Serotype c Streptococcus mutans mutatable to lactate dehydrogenase deficiency.
Three lactate-dehydrogenase-deficient mutants of serotype c S. mutans were made by using, as parents, two serotype c strains that produced unusually large amounts of ethanol, acetic acid, and acetoin, and very little lactic acid, when grown in broth containing a limiting amount of glucose. The mutants, obtained with N-methyl-N'-nitro-N-nitrosoguanidine, were stable during 12 weeks of daily subculture in broth. Crude cell-free extracts of the mutants had less than 1% of the LDH-specific activity of their parent strains. The serotype c mutants resembled serotype g mutants in having molar growth yields at least as high as those of their parents. However, in contrast to the g mutants, the c mutants produced cell crops (cell mass per ml medium) that were as high as those of their parent strains.
D000085:Acetates / Q000378:metabolism; D019342:Acetic Acid; D001431:Bacteriological Techniques; D003773:Dental Plaque / Q000382:microbiology; D000431:Ethanol / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000172:deficiency* / Q000378:metabolism; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D009154:Mutation; D012703:Serotyping; D013295:Streptococcus mutans / Q000145:classification / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
D000085:Acetates; D007773:Lactates; D008769:Methylnitronitrosoguanidine; D019344:Lactic Acid; D000431:Ethanol; D013395:Sucrose; D007770:L-Lactate Dehydrogenase; D005947:Glucose; D019342:Acetic Acid