title: [Construction of polyhydroxybutyrate pathway in Klebsiella pneumoniae].
abstract: 1,3-propanediol production with the byproduct of biodiesel production is important to increase the economic benefit of biodiesel industry. Accumulation of 3-hydroxypropionaldehyde is one of the key problems in the 1,3-propanediol fermentation process, leading to the cell death and the fermentation abnormal ceasing. Different from the traditional way of reducing the accumulation of the 3-hydroxypropionaldehyde, we introduced the polyhydroxybutyrate pathway into the Klebsiella pneumoniae for the first time to enhance the tolerance of K. pneumoniae to 3-hydroxypropionaldehyde, at the same time, to improve the 1,3-propanediol production. Plasmid pDK containing phbC, phbA, phbB gene was constructed and transformed into K. pneumoniae successfully. PHB was detected in the engineered K. pneumoniae after IPTG induction and its content enhanced with the IPTG concentration increasing. The optimized IPTG concentration was 0.5 mmol/L. The constructed K. pneumoniae could produce 1,3-propanediol normally, at the same time accumulate polyhydroxybutyrate. With the constructed strain, the fermentation proceeds normally with the initial glucose was 70 g/L which the wild type strain stopped growing and the fermentation was ceasing; 1,3-propanediol concentration and yield reached 31.3 g/L and 43.9% at 72 h. Our work is helpful for the deep understanding of 1,3-propanediol metabolic mechanism of Klebsiella pneumoniae, and also provides a new way for strain optimization of Klebsiella pneumoniae.
authors.affiliation: College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Guo
authors.affiliation: Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China.
authors.forename: Hongjuan
authors.initials: H
authors.lastname: Liu
authors.affiliation: College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China.
authors.forename: Jian'an
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Dehua
authors.initials: D
authors.lastname: Liu
mesh_terms: D005818:Genetic Engineering / Q000379:methods; D006885:Hydroxybutyrates / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism; D011409:Propylene Glycols / Q000378:metabolism*
chemical_list: D006885:Hydroxybutyrates; D011108:Polymers; D011409:Propylene Glycols; C041787:1,3-propanediol