[Interaction of rhodopsin with quinone].

The reaction of rodopsin extracted with cetyltrimethylammonium bromide with p-benzoquinone was studied with spectrophotometric and ESR methods. In the dark quinone reacted with three SH-groups of rodopsin, in the light with three more SH- and two unknown groups of decolourized rodopsin. The interaction of quinone with SH-groups liberated under light effect on rodopsin proceeds with the formation of intermediate free-radical products.