Analyses of key enzyme activities related in producing succinic acid in Mannheimia Succiniciproducens MBEL55E

Abstract

Mannheimia succiniciproducens MBEL55E, a capnophilic rumen bacterium, produces succinic acid in high concentrations as a fermentation end product under anaerobic conditions. M. succiniciproducens uses anaplerotic pathway to produce succinic acid. In the beginning of the anaplerotic pathway, two Enzymes, phosphoenolpyruvate carboxylase(Ppc) and phosphoenolpyruvate kinase(PckA), take part in the reaction. They convert phosphoenolpyruvate to oxaloacetate. We analysed activation of both enzymes to elucidate the roles in the production of succinic acid. We can find that PckA is much stronger than Ppc in M.succiniciproducens, suggesting that PckA is a very important enzyme for producing succinic acid.