[Spectral transformations in purple membranes of Halobacterium halobium: effect of 560-570 transition and blue light...

Effect of reversible photodependent spectral transition 560 in equilibrium 570 of the basic absorption band in purpur membranes (PM) in water on the accumulation of short-living forms 412 and 650 of bacteriorhodopsin (BR) photochemical cycle was studied. It has been shown that photochemical transformations in BR proceed as a minimum by two independent cycles, whose initial spectral forms were represented by BR with retinene in the form 13 cis and BR with retinene in the form of trans. In the course of the transition 560-- greater than 570 a long-living spectral form 370--410--430 sensitive to the blue light is formed. On the basis of our own and literature data a new scheme of photochemical processes in PM was suggested and connection between some stages of these processes and ejection and absorption of PM protones proposed.