Bathorhodopsin intermediates from 11-cis-rhodopsin and 9-cis-rhodopsin.

Abstract

Bathorhodopsin-rhodopsin difference spectra of native 11-cis-rhodopsin and regenerated 9-cis-rhodopsin [from bovine retina] were measured at room temperature with a double-beam laser spectrophotometer after excitation at 532 nm. A detailed analysis of data obtained at 85 ps after suggests tha the bathorhodopsins generated from 11 -cis- and 9-cis-rhodopsin differ in their extinction coefficients and that their absorption maxima were shifted in wavelength by .apprx. 10 nm from one another. The ratio of quantum yields for photochemical production of the 11-cis-bathorhodopsin and the 9-cis-bathorhodopsin approximates 1. Implications that the early photochemical processes in vision are more complex than previously considered were explored.