Purification and properties of NADP-dependent formate dehydrogenase from Clostridium thermoaceticum, and tungsten-selenium-iron protein

Journal Article · Thu Feb 10 04:00:00 EST 1983 · J. Biol. Chem.; (United States)

OSTI ID:5975702

Yamamoto, I; Saiki, T; Liu, S M; Ljungdahl, L G

NADP-dependent formate dehydrogenase (NADP/sup +/) from Clostridium thermoaceticum has been purified to a specific activity of about 1100 ..mu..mol min/sup -1/ mg/sup -1/ when assayed at 55/sup 0/C and pH 7.5. The enzyme is extremely oxygen-sensitive. Purification was done in an atmosphere at 95% N/sub 2/ and 5% H/sub 2/ and by including azide, dithionite, and glycerol as stablizing agents in all buffer solutions. The enzyme contains, in molar ratios, 2 tungsten, 2 selenium, 36 iron, and about 50 inorganic sulfur. It has a molecular weight of about 340,000 and consist of two each of two different subunits giving the composition ..cap alpha../sub 2/..beta../sub 2/. The molecular weight of the ..cap alpha..-subunit is 96,000 and that of the ..beta..-subunit is 76,000. The selenium resides in the two..cap alpha..-subunits. Tungsten is released from the cofactor. The enzyme catalyzes a reduction of CO/sub 2/ with NADPH at pH 7.5 and 55/sup 0/C.

• Research Organization: Univ. of Georgia, Athens
• DOE Contract Number: AS09-79ER10499
• OSTI ID: 5975702
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 258:3; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
550700 -- Microbiology
59 BASIC BIOLOGICAL SCIENCES
BACTERIA
CARBOXYLIC ACID SALTS
CHEMICAL PROPERTIES
CLOSTRIDIUM
COENZYMES
ELECTROPHORESIS
ELEMENTS
EMISSION SPECTRA
ENZYME ACTIVITY
ENZYMES
FORMATES
IRON
METALS
MICROORGANISMS
NADP
NONMETALS
NUCLEOTIDES
ORGANIC COMPOUNDS
OXIDOREDUCTASES
OXYGEN
SELENIUM
SEMIMETALS
SPECTRA
TRANSITION ELEMENTS
TUNGSTEN