Production of succinic acid from sucrose and sugarcane molasses by metabolically engineered Escherichia coli

Abstract

Sucrose-utilizing genes (cscKB and cscA) from Escherichia coli KO11 were cloned and expressed in a metabolically engineered E. coli KJ122 to enhance succinate production from sucrose. KJ122 harboring a recombinant plasmid, pKJSUC, was screened for the efficient sucrose utilization by growth-based selection and adaptation. KJ122-pKJSUC-24T efficiently utilized sucrose in a low-cost medium to produce high succinate concentration with less accumulation of by-products. Succinate concentrations of 51g/L (productivity equal to 1.05g/L/h) were produced from sucrose in anaerobic bottles, and concentrations of 47g/L were produced in 10L bioreactor within 48h. Antibiotics had no effect on the succinate production by KJ122-pKJSUC-24T. In addition, succinate concentrations of 62g/L were produced from sugarcane molasses in anaerobic bottles, and concentrations of 56g/L in 10L bioreactor within 72h. These results demonstrated that KJ122-pKJSUC-24T would be a potential strain for bio-based succinate production from sucrose and sugarcane molasses.