1H68

sensory rhodopsin II

1H68 の概要

• エントリーDOI: 10.2210/pdb1h68/pdb
• 分子名称: SENSORY RHODOPSIN II, RETINAL, CHLORIDE ION, ... (4 entities in total)
• 機能のキーワード: receptor, archaeal rhodopsin, photoreceptor, phototaxis
• 由来する生物種: NATRONOMONAS PHARAONIS (NATRONOBACTERIUM PHARAONIS)
• 細胞内の位置: Cell membrane; Multi-pass membrane protein: P42196
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 25688.70

構造登録者

Royant, A.,Nollert, P.,Edman, K.,Neutze, R.,Landau, E.M.,Pebay-Peyroula, E.,Navarro, J. (登録日: 2001-06-08, 公開日: 2001-08-28, 最終更新日: 2024-11-06)

主引用文献

Royant, A.,Nollert, P.,Edman, K.,Neutze, R.,Landau, E.M.,Pebay-Peyroula, E.,Navarro, J.
X-Ray Structure of Sensory Rhodopsin II at 2.1 A Resolution
Proc.Natl.Acad.Sci.USA, 98:10131-, 2001

PubMed Abstract: Sensory rhodopsins (SRs) belong to a subfamily of heptahelical transmembrane proteins containing a retinal chromophore. These photoreceptors mediate the cascade of vision in animal eyes and phototaxis in archaebacteria and unicellular flagellated algae. Signal transduction by these photoreceptors occurs by means of transducer proteins. The two archaebacterial sensory rhodopsins SRI and SRII are coupled to the membrane-bound HtrI and HtrII transducer proteins. Activation of these proteins initiates phosphorylation cascades that modulate the flagellar motors, resulting in either attractant (SRI) or repellent (SRII) phototaxis. In addition, transducer-free SRI and SRII were shown to operate as proton pumps, analogous to bacteriorhodopsin. Here, we present the x-ray structure of SRII from Natronobacterium pharaonis (pSRII) at 2.1-A resolution, revealing a unique molecular architecture of the retinal-binding pocket. In particular, the structure of pSRII exhibits a largely unbent conformation of the retinal (as compared with bacteriorhodopsin and halorhodopsin), a hydroxyl group of Thr-204 in the vicinity of the Schiff base, and an outward orientation of the guanidinium group of Arg-72. Furthermore, the structure reveals a putative chloride ion that is coupled to the Schiff base by means of a hydrogen-bond network and a unique, positively charged surface patch for a probable interaction with HtrII. The high-resolution structure of pSRII provides a structural basis to elucidate the mechanisms of phototransduction and color tuning.

PubMed: 11504917
DOI: 10.1073/PNAS.181203898

実験手法

X-RAY DIFFRACTION (2.1 Å)