Metabolic engineering of Escherichia coli for production of butyric acid.
The butyrate production by engineered Escherichia coli is afflicted by both low titer and low selectivity (defined as the butyrate/acetate (B/A) ratio). To address this issue, a strategy for metabolic engineering of E. coli was implemented including (1) elimination of all major NADH-dependent reactions in the fermentation metabolism, (2) reconstruction of a heterologous pathway leading to butyryl-CoA, (3) recruitment of endogenous atoDA for conversion of butyryl-CoA to butyrate with acetate as a CoA acceptor, and (4) removal of the acetate-synthesis pathway. Grown on glucose (20 g/L) plus acetate (8 g/L), the engineered strain consumed almost all glucose and acetate and produced 10 g/L butyrate as a predominant product within 48 h. It leads to high butyrate selectivity with the B/A ratio reaching 143. The result shows that our proposed approach may open a new avenue in biotechnology for production of butyrate in E. coli.
Department of Chemical Engineering, Feng Chia University 100 Wenhwa Road, Taichung 40724, Taiwan.
Mukesh
M
Saini
Zei Wen
ZW
Wang
Chung-Jen
CJ
Chiang
Yun-Peng
YP
Chao
D000085:Acetates / Q000378:metabolism; D053898:Biosynthetic Pathways; D002087:Butyrates / Q000378:metabolism; D020148:Butyric Acid / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D060847:Metabolic Engineering
D000085:Acetates; D002087:Butyrates; D029968:Escherichia coli Proteins; D020148:Butyric Acid; D005947:Glucose