A novel NADP(+)-dependent serine dehydrogenase from Agrobacterium tumefaciens.
NADP(+)-dependent serine dehydrogenase [EC 1.1.1.-], which catalyzes the oxidation of the hydroxyl group of serine to form 2-aminomalonate semialdehyde, was purified to homogeneity from a crude extract of Agrobacterium tumefaciens ICR 1600. The enzyme had a molecular mass of about 100 kDa and consisted of four identical subunits. In addition to L-serine, D-serine, L-glycerate, D-glycerate, and 2-methyl-DL-serine were substrates. However, O-methyl-DL-serine and L-threonine were inert. The enzyme showed maximal activity at about pH 9 for the oxidation of L-serine. The enzyme required NADP+ as a coenzyme, NAD+ was inert. The enzyme was not inhibited by EDTA, o-phenanthroline, or alpha,alpha'-dipyridyl, but was inhibited by HgCl2, p-chloromercuribenzoate, L-cysteine, D-cysteine, malonate, 2-methylmalonate, and tartronate. The Michaelis constants for L-serine, D-serine, and NADP+ were 42, 44, and 0.029 mM, respectively.
Chowdhury
E K
EK
Department of Bioresources Science, Kochi University, Japan.
Higuchi
K
K
Nagata
S
S
Misono
H
H
D000042:Absorption; D016960:Agrobacterium tumefaciens / Q000737:chemistry / Q000201:enzymology*; D000429:Alcohol Oxidoreductases / Q000737:chemistry* / Q000378:metabolism; D000595:Amino Acid Sequence; D002237:Carbohydrate Dehydrogenases / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004795:Enzyme Stability; D007700:Kinetics; D007709:Klebsiella / Q000201:enzymology; D008670:Metals / Q000494:pharmacology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009249:NADP / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D050543:Phosphoglycerate Dehydrogenase; D011549:Pseudomonas / Q000201:enzymology; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000378:metabolism
D004791:Enzyme Inhibitors; D008670:Metals; D010446:Peptide Fragments; D009249:NADP; D000429:Alcohol Oxidoreductases; D002237:Carbohydrate Dehydrogenases; C104535:NADP+-dependent serine dehydrogenase; D050543:Phosphoglycerate Dehydrogenase; D012697:Serine Endopeptidases; C036813:lysyl endopeptidase