Efficient Production of Fumarate from Maleate Using Recombinant

Abstract:

Fumarate could be produced from maleate with whole cell of recombinant Escherichia coli. However，malate，with a yield of 15.5%，was generated as byproduct by the cellular fumarase，resulting in a decreased fumarate yield and purity. The chromosomal genes，fumA and fumC，in E. coli BL21（DE3） were inactivated，followed by over expression of the maleate cis-trans isomerate. After cultured in a bioreactor，the resulting strain BL21（DE3）△fumA-fumC/pET24a-maiA could generate 64 g/L dry cell weight and maleate cis-trans isomerate of 306 U/mL. With a volumetric ratio of fermentation broth（60 g/L dry cell weight）：fumarate（2 mol/L）=1∶4，fumarate yield of 98.4% and malate yield of 0.7% were produced after incubation at 37 ℃ for 1 h. These results laid a foundation for industrial production of fumarate by whole-cell biocatalyst.