A cooperative model for protonmotive heme‐copper oxidases. The role of heme a in the proton pump of cytochrome c oxidase

FEBS Letters

Villani, Gaetano¹  Capitanio, Nazzareno¹  Papa, Sergio¹ 

[1] Institute of Medical Biochemistry and Chemistry, University of Bari, Policlinico, Piazza Giulio Cesare, 70124 Bari, Italy

关键词: Cytochrome c oxidase;    Proton pump;    Cooperative coupling;   

DOI  :  10.1016/S0014-5793(98)01305-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Oxido-reductions of metal centers in cytochrome c oxidase are linked to pK shifts of acidic groups in the enzyme (redox Bohr effects). The linkage at heme a results in proton uptake from the inner space upon reduction and proton release in the external space upon oxidation of the metal. The relationship of this process to the features of the proton pump in cytochrome c oxidase and its atomic structure revealed by X-ray crystallography to 2.8–2.3 Å resolution is examined. A mechanism for the proton pump of cytochrome c oxidase, based on cooperative coupling at heme a, is proposed.

【 授权许可】

Unknown