Calvin-Benson cycle carbonic acid

Purple sulfur bacteria fix carbon dioxide using the Calvin-Benson cycle, but green sulfur bacteria use a completely different pathway, the reverse tricarboxylic acid cycle. Other photosynthetic bacteria use still different pathways for CO2 fixation (Perry and Staley, 1997). 

Although some plants, such as those called C4 and those known as using Crassulacean acid metabolism (CAM) photosynthesis (i.e., xerophytes) initially capture the carbon dioxide (CO2) differently than the C3 plants do, they too subsequently release it to the Calvin cycle (M. Calvin [1911-1997], professor. University of California, Berkeley, since 1937, Nobel Prize in Chemistry 1961 Bassham, I Benson, A. Calvin, M. [1950]./ Biol. C/iem., 1950,7S5,781). 

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