Selective Choice of the Efficient Carotenoid Antenna by a Xanthorhodopsin: Controlling Factors for Binding and Excitation Energy Transfer.

ABSTRACT: Despite extensive research on carotenoids and microbial rhodopsins in aquatic environments, a fundamental understanding of the binding requirements of carotenoids that serve as auxiliary light-harvesting antennas for rhodopsins is still lacking. Our recent discovery of 3-hydroxylated xanthophyll-binding proteorhodopsins and xanthorhodopsins prompted us to investigate the role of keto and hydroxy functional groups in carotenoid binding to rhodopsins and their influence on energy transfer to the retinal chromophore. In this study, we examined the binding of 12 carotenoids to rhodopsin Kin4B8 (a protein of the xanthorhodopsin family, GenBank: OP056329) and assessed the energy transfer between the carotenoid and the retinal chromophore. We found that 3-hydroxylated xanthophylls were the most e

SUBMITTER: Das I 

PROVIDER: S-EPMC12308411 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature