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Publication Abstract from PubMed
Halorhodopsin, an archaeal rhodopsin ubiquitous in Haloarchaea, uses light energy to pump chloride through biological membranes. Halorhodopsin crystals were grown in a cubic lipidic phase, which allowed the x-ray structure determination of this anion pump at 1.8 angstrom resolution. Halorhodopsin assembles to trimers around a central patch consisting of palmitic acid. Next to the protonated Schiff base between Lys(242) and the isomerizable retinal chromophore, a single chloride ion occupies the transport site. Energetic calculations on chloride binding reveal a combination of ion-ion and ion-dipole interactions for stabilizing the anion 18 angstroms below the membrane surface. Ion dragging across the protonated Schiff base explains why chloride and proton translocation modes are mechanistically equivalent in archaeal rhodopsins.
Structure of the light-driven chloride pump halorhodopsin at 1.8 A resolution.,Kolbe M, Besir H, Essen LO, Oesterhelt D Science. 2000 May 26;288(5470):1390-6. PMID:10827943[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Kolbe M, Besir H, Essen LO, Oesterhelt D. Structure of the light-driven chloride pump halorhodopsin at 1.8 A resolution. Science. 2000 May 26;288(5470):1390-6. PMID:10827943
