title: Overexpressions of xylA and xylB in Klebsiella pneumoniae Lead to Enhanced 1,3-Propanediol Production by Cofermentation of Glycerol and Xylose.
abstract: 1,3-Propanediol (1,3-PD) is a valuable platform compound. Many studies have shown that the supplement of NADH plays a key role in the bioproduction of 1,3-PD from Klebsiella pneumoniae. In this study, the xylA and xylB genes from Escherichia coli were overexpressed individually or simultaneously in K. pneumoniae to improve the production of 1,3-PD by cofermentation of glycerol and xylose. Compared with the parent strain, the xylose consumption was significantly increased by the introduction of these two genes. The 1,3-PD titers were raised from 17.9 g/l to 23.5, 23.9, and 24.4 g/l, respectively, by the overexpression of xylA and xylB as well as their coexpression. The glycerol conversion rate (mol/mol) was enhanced from 54.1% to 73.8%. The concentration of 2,3-butanediol was increased by 50% at the middle stage but drastically decreased after that. The NADH and NADH/NAD(+) ratio were improved. This report suggests that overexpression of xylA or xylB is an effective strategy to improve the xylose assimilation rate to provide abundant reducing power for the biosynthesis of 1,3-PD in K. pneumoniae.
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, P.R. China.
authors.forename: Xinyao
authors.initials: X
authors.lastname: Lu
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, P.R. China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Fu
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, P.R. China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zong
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, P.R. China.|The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, P.R. China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhuge
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D005285:Fermentation; D015870:Gene Expression; D005990:Glycerol / Q000378:metabolism*; D007711:Klebsiella pneumoniae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D011409:Propylene Glycols / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D011409:Propylene Glycols; C041787:1,3-propanediol; D014994:Xylose; D005990:Glycerol
keywords: 1,3-Propanediol; Klebsiella pneumoniae; xylA; xylB; xylose