FORMIC ACID DEHYDROGENASE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain a new formic acid dehydrogenase derived from a microorganism belonging to the genus Hyphomicrobium, catalyzing a reaction oxidizing formic acid and producing carbonic acid and having high specific activity and small Km value to formic acid and NAD+ and wide ranges of temperature stability and pH stability. SOLUTION: This new formic acid dehydrogenase enzyme has the following physicochemical properties. Range of acting temperature: 20-70 deg.C; optimum temperature: 50 deg.C; range of acting pH: 4-10; optimum pH: 6.0-7.5; molecular weight: about 80,000 (by gel filtration chromatographic method); Km value to formic acid: 1.06 mM; Km value to NAD+: 0.05 mM; temperature stability: <=55 deg.C; pH stability: pH 6.5-8.5; action: catalyzing a reaction oxidizing (dehydrogenating) formic acid and producing carbonic aicd. The enzyme is obtained by culturing a microorganism belonging to the genus Hyphomicrobium and having producing ability of the above enzyme [e.g. Hyphomicrobium espi J17 (FER P-16973)] in a culture medium and collecting a product in cultured product in the culture medium.