<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Volkov, V. V.</style></author><author><style face="normal" font="default" size="100%">Svirko, Y P</style></author><author><style face="normal" font="default" size="100%">Kamalov, Valey F.</style></author><author><style face="normal" font="default" size="100%">Song, Li</style></author><author><style face="normal" font="default" size="100%">El-Sayed, Mostafa A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Optical rotation of the second harmonic radiation from retinal in bacteriorhodopsin monomers in Langmuir-Blodgett film: evidence for nonplanar retinal structure.</style></title><secondary-title><style face="normal" font="default" size="100%">Biophysical journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biophys. J.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Bacteriorhodopsins</style></keyword><keyword><style  face="normal" font="default" size="100%">Biophysical Phenomena</style></keyword><keyword><style  face="normal" font="default" size="100%">Biophysics</style></keyword><keyword><style  face="normal" font="default" size="100%">Circular Dichroism</style></keyword><keyword><style  face="normal" font="default" size="100%">Molecular Structure</style></keyword><keyword><style  face="normal" font="default" size="100%">Optics and Photonics</style></keyword><keyword><style  face="normal" font="default" size="100%">Retinaldehyde</style></keyword><keyword><style  face="normal" font="default" size="100%">Spectrophotometry</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1997</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1997 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">3164-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We observed optical rotation of the plane of polarization of the second harmonic (SH) radiation at 532 nm (in resonance with the retinal absorption) generated in reflection geometry in Langmuir-Blodgett film of bacteriorhodopsin (bR). The analysis of the experimental data showed that this effect arises from the nonvanishing contribution of the antisymmetrical part of the hyperpolarizability tensor. This requires that the dipole moment of the resonant electronic transition, the change of the dipole moment upon electronic excitation, and the long axis of the retinal not be coplanar. Such conditions are satisfied only if the retinal has a nonplanar geometry, a conclusion that could lend support to the heterogeneity model of the origin of the biphasic band shape of the linear CD spectrum of the retinal in bR. On the basis of our theoretical analysis, we were able to estimate the angle between the induced dipole moment and the plan that contains the long axis of the chromophore and the transition dipole moment of the retinal absorption.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/9414228?dopt=Abstract</style></custom1><electronic-resource-num><style face="normal" font="default" size="100%">10.1016/S0006-3495(97)78342-5</style></electronic-resource-num></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Song, Li</style></author><author><style face="normal" font="default" size="100%">Logunov, Stephan L.</style></author><author><style face="normal" font="default" size="100%">Yang, Difei</style></author><author><style face="normal" font="default" size="100%">El-Sayed, Mostafa A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The pH dependence of the subpicosecond retinal photoisomerization process in bacteriorhodopsin: evidence for parallel photocycles.</style></title><secondary-title><style face="normal" font="default" size="100%">Biophysical journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biophys. J.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Bacteriorhodopsins</style></keyword><keyword><style  face="normal" font="default" size="100%">Biophysical Phenomena</style></keyword><keyword><style  face="normal" font="default" size="100%">Biophysics</style></keyword><keyword><style  face="normal" font="default" size="100%">Hydrogen-Ion Concentration</style></keyword><keyword><style  face="normal" font="default" size="100%">Isomerism</style></keyword><keyword><style  face="normal" font="default" size="100%">Kinetics</style></keyword><keyword><style  face="normal" font="default" size="100%">Molecular Structure</style></keyword><keyword><style  face="normal" font="default" size="100%">Photochemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Retinaldehyde</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1994</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1994 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">67</style></volume><pages><style face="normal" font="default" size="100%">2008-12</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The pH dependence of the subpicosecond decay of the retinal photoexcited state in bacteriorhodopsin (bR) is determined in the pH range 6.8-11.3. A rapid change in the decay rate of the retinal photoexcited state is observed in the pH range 9-10, the same pH range in which a rapid change in the M412 formation kinetics was observed. This observation supports the previously proposed heterogeneity model in which parallel photocycles contribute to the observed pH dependence of the M412 formation kinetics in bR.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/7858138?dopt=Abstract</style></custom1><electronic-resource-num><style face="normal" font="default" size="100%">10.1016/S0006-3495(94)80684-8</style></electronic-resource-num></record></records></xml>