Bacteriorhodopsin/amphipol complexes: structural and functional properties.
نویسندگان
چکیده
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.
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ورودعنوان ژورنال:
- Biophysical journal
دوره 94 9 شماره
صفحات -
تاریخ انتشار 2008