REVIEW: Similarities and Differences in Photochemistry of Type I and Type II Rhodopsins

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Mikhail A. Ostrovsky^1,2, Olga A. Smitienko², Anastasia V. Bochenkova³, and Tatiana B. Feldman^1,2,a*

¹Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia

²Emanuel Institute of Biochemical Physics, 119334 Moscow, Russia

³Faculty of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia

^* To whom correspondence should be addressed.

Received July 1, 2023; Revised July 20, 2023; Accepted August 12, 2023

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The diversity of the retinal-containing proteins (rhodopsins) in nature is extremely large. Fundamental similarity of the structure and photochemical properties unites them into one family. However, there is still a debate about the origin of retinal-containing proteins: divergent or convergent evolution? In this review, based on the results of our own and literature data, a comparative analysis of the similarities and differences in the photoconversion of the rhodopsin of types I and II is carried out. The results of experimental studies of the forward and reverse photoreactions of the bacteriorhodopsin (type I) and visual rhodopsin (type II) rhodopsins in the femto- and picosecond time scale, photo-reversible reaction of the octopus rhodopsin (type II), photovoltaic reactions, as well as quantum chemical calculations of the forward photoreactions of bacteriorhodopsin and visual rhodopsin are presented. The issue of probable convergent evolution of type I and type II rhodopsins is discussed.

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KEY WORDS: retinal-containing proteins, visual rhodopsin, bacteriorhodopsin, convergent evolution, photochemistry, femtosecond spectroscopy, quantum chemical calculations

DOI: 10.1134/S0006297923100097

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