6GAC

BACTERIORHODOPSIN, 490 FS STATE, REAL-SPACE REFINED AGAINST 15% EXTRAPOLATED STRUCTURE FACTORS

Summary for 6GAC

• Entry DOI: 10.2210/pdb6gac/pdb
• Descriptor: Bacteriorhodopsin, nonane, TETRADECANE, ... (12 entities in total)
• Functional Keywords: membrane protein, proton pump, time-resolved crystallography, free-electron laser
• Biological source: Halobacterium salinarum (strain ATCC 700922 / JCM 11081 / NRC-1) (Halobacterium halobium)
• Total number of polymer chains: 1
• Total formula weight: 30794.61

Authors

Nass Kovacs, G.,Colletier, J.-P.,Gruenbein, M.L.,Stensitzki, T.,Batyuk, A.,Carbajo, S.,Doak, R.B.,Ehrenberg, D.,Foucar, L.,Gasper, R.,Gorel, A.,Hilpert, M.,Kloos, M.,Koglin, J.,Reinstein, J.,Roome, C.M.,Schlesinger, R.,Seaberg, M.,Shoeman, R.L.,Stricker, M.,Boutet, S.,Haacke, S.,Heberle, J.,Domratcheva, T.,Schlichting, I. (deposition date: 2018-04-11, release date: 2019-04-24, Last modification date: 2024-11-06)

Primary citation

Nass Kovacs, G.,Colletier, J.P.,Grunbein, M.L.,Yang, Y.,Stensitzki, T.,Batyuk, A.,Carbajo, S.,Doak, R.B.,Ehrenberg, D.,Foucar, L.,Gasper, R.,Gorel, A.,Hilpert, M.,Kloos, M.,Koglin, J.E.,Reinstein, J.,Roome, C.M.,Schlesinger, R.,Seaberg, M.,Shoeman, R.L.,Stricker, M.,Boutet, S.,Haacke, S.,Heberle, J.,Heyne, K.,Domratcheva, T.,Barends, T.R.M.,Schlichting, I.
Three-dimensional view of ultrafast dynamics in photoexcited bacteriorhodopsin.
Nat Commun, 10:3177-3177, 2019

PubMed Abstract: Bacteriorhodopsin (bR) is a light-driven proton pump. The primary photochemical event upon light absorption is isomerization of the retinal chromophore. Here we used time-resolved crystallography at an X-ray free-electron laser to follow the structural changes in multiphoton-excited bR from 250 femtoseconds to 10 picoseconds. Quantum chemistry and ultrafast spectroscopy were used to identify a sequential two-photon absorption process, leading to excitation of a tryptophan residue flanking the retinal chromophore, as a first manifestation of multiphoton effects. We resolve distinct stages in the structural dynamics of the all-trans retinal in photoexcited bR to a highly twisted 13-cis conformation. Other active site sub-picosecond rearrangements include correlated vibrational motions of the electronically excited retinal chromophore, the surrounding amino acids and water molecules as well as their hydrogen bonding network. These results show that this extended photo-active network forms an electronically and vibrationally coupled system in bR, and most likely in all retinal proteins.

PubMed: 31320619
DOI: 10.1038/s41467-019-10758-0

Experimental method

X-RAY DIFFRACTION (1.8 Å)