Thermal stability of squid rhodopsin in photoreceptor membrane and their triton extracts

Abstract

Kinetic parameters of the thermal decay of squid rhodopsin in isolated photoreceptor membranes and in a 1% Triton X-100 solution have been determined. It has been shown that the treatment with Triton X-100 considerably decreases thermal stability of rhodopsin. Addition of hydroxylamine (0.5 m) to Triton X-100 solutions leads to further decrease of rhodopsin thermostability. When Triton extracts are exposed to light, bleaching of visual pigments occurs at room temperature.