Abstract
The quantum efficiency of photosynthesis by the green sulfur bacterium, Chlorobium thiosulfatophilum, has been determined in systems in which thiosulfate, tetrathionate, and molecular hydrogen served as electron donors. It was found that about 10 ± 1 quanta are used for the assimilation of 1 molecule of CO2, and that the quantum number is independent of the nature of the electron donor. These results are considered as support for the view that also in the bacterial photosyntheses the primary photochemical reaction consists in the photolysis of H2O, and that the chemical energy released during the oxidation of the electron donor is not utilized for CO2 assimilation. Hence the photosynthetic processes of the green sulfur bacteria are thermodynamically less efficient than is green plant photosynthesis.
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Selected References
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- FRENKEL A., GAFFRON H., BATTLEY E. H. Photosynthesis and photoreduction by the blue green alga, Synechococcus elongatus, Näg. Biol Bull. 1950 Oct;99(2):157–162. doi: 10.2307/1538735. [DOI] [PubMed] [Google Scholar]
- LARSEN H. On the culture and general physiology of the green sulfur bacteria. J Bacteriol. 1952 Aug;64(2):187–196. doi: 10.1128/jb.64.2.187-196.1952. [DOI] [PMC free article] [PubMed] [Google Scholar]
- VAN NIEL C. B. The comparative biochemistry of photosynthesis. Am Sci. 1949 Jul;37(3):371–383. [PubMed] [Google Scholar]