[Propionate metabolism of Ectothiorhodospira shaposhnikovii during growth in the dark]

Assimilation of propionate by Ectothiorhodospira shaposhnikovii growing under the aerobic conditions in the dark, like in the light involves carboxylation of propionyl-CoA with the participation of biotin-dependent carboxylase. The succinate being formed is transformed in the reactions of the citric acid cycle and the glyoxylate shunt. This is corroborated by the determination of the enzyme activity manifested by cell extracts, by the composition and kinetics of labeled products, as well as by the action of the inhibitors of the citric acid cycle (fluoroacetate, malonate) and avidin on the assimilation of 14C-propionate and 14CO2 by the cells.