Purification and properties of NADP-dependent formate dehydrogenase from Clostridium thermoaceticum, and tungsten-selenium-iron protein
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), Vol. 258:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ionization of isocitrate bound to pig hear NADP/sup +/-dependent isocitrate dehydrogenase: /sup 13/C NMR study of substrate binding
Macromolecular organization of F/sub 1/-ATPase isolated from Clostridium thermoaceticum as revealed by electron microscopy
Related Subjects
OXIDOREDUCTASES
CHEMICAL PROPERTIES
EMISSION SPECTRA
ENZYME ACTIVITY
CLOSTRIDIUM
ELECTROPHORESIS
FORMATES
IRON
NADP
OXYGEN
SELENIUM
TUNGSTEN
BACTERIA
CARBOXYLIC ACID SALTS
COENZYMES
ELEMENTS
ENZYMES
METALS
MICROORGANISMS
NONMETALS
NUCLEOTIDES
ORGANIC COMPOUNDS
SEMIMETALS
SPECTRA
TRANSITION ELEMENTS
550200* - Biochemistry
550700 - Microbiology