title: Constructing a synthetic metabolic pathway in Escherichia coli to produce the enantiomerically pure (R, R)-2,3-butanediol.
abstract: Enantiomerically pure (R, R)-2,3-butanediol has unique applications due to its special chiral group and spatial configuration. Currently, its chemical production route has many limitations. In addition, no native microorganisms can accumulate (R, R)-2,3-butanediol with an enantio-purity over 99%. Herein, we constructed a synthetic metabolic pathway for enantiomerically pure (R, R)-2,3-butanediol biosynthesis in Escherichia coli. The fermentation results suggested that introduction of the synthetic metabolic pathway redistributed the carbon fluxes to the neutral (R, R)-2,3-butanediol, and thus protected the strain against the acetic acid inhibition. Additionally, it showed that the traditionally used isopropyl beta-D-thiogalactoside (IPTG) induction displayed negative effect on (R, R)-2,3-butanediol biosynthesis in the recombinant E. coli, which was probably due to the protein burden. With no IPTG addition, the (R, R)-2,3-butanediol concentration reached 115 g/L by fed-batch culturing of the recombinant E. coli, with an enantio-purity over 99%, which is suitable for the pilot-scale production.
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing, 211816, People's Republic of China. xiaojunji@njtech.edu.cn.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Ji
authors.forename: Lu-Gang
authors.initials: LG
authors.lastname: Liu
authors.forename: Meng-Qiu
authors.initials: MQ
authors.lastname: Shen
authors.forename: Zhi-Kui
authors.initials: ZK
authors.lastname: Nie
authors.forename: Ying-Jia
authors.initials: YJ
authors.lastname: Tong
authors.forename: He
authors.initials: H
authors.lastname: Huang
mesh_terms: D061249:Batch Cell Culture Techniques / Q000379:methods; D002072:Butylene Glycols / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005285:Fermentation; D007218:Industrial Microbiology / Q000379:methods; D007544:Isopropyl Thiogalactoside / Q000378:metabolism; D060847:Metabolic Engineering / Q000379:methods*; D053858:Metabolic Networks and Pathways
chemical_list: D002072:Butylene Glycols; D007544:Isopropyl Thiogalactoside; C026978:2,3-butylene glycol
keywords: (R, R)-2,3-butanediol; Escherichia coli; acetic acid; metabolic engineering