Evidence for the participation of the reductive pentose phosphate cycle in photoreduction and the oxyhydrogen reaction.

The assimilation of (14)C-sodium bicarbonate has been measured in Scenedesmus obliquus as 1) photosynthesis, 2) photoreduction (light dependent incorporation of carbon dioxide by hydrogen adapted cells under conditions where photosynthesis is inoperative), and 3) the oxyhydrogen reaction (dark assimilation of carbon dioxide by hydrogen adapted cells in an atmosphere of hydrogen and 1% oxygen). Degradation of the glucose formed in each of these reactions using the Leuconostoc technique establishes the participation of the reductive pentose phosphate cycle.