1E0P

L intermediate of bacteriorhodopsin

Summary for 1E0P

• Entry DOI: 10.2210/pdb1e0p/pdb
• Related: 1AP9 1AT9 1BAC 1BAD 1BCT 1BHA 1BHB 1BM1 1BRD 1BRR 1BRX 1QHJ 1QKO 1QKP 2BRD
• Descriptor: BACTERIORHODOPSIN, GROUND STATE, RETINAL (3 entities in total)
• Functional Keywords: transport, ion transport, photoreceptor, transmembrane, retinal protein hydrogen ion transport
• Biological source: HALOBACTERIUM SALINARIUM
• Cellular location: Cell membrane; Multi-pass membrane protein: P02945
• Total number of polymer chains: 1
• Total formula weight: 25274.97

Authors

Royant, A.,Edman, K.,Ursby, T.,Pebay-Peyroula, E.,Landau, E.M.,Neutze, R. (deposition date: 2000-04-04, release date: 2000-08-19, Last modification date: 2024-11-13)

Primary citation

Royant, A.,Edman, K.,Ursby, T.,Pebay-Peyroula, E.,Landau, E.M.,Neutze, R.
Helix Deformation is Coupled to Vectorial Proton Transport in Bacteriorhodopsin'S Photocycle
Nature, 406:645-, 2000

PubMed Abstract: A wide variety of mechanisms are used to generate a proton-motive potential across cell membranes, a function lying at the heart of bioenergetics. Bacteriorhodopsin, the simplest known proton pump, provides a paradigm for understanding this process. Here we report, at 2.1 A resolution, the structural changes in bacteriorhodopsin immediately preceding the primary proton transfer event in its photocycle. The early structural rearrangements propagate from the protein's core towards the extracellular surface, disrupting the network of hydrogen-bonded water molecules that stabilizes helix C in the ground state. Concomitantly, a bend of this helix enables the negatively charged primary proton acceptor, Asp 85, to approach closer to the positively charged primary proton donor, the Schiff base. The primary proton transfer event would then neutralize these two groups, cancelling their electrostatic attraction and facilitating a relaxation of helix C to a less strained geometry. Reprotonation of the Schiff base by Asp 85 would thereby be impeded, ensuring vectorial proton transport. Structural rearrangements also occur near the protein's surface, aiding proton release to the extracellular medium.

PubMed: 10949307
DOI: 10.1038/35020599

Experimental method

X-RAY DIFFRACTION (2.1 Å)