Photosynthetic carbon metabolism and carboxylating enzymes in Ulva lactuca

Studies in photosynthetic carbon metabolism in the green marine alga, Ulva lactuca were carried out by employing 14CO2. They reveal that it exhibits, HSK pathway of carbon assimilation. The alga belongs to the asparatate former type. Aspartate which is the immediate product of photosynthetic carbon assimilation if further utilised for sucrose synthesis in light but not in dark. In order to confirm the operation of C4 type of photosynthetic pathway, carboxylating enzymes like RuDP and PEP carboxylases were isolated and tested for their activities. The results of these findings are discussed in this paper. (author)