1jgj
From Proteopedia
CRYSTAL STRUCTURE OF SENSORY RHODOPSIN II AT 2.4 ANGSTROMS: INSIGHTS INTO COLOR TUNING AND TRANSDUCER INTERACTION
Overview
We report an atomic-resolution structure for a sensory member of the microbial rhodopsin family, the phototaxis receptor sensory rhodopsin II (NpSRII), which mediates blue-light avoidance by the haloarchaeon Natronobacterium pharaonis. The 2.4 angstrom structure reveals features responsible for the 70- to 80-nanometer blue shift of its absorption maximum relative to those of haloarchaeal transport rhodopsins, as well as structural differences due to its sensory, as opposed to transport, function. Multiple factors appear to account for the spectral tuning difference with respect to bacteriorhodopsin: (i) repositioning of the guanidinium group of arginine 72, a residue that interacts with the counterion to the retinylidene protonated Schiff base; (ii) rearrangement of the protein near the retinal ring; and (iii) changes in tilt and slant of the retinal polyene chain. Inspection of the surface topography reveals an exposed polar residue, tyrosine 199, not present in bacteriorhodopsin, in the middle of the membrane bilayer. We propose that this residue interacts with the adjacent helices of the cognate NpSRII transducer NpHtrII.
About this Structure
1JGJ is a Single protein structure of sequence from Natronomonas pharaonis. The following page contains interesting information on the relation of 1JGJ with [Bacteriorhodopsin]. Full crystallographic information is available from OCA.
Reference
Crystal structure of sensory rhodopsin II at 2.4 angstroms: insights into color tuning and transducer interaction., Luecke H, Schobert B, Lanyi JK, Spudich EN, Spudich JL, Science. 2001 Aug 24;293(5534):1499-503. Epub 2001 Jul 12. PMID:11452084 Page seeded by OCA on Fri May 2 21:11:48 2008
