Photoelectric response of the N intermediate of bacteriorhodopsin and its mutant T46V

Double flash experiments were performed in order to gain information about the characteristics of the N intermediates of the photocycle of bacteriorho dopsin, The N intermediates of wild-type bacteriorhodopsin and mutant T46V mere excited at different delay times after the first laser flash which ind uced the photocycle and the electric responses were registered, These elect ric signals revealed that charge motions occurred in both cases, though cha rge translocation, i.e. H+ pumping, could not be observed. The delay time d ependence of the electric signals is characterized by two distinct processe s corresponding to two substates of the N intermediates. (C) 1999 Federatio n of European Biochemical Societies.