3NSB

Structure of bacteriorhodopsin ground state before and after X-ray modification

3NSB の概要

• エントリーDOI: 10.2210/pdb3nsb/pdb
• 関連するPDBエントリー: 3NS0
• 分子名称: Bacteriorhodopsin, RETINAL, 1-[2,6,10.14-TETRAMETHYL-HEXADECAN-16-YL]-2-[2,10,14-TRIMETHYLHEXADECAN-16-YL]GLYCEROL, ... (4 entities in total)
• 機能のキーワード: ion pump, membrane protein, retinal protein, photoreceptor, merohedral twinning, radiation damage, 7-helix transmembrane, ion transport, membrane
• 由来する生物種: Halobacterium salinarum (Halobacterium halobium)
• 細胞内の位置: Cell membrane; Multi-pass membrane protein: P02945
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 32851.02

構造登録者

Borshchevskiy, V.I. (登録日: 2010-07-01, 公開日: 2011-05-11, 最終更新日: 2024-11-20)

主引用文献

Borshchevskiy, V.I.,Round, E.S.,Popov, A.N.,Buldt, G.,Gordeliy, V.I.
X-ray-Radiation-Induced Changes in Bacteriorhodopsin Structure.
J.Mol.Biol., 409:813-825, 2011

PubMed Abstract: Bacteriorhodopsin (bR) provides light-driven vectorial proton transport across a cell membrane. Creation of electrochemical potential at the membrane is a universal step in energy transformation in a cell. Published atomic crystallographic models of early intermediate states of bR show a significant difference between them, and conclusions about pumping mechanisms have been contradictory. Here, we present a quantitative high-resolution crystallographic study of conformational changes in bR induced by X-ray absorption. It is shown that X-ray doses that are usually accumulated during data collection for intermediate-state studies are sufficient to significantly alter the structure of the protein. X-ray-induced changes occur primarily in the active site of bR. Structural modeling showed that X-ray absorption triggers retinal isomerization accompanied by the disappearance of electron densities corresponding to the water molecule W402 bound to the Schiff base. It is demonstrated that these and other X-ray-induced changes may mimic functional conformational changes of bR leading to misinterpretation of the earlier obtained X-ray crystallographic structures of photointermediates.

PubMed: 21530535
DOI: 10.1016/j.jmb.2011.04.038

実験手法

X-RAY DIFFRACTION (1.78 Å)