Effect of Thiosulfate on the Photosynthetic Growth of Rhodopseudomonas palustris

Autor: James P. Rolls, E. S. Lindstrom
Rok vydání: 1967
Předmět:
Zdroj: Journal of Bacteriology. 94:860-866
ISSN: 1098-5530
0021-9193
DOI: 10.1128/jb.94.4.860-866.1967
Popis: Cell yields of Rhodopseudomonas palustris grown photoheterotrophically in pyruvate-mineral salts medium were increased by the photooxidation of added thiosulfate. However, thiosulfate had no effect on cell yields of cultures grown aerobically in darkness, although thiosulfate was also oxidized. The presence of thiosulfate increased photosynthetic cell yields on a variety of other organic substrates. Growth of cells in thiosulfate-containing medium, or the addition of thiosulfate to cells grown in thiosulfate-free medium, induced the formation of a thiosulfate-oxidizing system which quantitatively photooxidized thiosulfate to sulfate. R. palustris grew photoautotrophically with thiosulfate as an oxidizable substrate. Large amounts of supplemental bicarbonate carbon were incorporated when cells were grown photosynthetically in pyruvate-thiosulfate medium. Cells harvested after photoautotrophic or photoheterotrophic growth in fumarate-thiosulfate medium fixed 14 CO 2 at an 8- to 10-fold greater rate when provided with thiosulfate. The evolution of 14 CO 2 from pyruvate- 1 - 14 C during photoassimilation by R. palustris was greatly suppressed by the presence of thiosulfate. The increase in photoheterotrophic cell yields of R. palustris caused by the oxidation of thiosulfate may result from assimilation of substrate carbon which is normally evolved as carbon dioxide.
Databáze: OpenAIRE