RT Journal Article
T1 Selective Choice of the Efficient Carotenoid Antenna by a Xanthorhodopsin: Controlling Factors for Binding and Excitation Energy Transfer
A1 Das, Ishita
A1 León Bañares, Rosa María
A1 Gómez Villegas, Patricia
A1 Sheves, Mordechai
AB 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 effective light-harvesting antennas among the carotenoids studied. While 4-ketocarotenoids also bound to the protein, their energy transfer efficiency was significantly reduced. In contrast, the presence of a 4-hydroxy group or the substitution of the β-ionone ring by an ε-ionone ring completely prevented binding. Furthermore, mutagenesis studies of Kin4B8 suggest that specific residues play a key role in the selective binding of carotenoids. These findings provide valuable insights into the structural determinants of rhodopsin-carotenoid interactions, which may aid in predicting the recruitment of various carotenoid antennas by retinal proteins.
PB American Chemical Society
SN 2691-3704 (electrónico)
YR 2025
FD 2025
LK https://hdl.handle.net/10272/27536
UL https://hdl.handle.net/10272/27536
LA eng
NO Das, I., Chazan, A., Church, J. R., Larom, S., León, R., Gómez-Villegas, P., Bárcenas-Pérez, D., Cheel, J., Koblížek, M., Béjà, O., Schapiro, I., & Sheves, M. (2025). Selective Choice of the Efficient Carotenoid Antenna by a Xanthorhodopsin: Controlling Factors for Binding and Excitation Energy Transfer. JACS Au, 5(7), 3070–3081. https://doi.org/10.1021/jacsau.4c01243
NO This work was supported by the Kimmelman Center for Biomolecular Structure and Assembly (M.S.), the Israel Science Foundation (Research Center grant 3131/20 to I.S. & O.B.), the Nancy and Stephen Grand Technion Energy Program (GTEP), the Agencia Estatal de Investigación (grant PID2022-140995OB-C21 by MICIU/AEI/10.13039/ 501100011033 and ERDF/EU to R.L.), the Czech Science Foundation (project 25-16833S to M.K.), the GIF NEXUS No. I-1560-207.9/2023 (O.B. & I.S.), by the German Research Foundation (CRC 1078−Protonation Dynamics in Protein Function; Project C6 to I.S.). O.B. holds the Louis and Lyra Richmond Chair in Life Sciences and M.S. holds the Katzir- Makineni Chair in Chemistry.
DS Repositorio Institucional de la Universidad de Huelva
RD 1 jun 2026