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Time-resolved surface-enhanced IR-absorption spectroscopy of direct electron transfer to cytochrome c oxidase from R. sphaeroides.

ABSTRACT: Time-resolved surface-enhanced IR-absorption spectroscopy triggered by electrochemical modulation has been performed on cytochrome c oxidase from Rhodobacter sphaeroides. Single bands isolated from a broad band in the amide I region using phase-sensitive detection were attributed to different redox centers. Their absorbances changing on the millisecond timescale could be fitted to a model based on protonation-dependent chemical reaction kinetics established previously. Substantial conformational changes of secondary structures coupled to redox transitions were revealed.

SUBMITTER: Schwaighofer A

PROVIDER: S-EPMC3882501 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Time-resolved surface-enhanced IR-absorption spectroscopy of direct electron transfer to cytochrome c oxidase from R. sphaeroides.

Schwaighofer Andreas A Steininger Christoph C Hildenbrandt David M DM Srajer Johannes J Nowak Christoph C Knoll Wolfgang W Naumann Renate L C RL

Biophysical journal 20131201 12

Time-resolved surface-enhanced IR-absorption spectroscopy triggered by electrochemical modulation has been performed on cytochrome c oxidase from Rhodobacter sphaeroides. Single bands isolated from a broad band in the amide I region using phase-sensitive detection were attributed to different redox centers. Their absorbances changing on the millisecond timescale could be fitted to a model based on protonation-dependent chemical reaction kinetics established previously. Substantial conformational ...[more]

PMID: 24359742

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