title: Purification and properties of nicotinamide adenine dinucleotide-dependent D- and L- lactate dehydrogenases in a group N streptococcus.
abstract: Streptococcus lactis strain 760, a group N streptococcus, was found to possess nicotinamide adenine dinucleotide-dependent dehydrogenase activities for both the l(+) and the d(-) isomers of lactic acid. The two enzymes were isolated and purified and were found to differ with respect to pH optima, activation by fructose-1,6-diphosphate, pH and heat stability, and the temperature at which each enzyme was formed in the organism during growth. The presence of a racemase for lactic acid was not detected by the methods used.
mesh_terms: D000645:Ammonium Sulfate; D002474:Cell-Free System; D011232:Chemical Precipitation; D002852:Chromatography, Ion Exchange; D003470:Culture Media; D004789:Enzyme Activation; D005636:Fructosephosphates / Q000494:pharmacology; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007770:L-Lactate Dehydrogenase / Q000302:isolation & purification / Q000378:metabolism; D007773:Lactates / Q000378:metabolism; D013294:Lactococcus lactis / Q000201:enzymology / Q000378:metabolism; D009243:NAD / Q000378:metabolism*; D010084:Oxidation-Reduction; D011773:Pyruvates / Q000378:metabolism; D013237:Stereoisomerism; D013291:Streptococcus / Q000201:enzymology*
chemical_list: D003470:Culture Media; D005636:Fructosephosphates; D007773:Lactates; D011773:Pyruvates; D009243:NAD; D007770:L-Lactate Dehydrogenase; D000645:Ammonium Sulfate