Purification and properties of two malate dehydrogenases from Candida sp. N-16 grown on methanol.
Two malate dehydrogenases (MDH-M1 and MDH-M2) were found in a methanol-using yeast, Candida sp. N-16. MDH-M2 was induced with methanol. These enzymes were purified as electrophoretically and isoelectrophoretically homogeneous proteins. The molecular weights of MDH-M1 and MDH-M2 were estimated to be about 78,000 (homodimer) and 160,000 (homotetramer). Several kinetic properties were significantly different between the two enzymes. The value (2.07) of Vmax(oxaloacetate)/Vmax(malate) and Kcats (555 s(-1) for oxaloacetate, 481 s(-1) for NADH) of MDH-M2 were higher than the ratio (1.37) of Vmax and Kcats (241 s(-1) for oxaloacetate, 271 s(-1) for NADH) of MDH-M1, respectively. The activity of MDH-M2 was inhibited by a high concentration of NAD+ and the activity of MDH-M1 by oxaloacetate.
Yoshikawa
J
J
Department of Bioresources Science, Graduate School of Science and Technology, Chiba University, Matsudo-shi, Japan.
Seki
K
K
Shinoyama
H
H
Fujii
T
T
D002175:Candida / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism; D007527:Isoenzymes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D008291:Malate Dehydrogenase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D000432:Methanol / Q000378:metabolism; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism; D062907:Oxaloacetic Acid / Q000378:metabolism; D020836:Protein Structure, Quaternary
D007527:Isoenzymes; D009243:NAD; D062907:Oxaloacetic Acid; D008291:Malate Dehydrogenase; D000432:Methanol