[Slow photoinduced changes in reaction centers of Rhodobacter sphaeroides R-26 by holographic interferometry].

Using the on-line holographic interferometry, changes in the refraction index of illuminated solutions containing the Rhodobacter sphaeroides R-26 reaction centers isolated from membranes by detergents of ionic and nonionic nature were registered. Factors affecting the refraction index of these solutions were analyzed. It was shown that the photoinduced changes in this parameter are due to structural changes in the molecular complex of reaction centers. The results of measurements of the kinetics of absorption spectra at lambda = 865 nm for two detergent types are presented, which coincide qualitatively with the results of holographic measurements. The change in the volume of the molecular complex of reaction centers was estimated to be 0.1 divided by 1%.