Aspartate dehydrogenase in vitamin B12-producing Klebsiella pneumoniae IFO 13541.
We found a new reaction of aspartic acid dehydrogenation, catalyzed by NADP(+)-dependent aspartate dehydrogenase, in vitamin B12-producing Klebsiella pneumoniae IFO 13541. The enzyme, which was purified from a crude extract of K.pneumoniae IFO 13541, catalyzes the oxidative deamination of aspartic acid to form oxaloacetic acid. This enzyme had a molecular mass of about 124 kDa consisting of two identical subunits. L-Aspartic acid was a substrate, although D-aspartic acid and L-glutamic acid were inactive. The enzyme showed maximal activity at about pH 7.0-8.0 for the oxidative deamination of L-aspartic acid, and it required NADP+ as a coenzyme, while NAD+ was inactive.
Okamura
T
T
Department of Food Science and Nutrition, School of Human Environmental Sciences, Mukogawa Women's University, Nishinomiya, Japan.
Noda
H
H
Fukuda
S
S
Ohsugi
M
M
D000594:Amino Acid Oxidoreductases / Q000302:isolation & purification* / Q000378:metabolism; D000641:Ammonia / Q000032:analysis; D000645:Ammonium Sulfate / Q000737:chemistry; D001224:Aspartic Acid / Q000032:analysis / Q000378:metabolism*; D002847:Chromatography, Agarose; D002848:Chromatography, DEAE-Cellulose; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000378:metabolism*; D008970:Molecular Weight; D009249:NADP / Q000378:metabolism; D010071:Oxaloacetates / Q000032:analysis; D011479:Protamines / Q000737:chemistry; D014805:Vitamin B 12 / Q000096:biosynthesis*
D010071:Oxaloacetates; D011479:Protamines; D001224:Aspartic Acid; D009249:NADP; D000641:Ammonia; D000594:Amino Acid Oxidoreductases; C025745:aspartate dehydrogenase; D014805:Vitamin B 12; D000645:Ammonium Sulfate