Different polypeptides of bovine heart cytochrome c oxidase are in contact with cytochrome c

FEBS Letters

Montecucco, Cesare¹  Bisson, Roberto¹ 

[1] Centro C.N.R. per la Fisiologia dei Mitocondri e Laboratorio di Biologia e Patologia Molecolare, Istituto di Patologia Generale, Via Loredan 16, 35100 Padova, Italy

关键词: Cytochrome c oxidase;    Cytochrome c;    Cross-linking;    Protein modification;    Carbodiimide;   

DOI  :  10.1016/0014-5793(82)81302-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Two water-soluble carbodiimides, differing in molecular dimensions, have been used to characterize the cytochrome c binding site of bovine heart cytochrome c oxidase. Several polypeptide components of the enzyme contain acidic residues which are modified by these reagents. Carboxyl groups present in subunit II, VII and polypeptide c, are protected from modification when cytochrome c, equimolar to oxidase, is added and they can cross-link to the substrate once activated by the carbodiimide. Comparison of the modification patterns suggest that the most reactive residues are located on subunit II and VII, the former being also more exposed. The data obtained indicate that eventhough subunit II plays the major role in binding cytochrome c, at least two other lower M _r polypeptides contribute to the cytochrome c binding domain.

【 授权许可】

Unknown