title: Systematic approach to engineer Escherichia coli pathways for co-utilization of a glucose-xylose mixture.
abstract: Glucose and xylose are two major sugars of lignocellulosic hydrolysate. The regulatory program of catabolite repression in Escherichia coli dictates the preferred utilization of glucose over xylose, which handicaps the development of the lignocellulose-based fermentation process. To co-utilize a glucose-xylose mixture, the E. coli strain was manipulated by pathway engineering in a systematic way. The approach included (1) blocking catabolite repression, (2) enhancing glucose transport, (3) increasing the activity of the pentose phosphate pathway, and (4) eliminating undesirable pathways. Moreover, the ethanol synthetic pathway from Zymomonas mobilis was introduced into the engineered strain. As a consequence, the resulting strain was able to simultaneously metabolize glucose and xylose and consume all sugars (30 g/L each) in 16 h, leading to 97% of the theoretical ethanol yield. Overall, this indicates that this approach is effective and straightforward to engineer E. coli for the desired trait.
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, China Medical University , Taichung, Taiwan 40402.
authors.forename: Chung-Jen
authors.initials: CJ
authors.lastname: Chiang
authors.forename: Hong Min
authors.initials: HM
authors.lastname: Lee
authors.forename: Hong Jhih
authors.initials: HJ
authors.lastname: Guo
authors.forename: Zei Wen
authors.initials: ZW
authors.lastname: Wang
authors.forename: Li-Jen
authors.initials: LJ
authors.lastname: Lin
authors.forename: Yun-Peng
authors.initials: YP
authors.lastname: Chao
mesh_terms: D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D060847:Metabolic Engineering / Q000379:methods*; D053858:Metabolic Networks and Pathways; D014994:Xylose / Q000378:metabolism*
chemical_list: D000431:Ethanol; D014994:Xylose; D005947:Glucose