Tianjin Institute of industrial biology has made important progress in the production of succinic acid from glycerol

Succinic acid can be used in the synthesis of 1,4-butanediol, tetrahydrofuran, γ - butyrolactone and PBS degradable plastics It has a wide range of uses in the fields of chemical industry, materials, medicine and food It is listed as one of the 12 most valuable platform compounds in the future by the U.S Department of energy In recent years, it has become a research hotspot in the world to build a microbial cell factory that can produce succinic acid efficiently and convert renewable biomass resources into Succinic Acid efficiently Glycerol, as a carbon source with high reduction force, has a great advantage in the production of succinic acid and other products requiring more reduction force However, the production of succinic acid with glycerol as substrate is still challenging in metabolic engineering transformation microorganisms, and the yield and production rate of succinic acid under anaerobic conditions are very low The team of microbial metabolism engineering led by researcher Zhang Xueli of Tianjin Institute of industrial biotechnology, Chinese Academy of Sciences, through the rational analysis of the pathway of anaerobic glycerol metabolism, speculated that the two original pathways of glycerol anaerobic metabolism of E Through gene editing, the team inactivated the two original glycerol metabolism pathways in E.coli, and replaced the original PEP dependent dihydroxyacetone kinase in E.coli with ATP dependent dihydroxyacetone kinase from Klebsiella, thus building a new anaerobic glycerol metabolism pathway in E.coli The new glycerol metabolic pathway not only does not consume PEP for dihydroxyacetone phosphorylation, but also generates additional proton dynamic potential to provide energy for cell growth and succinic acid efflux The yield, specific production rate and intracellular ATP content of succinic acid increased by 282%, 63% and 338% respectively Under anaerobic conditions, 483 mm succinic acid can be produced within 96 hours, and the conversion rate is 92% of the theoretical maximum conversion rate The specific production rate is the highest level so far This study shows that energy supply is the key regulatory factor in the production of succinic acid by glycerol anaerobic fermentation, and the synthesis efficiency of succinic acid can be significantly improved by increasing energy supply through the generation of proton dynamic potential This study laid a technical foundation for the production of succinic acid with glycerol as raw material The research was supported by the national key research and development program of synthetic biology and NSFC The related research results were published on metabolic engineering (DOI: 10.1016 / j.ymben 2019.10.002) The doctoral research of Tianjin Institute of technology, Chinese Academy of Sciences was born in Yong as the first author of the paper, and researcher Zhang Xueli was the corresponding author of the paper