Spectroscopic characterization of bacteriorhodopsin's L-intermediate in 3D crystals cooled to 170 K.
Spectra are presented from a single 3D microcrystal of bacteriorhodopsin (bR) cooled to 170 K under various illumination conditions. This set is necessary and sufficient to assign the relevant crystal reference spectra. A spectral decomposition of the difference spectrum obtained following the trapping protocol of Royant et al. (2000) (Nature 406, 645-648) is given, confirming that the low temperature L-intermediate was the species that dominated the structural rearrangements previously reported. Smaller contributions from the K and M spectral intermediates are also quantified. Mechanistic insights derived from the X-ray structures of the early bR intermediates are discussed.
Royant
A
A
Institut de Biologie Structurale, UMR 5075-CEA-CNRS-Université Joseph Fourier, Grenoble, France.
Edman
K
K
Ursby
T
T
Pebay-Peyroula
E
E
Landau
E M
EM
Neutze
R
R
D001436:Bacteriorhodopsins / Q000737:chemistry* / Q000528:radiation effects; D003080:Cold Temperature; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D010777:Photochemistry; D013053:Spectrophotometry; D055672:Static Electricity
D001436:Bacteriorhodopsins