text: Propionyl-CoA accumulation can prove toxic to different organisms. Since different cycles have been proposed regarding how propionyl-CoA is transformed into pyruvate, one studied mechanism is the methylcitrate cycle. The initial reaction is beta-oxidation to form the propionyl-CoA which is further broken down by the cycle. This pathway involves the enzymes both related to the methylcitrate cycle as well as the citric acid cycle. These all contribute to the overall reaction to detoxify the bacteria from harmful propionyl-CoA. It is also attributed as a resulting pathway due to the catabolism of fatty acids in mycobacteria. In order to proceed, the prpC gene codes for methylcitrate synthase, and if not present, the methylcitrate cycle will not occur. Instead, catabolism proceeds through propionyl-CoA carboxylase. This mechanism is shown below to the left along with the participating reactants, products, intermediates, and enzymes.