Rapid proton release during flash‐induced oxidation of cytochrome c oxidase

FEBS Letters

Oliveberg, Mikael¹  Nilsson, Thomas¹  Hallén, Stefan¹ 

[1] Department of Biochemistry and Biophysics, Chalmers Institute of Technology and University of Gothenburg, S-412 96 96, Gothenburg, Sweden

关键词: Cytochrome oxidase;    Vesicle;    Flow-flash;    Proton pumping;    Hepes;    4-(2-hydroxyethyl)-1-piperazinesulfonic acid;   

DOI  :  10.1016/0014-5793(90)80062-N

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Protolytic reactions during the reaction between fully reduced cytochrome oxidase and oxygen have been investigated using the flow-flash methodology. Enzyme reconstituted into phospholipid vesicles has been used and pH changes in the extravesicular medium have been detected with the pH indicator Phenol red. The results show the release of protons to the medium with a rate of 9.10² s⁻¹ during reoxidation. The amplitude of the absorption change corresponds to at least one proton per functional unit of cytochrome oxidase.

【 授权许可】

Unknown