Properties of Nicotinamide Adenine Dinucleotide Phosphate-Dependent Formate Dehydrogenase from Clostridium thermoaceticum

Abstract

Li, Lan-Fun (Western Reserve University School of Medicine, Cleveland, Ohio), Lars Ljungdahl, and Harland G. Wood . Properties of nicotinamide adenine dinucleotide phosphate-dependent formate dehydrogenase from Clostridium thermoaceticum . J. Bacteriol. 92: 405–412. 1966.—A nicotinamide adenine dinucleotide phosphate (NADP)-dependent formate dehydrogenase has been isolated from C. thermoaceticum . The enzyme is very sensitive to oxygen and requires sulfhydryl compounds for activity. The apparent K m at 50 C and p H 7.0 for NADP is 5.9 × 10 −5 m and for formate, 2.2 × 10 −4 m . The enzyme is most active at about 60 C and at p H values between 7.0 and 9.0. The enzyme catalyzes an exchange between C 14 O 2 and formate, which requires NADP, but net synthesis of formate from CO 2 and reduced nicotinamide adenine dinucleotide phosphate could not be demonstrated. The reaction does not involve ferredoxin.