title: A D-serine dehydratase acting also on L-serine from Klebsiella pneumoniae.
abstract: D-Serine dehydratase [EC 4.2.1.14] was purified from a strain of Klebsiella pneumoniae 140-fold from crude extract with a yield of 5%. This enzyme catalyzed formation of pyruvate and ammonia not only from D-serine but also from L-serine, and also catalyzed the formation of alpha-ketobutyrate and ammonia from D-threonine. Km values for D-serine, L-serine, and D-threonine were 2.8 mM, 20 mM, and 3.6 mM, respectively. Km for pyridoxal 5'-phosphate was 2.5 micron. The molecular weight was estimated to be 46,000 by Sephadex G-150 gel filtration and 40,000 by SDS-polyacrylamide gel electrophoresis. This enzyme was inducible by D-serine. Induction by casamino acids appeared to depend on the presence of D-serine.
mesh_terms: D004790:Enzyme Induction; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007711:Klebsiella pneumoniae / Q000201:enzymology*; D012695:L-Serine Dehydratase / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D012694:Serine / Q000378:metabolism*; D013237:Stereoisomerism; D013379:Substrate Specificity; D013912:Threonine / Q000378:metabolism
chemical_list: D013912:Threonine; D012694:Serine; D012695:L-Serine Dehydratase