X-Ray Diffraction Analysis of Three-Dimensional Crystals of Bovine Rhodopsin Obtained from Mixed Micelles

摘要: Rhodopsin, a prototypic G protein-coupled receptor responsible for absorption of photons in retinal rod photoreceptor cells, was selectively extracted from bovine outer segment membranes, employing mixed micelles nonyl beta-d-glucoside and heptanetriol. Highly purified rhodopsin crystallized solutions containing varying amounts detergent amphiphile. The crystals contained ground state molecules as judged by their red color the linear dichroism originating 11-cis-retinal chromophore. However, when exposed to visible light, even at 4 degrees C, bleached decomposed. Reflections diffraction pattern were observed out 3.5-A resolution 100 K most ordered crystals. Diffraction data have been processed 3.85-A resolution. symmetry systematic absences indicate that tetragonal symmetry, space group P4(1)22 or P4(3)22, = b 96.51 A, c 148.55 A. A value 4.12 A(3)/Da V(M) obtained one monomer asymmetric unit (eight per cell). Our study is first characterization three-dimensional crystal may be valuable future structural studies on related receptors this important superfamily.