Identification of a cysteine involved in the interaction between carbon monoxide dehydrogenase and corrinoid/Fe‐S protein from Clostridium thermoaceticum

FEBS Letters

Kumar, Ganesh K.¹  Shanmugasundaram, T.¹  Sundaresh, C.S.¹ 

[1] Department of Biochemistry, Case Western Reserve University, Cleveland, OH 44106, USA

关键词: Carbon monoxide dehydrogenase;    Corrinoid;    Protein—protein interaction;    Acetyl-CoA synthesis;    Protein complex;    Clostridium thermoaceticum;    CODII;    carbon monoxide dehydrogenase;    NEM;    N-ethylmaleimide;    TFA;    trifluoroacetic acid;    Corrinoid;    corrinoid/Fe-S protein;    HS-CoM;    methyl coenzyme M;   

DOI  :  10.1016/0014-5793(93)81808-D

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In Clostridium thermoaceticum, the synthesis of acetyl-CoA from methyl tetrahydrofolate occurs via a series of enzymatic reactions involving methyl transferase, corrinoid/Fe-S protein (corrinoid), carbon monoxide dehydrogenase (CODH) and ferredoxin. We have investigated the possibility of one or more of these proteins existing as multi-enzyme complexes in vivo with higher catalytic activity. A protein complex consisting of CODH and corrinoid was isolated from the cell-free extracts of Clostridium thermoaceticum. The acetyl-CoA synthesis was found to be ∼ 1.8-fold higher with the complex than that observed with the isolated protein components. HPLC gel filtration analyses of the native and DTE reduced complex suggested that the CODH:corrinoid complex is held together primarily by an inter disulfide bond. By differential labeling of thiols with [¹⁴C]N-ethylmaleimide it was found that Cys-506 of the α subunit of CODH was involved in the disulfide linkage with the corrinoid of the complex.

【 授权许可】

Unknown