[Thiosulfate oxidation by nonsulfur purple bacteria].

The capability to oxidize thiosulfate was studied in 11 cultures of purple bacteria belonging to Rhodomicrobium vannielii, Rhodopseudmonas viridis, Rh. sphaeroides, Rh. capsulata, and Rhodospirillum rubrum.

[Thiosulfate metabolism in Rhodopseudomonas palustris].

The cells of the purple nonsulfur bacterium Rhodopseudomonas palustris, Nakamura strain, are capable of oxidizing thiosulfate and sulfide both under the anaerobic conditions in the light and under the aerobic conditions in the dark. Regardless of the presence of thiosulfate in the medium, the cells contain thiosulfate reductase, rodanase, thiosulfate oxidase, and sulfite oxidase. However, the capability to oxidize thiosulfate and sulfide is induced in Rh.

[Carbonic anhydrase activity of phototropic bacteria].

The activity of carboanhydrase was assayed in seven species of phototrophous bacteria: three species of the Rhodospirillaceae genus, three species of the Chromatiaceae genus, and one species of the Chlorobiaceae genus. The activity of carboanhydrase was found in five species among seven. It decreased on passing from photoautotrophous to photoheterotrophous conditions of growth, and then to dark heterotrophous conditions, which correlated with the activity of the Calvin cycle in the bacteria.

[Oxidative phosphorylation capacity of Rhodopseudomonas palustris during growth in light and darkness].

Assimilation of oxygen by the cells of Rhodopseudomonas palustris grown in the light and in the darkness is stimulated by p-chlorocarbonylcyanidephanylhydrazone, suggesting respiration coupled to phosphorylatin. Membranes of the cells grown in the light are capable of oxidative phosphorylation in the course of electron transport from NADH and succinate to O2 with P/O being 0.03 and 0.

[Composition and content of cytochromes in Rhodopseudomonas palustris in relation to growth conditions].

Differential spectra, CO spectra and spectra of hemochromes were studied in the cells of Rhodopseudomonas palustris grown in aerobic conditions in the light and in the darkness; the terminal oxidase was cytochrome a. This cytochrome was not detected in the cells cultivated in anaerobic conditions in the light. The content of cytochromes b was higher in the cells grown in aerobic conditions in the darkness; the content of cytochromes c was higher in the cells cultivated in anaerobic conditions in the light.