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Bacteriorhodopsin/amphipol complexes: structural and functional properties.

ABSTRACT: The membrane protein bacteriorhodopsin (BR) can be kept soluble in its native state for months in the absence of detergent by amphipol (APol) A8-35, an amphiphilic polymer. After an actinic flash, A8-35-complexed BR undergoes a complete photocycle, with kinetics intermediate between that in detergent solution and that in its native membrane. BR/APol complexes form well defined, globular particles comprising a monomer of BR, a complete set of purple membrane lipids, and, in a peripheral distribution, approximately 2 g APol/g BR, arranged in a compact layer. In the absence of free APol, BR/APol particles can autoassociate into small or large ordered fibrils.

SUBMITTER: Gohon Y

PROVIDER: S-EPMC2292372 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Bacteriorhodopsin/amphipol complexes: structural and functional properties.

Gohon Yann Y Dahmane Tassadite T Ruigrok Rob W H RW Schuck Peter P Charvolin Delphine D Rappaport Fabrice F Timmins Peter P Engelman Donald M DM Tribet Christophe C Popot Jean-Luc JL Ebel Christine C

Biophysical journal 20080111 9

The membrane protein bacteriorhodopsin (BR) can be kept soluble in its native state for months in the absence of detergent by amphipol (APol) A8-35, an amphiphilic polymer. After an actinic flash, A8-35-complexed BR undergoes a complete photocycle, with kinetics intermediate between that in detergent solution and that in its native membrane. BR/APol complexes form well defined, globular particles comprising a monomer of BR, a complete set of purple membrane lipids, and, in a peripheral distribut ...[more]

PMID: 18192360

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