X-ray crystallographic analysis of 9-cis-rhodopsin, a model analogue visual pigment

Photochem Photobiol. 2007 Mar-Apr;83(2):232-5. doi: 10.1562/2006-13-RA-920.

Abstract

Recent progress in high-resolution structural study of rhodopsin has been enabled by a novel selective extraction procedure with rod photoreceptor cells. In this study, we applied the method for rapid and efficient preparation of a purified analogue pigment using bovine rod outer segment membranes with 9-cis-retinal. After complete bleaching of the membranes and subsequent regeneration with the exogenous retinal, 9-cis-rhodopsin is selectively extracted from the membranes using combination of zinc and heptylthioglucoside. The solubilized sample, even with a small amount of contaminating retinal oximes, is shown to be pure enough for three-dimensional crystallization. The X-ray diffraction from 9-cis-rhodopsin crystals was examined and the electron density map at 2.9 angstroms resolution in the chromophore region can be fitted well with the model of 9-cis-retinal Schiff base.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Crystallography, X-Ray
  • Models, Molecular
  • Photochemistry
  • Rhodopsin / chemistry*
  • Rhodopsin / isolation & purification
  • Rod Cell Outer Segment / chemistry
  • Spectrophotometry
  • Static Electricity

Substances

  • Rhodopsin