Enzymatic activities involved in glucose fermentation of Actinomyces naeslundii were studied with glucose-grown cells from batch cultures. Glucose could be phosphorylated to glucose 6-phosphate by a glucokinase that utilized polyphosphate and GTP instead of ATP as a phosphoryl donor. Glucose 6-phosphate was further metabolized to the end products lactate, formate, acetate, and succinate through...

was developed by using 2'-(4-methylumbelliferyl)oa-D-N-acetylneuraminic acid as substrate in a filter paper spot test. The method was compared to conventional assays that use 2'-(4-methylumbelliferyl)ax-D-N-acetylneuraminic acid and bovine submaxillary mucin and was found to be in excellent agreement. Organisms with >10 U of enzyme activity (in nanomoles per minute per milligram of cell protein...

Cell-mediated immunity in humans to antigens derived from oral plaque bacteria was investigated by using the lymphocyte blastogenesis assay. Subjects with varying severities of periodontal disease including normal, gingivitis, periodontitis, and edentulous were compared. Mononuclear leukocytes were separated from peripheral blood and cultured with antigens prepared by sonication of Actinomyces ...

Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative microorganisms responsible for dental root canal infections. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Porphyromonas gingiva...

Local and systemic administrations of tetracycline have been used in human periodontal treatment for conditions including juvenile periodontitis and rapidly progressive periodontitis, although microbiological effects of the treatment have not been clear. The effect of systemic oral administration of tetracycline on subgingival bacteria in experimental periodontal disease in hamsters as an anima...

Streptococcus downii is a recently reported bacterial species of oral origin, with inhibitory capacity against mutans, Actinomyces naeslundii, Veillonella parvula and Aggregatibacter actinomycetemcomitans, which confers upon it the potential being an probiotic. The aim present study was to identify mechanisms by S. exerts its effect on mutans. To this end, assessed consumption glucose proteins ...