Sodium pyruvate improves the co-production of S-adenosylmethionine and glutathione and its physiological mechanism

In order to investigate the effect of sodium pyruvate on the biosynthesis of S-adenosylmethionine(SAM) and glutathione(GSH),the addition of different concentrations of sodium pyruvate into medium in flasks during different culture time was carried out. It was found that the addition of 2 g/L sodium pyruvate at 0 h was the optimum condition for the biosynthesis of SAM and GSH. The maximum co-production of SAM and GSH of 402.3 mg/L was obtained at 27 h during batch fermentation under the optimum sodium pyruvate addition strategy,which was increased by 35.1% compared to that of the control without sodium pyruvate addition. Moreover,the assay of methionine adenosyltransferase,γ-glutamylcysteine synthase,hexose kinase and isocitrate dehydrogenase,as well as the determination of intracellular NADH and ATP were conducted. It was indicated that the addition of sodium pyruvate increased not only activities of key enzymes involved in SAM and GSH biosynthesis,but also intracellular levels of energy metabolic substance,which in turn improved the capability of SAM and GSH biosynthesis,and the co-production of SAM and GSH. The results presented in this study would provide one feasible approach for efficient production of analogous chemicals biosynthesized with energy consumption.