Bacteriorhodopsin structures

Janovjak H, Struckmeier J, Hubain M, Kedrov A, Kessler M, Muller DJ (2004) Probing the energy landscape of the membrane protein bacteriorhodopsin Structure 12 871-879... 

Faham, S., and J.U. Bowie (2002) Bicelle crystallization a new method for crystallizing membrane proteins yields a monomeric bacteriorhodopsin structure. J. Mol. Biol. 316, 1-6. 

Hendler, R. W., and Dracheva, S. (2001). Importance of lipids for bacteriorhodopsin structure, photocycle, and function. Biochemistry (Mosc.) 66, 1311-1314. 

Figure 5. Backbone structures of bacteriorhodopsin (left) and Baldwin and Schertler s 1997 rhodopsin model (right) as viewed from the extracellular domain. Helix 1 lies to the bottom right in each case. In the rhodopsin model, helices 4, 6 and 7 are orientated perpendicular to the membrane. Only helix 7 in the bacteriorhodopsin structure is shown perpendicular to the membrane, as it is not possible to orientate helices 4, 6 and 7 perpendicular at the same time, confirming the different tilt of the helices in the two structures.

Fig. 4 A molecular model of the dopamine D2 receptor with a ligand docked in the binding site. The model of the D2 receptor transmembrane helices was constructed from the coordinates of the bacteriorhodopsin structure derived from two-dimensional electron diffraction experiments and is consistent with the projection structure for rhodopsin. The transmembrane helices are represented by a solid ribbon and the drug, apomorphine, is a space filling representation. The top view looking down the helical axis of the receptor clearly delineates the seven transmembrane helices that are the key structural motif for the GPCR superfamily. Some of the helices are inclined relative to the perpendicular to the membrane plane. The bottom view is in the plane of the membrane with the extracellular space at the top of the figure. (Adapted from Ref.t f)...

Hayashi, S., I. Ohmine (2000). Proton transfer in bacteriorhodopsin Structure, excitation, IR spectra, and potential energy surface analyses by an ab initio QM/MM method. Journal of Physical Chemistry B 104(45) 10678-10691. 

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