Inhibition of the M1→M2 (Mclosed→Mopen) transition in the D96N mutant photocycle and its relation to the corresponding transition in wild‐type bacteriorhodopsin

FEBS Letters

Radionov, Alexey N¹  Kaulen, Andrey D¹ 

[1] Department of Photobiochemistry, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119899 Moscow, Russia

关键词: Bacteriorhodopsin;    Photocycle;    Proton transport;    Azide;    Purple membrane;    D96N mutant;    Halobacterium salinarium;    bR;    bacteriorhodopsin;    GA;    glutaraldehyde;    PM;    purple membrane;   

DOI  :  10.1016/S0014-5793(97)00474-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Glutaraldehyde, lutetium ions and glycerol inhibit the blue shift of the difference spectra maximum of the M intermediate in the D96N mutant. The M formed has a spectrum indistinguishable from the M intermediate in wild-type bacteriorhodopsin. It has been concluded that the M_open form previously described by us is identical to the M2 and M_n intermediates postulated by Zimanyi et al. (Photochem. Photobiol. (1992) 56, 1049–1055) and Sasaki et al. (J. Biol. Chem. (1992) 267, 20782–20786), respectively. It is supposed that its formation is accompanied by the appearance of the cytoplasmic proton half-channel. M_open in the wild-type protein is present in a very low amount due to the shift of the M_closed↔M_open equilibrium towards the M_closed. The inhibitors used do not prevent the multiphase pattern of the M formation in either mutant or wild-type proteins.

【 授权许可】

Unknown