Chemical dynamics in proteins: the photoisomerization of retinal in bacteriorhodopsin.

Gai, F; Hasson, K C; McDonald, J C; Anfinrud, P A · Science · 1998

basic_science · Level V

Where this comes from

Abstract

Chemical dynamics in proteins are discussed, with bacteriorhodopsin serving as a model system. Ultrafast time-resolved methods used to probe the chemical dynamics of retinal photoisomerization in bacteriorhodopsin are discussed, along with future prospects for ultrafast time-resolved crystallography. The photoisomerization of retinal in bacteriorhodopsin is far more selective and efficient than in solution, the origins of which are discussed in the context of a three-state model for the photoisomerization reaction coordinate. The chemical dynamics are complex, with the excited-state relaxation exhibiting a multiexponential decay with well-defined rate constants. Possible origins for the two major components are also discussed.

Medical subject headings