Characterization of the Ni-Fe-C complex formed by reaction of carbon monoxide with the carbon monoxide dehydrogenase from Clostridium thermoaceticum by Q-band ENDOR

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00216a018· OSTI ID:5526387

Fan, Chaoliang; Hoffman, B M ^[1]; Gorst, C M; Ragsdale, S W ^[2]

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1. Northwestern Univ., Evanston, IL (USA)
2. Univ. of Wisconsin, Milwaukee (USA)

Q-Band ENDOR studies on carbon monoxide dehydrogenase (CODH) from the acetogenic bacterium Clostridium thermoaceticum provided unambiguous evidence that the reaction of CO with CODH produces a novel metal center that includes at least one nickel, at least three iron sites, and the carbon of one CO. The {sup 57}Fe hyperfine couplings determined by ENDOR are similar to the values used in simulation of the Mossbauer spectra. EPR simulation using these A{sup Fe} values is equally good for a 4Fe or a 3Fe center. The {sup 13}C ENDOR data are consistent with the binding of a carbon atom to either the Ni or the Fe component of the spin-coupled cluster. The {sup 13}C hyperfine couplings are similar to those determined earlier for the CO-bound form of the H cluster of the Clostridium pasteurianum hydrogenase, proposed to be the active site of hydrogen activation. The {sup 61} Ni ENDOR data are the first nickel ENDOR recorded for an enzyme. The EPR simulation using the ENDOR-derived hyperfine values for {sup 61}Ni is consistent with a single nickel site in the Ni-Fe-C complex. On the basis of our results and the Mossbauer data the authors propose the stoichiometry of the components of the Ni-Fe-C complex to be Ni{sub 1}Fe{sub 3-4}S{sub {ge}}4C{sub 1}, with four acid-labile sulfides.

• DOE Contract Number: FG02-88ER13875
• OSTI ID: 5526387
• Journal Information: Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 30:2; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
BACTERIA
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON 13
CARBON COMPLEXES
CARBON COMPOUNDS
CARBON ISOTOPES
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CLOSTRIDIUM
COMPLEXES
ELECTRON SPIN RESONANCE
ENDOR
ENZYMES
EVEN-ODD NUCLEI
HAEM DEHYDROGENASES
HYPERFINE STRUCTURE
INTERMEDIATE MASS NUCLEI
IRON 57
IRON COMPLEXES
IRON ISOTOPES
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MICROORGANISMS
MOLECULAR STRUCTURE
NICKEL 63
NICKEL COMPLEXES
NICKEL ISOTOPES
NUCLEI
OXIDATION
OXIDES
OXIDOREDUCTASES
OXYGEN COMPOUNDS
RADIOISOTOPES
RESONANCE
STABLE ISOTOPES
TRANSITION ELEMENT COMPLEXES
YEARS LIVING RADIOISOTOPES