[Possible role of macromolecular components in the functioning of photosynthetic reaction centers of purple bacteria].

The temperature dependencies of the photoconversion of pigments P870--P890 were studied using isolated chromatophores and photosynthetic reaction centres (RC's) of purple bacteria. The samples were prepared by extraction with organic solvents (light petroleum and a combination of light petroleum and methanol) and modified through cross-linking the functional groups of proteins by treatment with glutaraldehyde or denatured by various physical and chemical treatments. The data provide further evidence that the pool of RC secondary acceptors is formed by the compounds of quinone nature located in the hydrophobic surrounding. Similar molecules localized in a more polar medium act as primary acceptors. The findings indicate on the essential role of macromolecular components in the RC's functioning and also suggest that the photochemical charge separation is conformation-controlled.