8I2Z

Cryo-EM structure of the zeaxanthin-bound kin4B8

Summary for 8I2Z

• Entry DOI: 10.2210/pdb8i2z/pdb
• EMDB information: 35143
• Descriptor: Xanthorhodopsin, RETINAL, Zeaxanthin, ... (4 entities in total)
• Functional Keywords: rhodopsin, cryo-em, anntena, proton transport
• Biological source: uncultured Bdellovibrionales bacterium
• Total number of polymer chains: 1
• Total formula weight: 29599.15

Authors

Murakoshi, S.,Chazan, A.,Shihoya, W.,Beja, O.,Nureki, O. (deposition date: 2023-01-15, release date: 2023-03-29, Last modification date: 2025-07-02)

Primary citation

Chazan, A.,Das, I.,Fujiwara, T.,Murakoshi, S.,Rozenberg, A.,Molina-Marquez, A.,Sano, F.K.,Tanaka, T.,Gomez-Villegas, P.,Larom, S.,Pushkarev, A.,Malakar, P.,Hasegawa, M.,Tsukamoto, Y.,Ishizuka, T.,Konno, M.,Nagata, T.,Mizuno, Y.,Katayama, K.,Abe-Yoshizumi, R.,Ruhman, S.,Inoue, K.,Kandori, H.,Leon, R.,Shihoya, W.,Yoshizawa, S.,Sheves, M.,Nureki, O.,Beja, O.
Phototrophy by antenna-containing rhodopsin pumps in aquatic environments.
Nature, 615:535-540, 2023

PubMed Abstract: Energy transfer from light-harvesting ketocarotenoids to the light-driven proton pump xanthorhodopsins has been previously demonstrated in two unique cases: an extreme halophilic bacterium and a terrestrial cyanobacterium. Attempts to find carotenoids that bind and transfer energy to abundant rhodopsin proton pumps from marine photoheterotrophs have thus far failed. Here we detected light energy transfer from the widespread hydroxylated carotenoids zeaxanthin and lutein to the retinal moiety of xanthorhodopsins and proteorhodopsins using functional metagenomics combined with chromophore extraction from the environment. The light-harvesting carotenoids transfer up to 42% of the harvested energy in the violet- or blue-light range to the green-light absorbing retinal chromophore. Our data suggest that these antennas may have a substantial effect on rhodopsin phototrophy in the world's lakes, seas and oceans. However, the functional implications of our findings are yet to be discovered.

PubMed: 36859551
DOI: 10.1038/s41586-023-05774-6

Experimental method

ELECTRON MICROSCOPY (2.3 Å)