[Photochemical generation of the cation-radical of bacteriochlorophyll b and the anion-radical of bacteriochlorophyll b and bacteriopheophytin b, components of the photosynthesizing bacteria Rhodopseudomonas viridis].

Abstract

The mechanism of photochemical redox reaction of bacteriochlorophyll b, bacteriopheophitin b was studied. The oxidation of bacteriochlorophyll b was carried out in ethanole by means of p-benzoquinone. In ESR spectra the singlet line with delta H = 8.4 gs and g = 2.0025 corresponded to cation-radical. The changes within the region of 400-500 nm, 500-600 nm and the band with the maximum at 685 nm corresponded to cation-radical in the absorption spectra. Photoreduction of bacteriochlorophyll b and bacteriopheophitin b was carried out in triet containing phenilhydrosin. Anion-radicals of bacteriochlorophyll b and bacteriopheophitin b observed in the ESR spectra had singlet form with weak and superthin structure and correspondently with delta H = 10 gs, delta H = 12 gs. The spectrophotometric characteristics of the above pigments were obtained.