21(5), 633 - 38 N-6-(delta-2-isopentenyl) adenosine: hydrolysis by a mucleosidase isolated from Lactobacillus acidophilus cells; Hordern J et al.; A nucleosidase activity has been isolated from Lactobacillus acidophilus which rapidly hydrolyses N-6 (delta-2-isopentenyl) adenosine to its corresponding base, N-6(delta-2-isopentenyl) adenine . The activity can be distinguished from the spleen exzyme (EC . 2.4.2.1), a purine nucleoside transferase, on the basis of its substrate specificity, electrophoretic behavior, and nondependence on phosphate . The bacterial enzyme hydrolyzes both inosine and isopentenyl adenosine, giving Km values of 63.3muM and 177 muM respectively . The presence of this enzyme in bacteria counts for the rapid conversion of the parent nucleoside to isopentenyl adenine, which has been observed in these cells . The enzyme thus assumes importance as one of the catabolic activities available to the cell for metabolizing the cytokinin, N-6-(delta-2-isopentenyl) adenosine. Biochim Biophys Acta, 1975 Apr 8, 382(4), 657 - 60 Heterogeneous elevation of amino acid transport rates in pantothenate-and lipid-deficient Lactobacillus plantarum; Holden JT et al.; The effect of a pantothenic acid deficiency in Lactobacillus plantarum on the initial rate of amino acid transport was investigated . Although the steady-state accumulation capacity for all amino acids was markedly reduced in pantothenate-deficient cells, initial rates of uptake either were not changed (asparagine, alanine, lysine) or were increased (glutamic acid, aspartic acid leucine) . The findings suggest that a reduction in membrane lipid content heterogeneously affects the operation and/or synthesis of amino acid transport catalysts. Avian Dis, 1975 Apr-Jun, 19(2), 366 - 9 Eimeria brunetti in epithelial cells of the bursa of Fabricius in gnotobiotic chickens; Rodriguez R et al.; Germ-free and conventional chickens were infected with Lactobacillus acidophilus and/or Eimeria brunetti . Germ-free chickens acquiring single infections of E . brunetti were found to have lifecycle stages of the coccidial organism in the bursa of Fabricius. Lab Anim, 1975 Apr, 9(2), 149 - 51 Lactobacillus sp . isolates from mouse livers: saprophyte or potential pathogen? Green CJ, Needham JR, Cooper JE. Over a 3-year sampling period Lactobacillus sp . has been isolated from the livers of barrier-maintained and conventional mice . Serology has failed to detect presence of mouse hepatitis virus antibodies in any of these mice . Histopathological examination revealed only mild fatty change and small monocytic infiltrates. J Gen Microbiol, 1975 Apr, 87(2), 245 - 50 Nature of the determinant responsible for the adhesion of lactobacilli to chicken crop epithelial cells; Fuller R; Using an in vitro method, some factors affecting the attachment of a strain of lactobacillus to chicken crop epithelial cells have been studied . Time of contact beyond 10 min, pH value, age or growth temperature of the bacterial culture, or nature of the energy source in the growth medium had little or no effect on attachment . Heating to 100 degrees C for 10 min, or treatment with EDTA or surface active compounds was also without effect . Treatment with sodium periodate markedly decreased adhesion, proteolytic enzymes had a smaller effect but wheat germ lipase was completely inactive . The pronounced inhibition of adhesion by periodate suggested the invovement of carbohydrate . However, enzymes known to attack carbohydrate substrates were inactive in reducing adhesion . Concanavalin A, which binds specifically to certain sugar residues, reduced attachment . It is suggested that these concanavalin A receptors on the lactobacillus are responsible for its attachment to crop epithelial cells. Can J Microbiol, 1975 Apr, 21(4), 501 - 9 Participation of exogenous thymine and thymidine in deoxyribonucleic acid synthesis in Lactobacillus acidophilus; Sawula RV et al.; The degree of participation (DP) of exogenous thymidine and thymine in overall DNA synthesis was studied in Lactobacillus acidophilus R-26 . The DP of thymidine remains constant under a variety of conditions (except at low thymidine concentrations, when the DP is influenced by deoxyribonucleosides and folic acid) . A 5-bromodeoxyuridine-resistant mutant was isolated, which displayed cross-resistance to 5-bromouracil and a significantly lower DP of thymidine than the parental strain . Thymine was poorly incorporated in the parental strain even in the presence of deoxyribosides . The results of this investigation would be compatible with the possibility of an alternative pathway for thymidylate synthesis other than the known thymidylate synthase pathway.
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