Modification of CO₂ fixation of photosynthetic prokaryote

Summary

Resemblances and differences on photosynthesis of C₃ plant and cyanobacterium Synechococcus PCC7942 were discussed with a simplified model of photosynthesis and photorespiration. Then the transformation of the cyanobacterium was shown with Chromatium vinosum (Cv) RuBisCO. Total RuBisCO activity and photosynthesis were compared with wild type S. 7942 and RuBisCO high expression mutant. Results were explained with RuBisCO environment of S. 7942 mutant. For excluding the influence of inorganic carbon concentrating mechanism (CCM) on the effect of RuBisCO, carboxysome less mutant was created with homologous recombination of ccm operon to be replaced with kanamycine resistant gene. And the deletion of the operon was confirmed by genomic PCR on the transformant. The confirmation was performed with three primers. Electron micrograms of S. 7942 show the existence of carboxysome in wild type and its absence in the mutant. Growth rate of CL mutant on different CO₂ concentration shows that there is a possibility to increase a photosynthetic ability of a cyanobacterium with increases the RuBisCO activity.