8RSS

Crystal structure of marine actinobacteria clade rhodopsin (MAR) in the O* state

Summary for 8RSS

• Entry DOI: 10.2210/pdb8rss/pdb
• Descriptor: Microbial rhodopsin, OLEIC ACID, EICOSANE, ... (5 entities in total)
• Functional Keywords: mac, macr, mar, proteorhodopsin, pr, xanthorodopsin, xr, membrane protein, xanthorhodopsin
• Biological source: marine Actinobacteria clade; More
• Total number of polymer chains: 1
• Total formula weight: 28516.91

Authors

Bukhdruker, S.,Kovalev, K.,Astashkin, R.,Gordeliy, V. (deposition date: 2024-01-25, release date: 2025-04-02, Last modification date: 2025-04-23)

Primary citation

Bukhdruker, S.,Gushchin, I.,Shevchenko, V.,Kovalev, K.,Polovinkin, V.,Tsybrov, F.,Astashkin, R.,Alekseev, A.,Mikhaylov, A.,Bukhalovich, S.,Bratanov, D.,Ryzhykau, Y.,Kuklina, D.,Caramello, N.,Rokitskaya, T.,Antonenko, Y.,Rulev, M.,Stoev, C.,Zabelskii, D.,Round, E.,Rogachev, A.,Borshchevskiy, V.,Ghai, R.,Bourenkov, G.,Zeghouf, M.,Cherfils, J.,Engelhard, M.,Chizhov, I.,Rodriguez-Valera, F.,Bamberg, E.,Gordeliy, V.
Proteorhodopsin insights into the molecular mechanism of vectorial proton transport.
Sci Adv, 11:eadu5303-eadu5303, 2025

PubMed Abstract: Bacterial proton pumps, proteorhodopsins (PRs), are a major group of light-driven membrane proteins found in marine bacteria. They are functionally and structurally distinct from archaeal and eukaryotic proton pumps. To elucidate the proton transfer mechanism by PRs and understand the differences to nonbacterial pumps on a molecular level, high-resolution structures of PRs' functional states are needed. In this work, we have determined atomic-resolution structures of MAR, a PR from marine actinobacteria, in various functional states, notably the challenging late O intermediate state. These data and information from recent atomic-resolution structures on an archaeal outward proton pump bacteriorhodopsin and bacterial inward proton pump xenorhodopsin allow for deducing key universal elements for light-driven proton pumping. First, long hydrogen-bonded chains characterize proton pathways. Second, short hydrogen bonds allow proton storage and inhibit their backflow. Last, the retinal Schiff base is the active proton donor and acceptor to and from hydrogen-bonded chains.

PubMed: 40238873
DOI: 10.1126/sciadv.adu5303

Experimental method

X-RAY DIFFRACTION (1.41 Å)