Serotype c Streptococcus mutans mutatable to lactate dehydrogenase deficiency.

S Abhyankar; H J Sandham; K H Chan

doi:10.1177/00220345850640110201

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Serotype c Streptococcus mutans mutatable to lactate dehydrogenase deficiency.

S Abhyankar·H J Sandham·K H Chan

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Abstract

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.

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Acetates Acetic Acid Bacteriological Techniques Dental Plaque Ethanol Glucose Humans L-Lactate Dehydrogenase Lactates Lactic Acid Methylnitronitrosoguanidine Mutation Serotyping Streptococcus mutans Sucrose Journal Article Research Support, Non-U.S. Gov't

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S Abhyankar, H J Sandham, K H Chan. 1985. Serotype c Streptococcus mutans mutatable to lactate dehydrogenase deficiency.. https://doi.org/10.1177/00220345850640110201

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