title: Metabolic engineering of Aeromonas hydrophila 4AK4 for production of copolymers of 3-hydroxybutyrate and medium-chain-length 3-hydroxyalkanoate.
abstract: A mutant termed Aeromonas hydrophila AKLF was constructed by deleting acetic acid pathway related genes pta and ackA in A. hydrophila 4AK4. Accumulation of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) in A. hydrophila AKLF was increased by 47% from 2.11 to 3.10g/L associated with a reduction on acetic acid formation compared with A. hydrophila 4AK4 when lauric acid was used as carbon resource. A. hydrophila AKLF harboring pVGAB encoding Vitreoscilla hemoglobin, β-ketothiolase and acetoacetyl-CoA reductase was found to produce 85% more PHBHHx compared to its wild type. Expression of plasmid pD(Ec)L(Pp) harboring genes related to fatty acid metabolism in A. hydrophila AKLF led to 63% more PHBHHx production than A. hydrophila 4AK4. Replacing phaC in A. hydrophila AKLF with a mutant phaC2 from Pseudomonas stutzeri 1317 resulted in enhanced production of copolymers of 3-hydroxybutyrate and medium-chain-length 3-hydroxyalkanoates compared to A. hydrophila 4AK4 harboring the mutant phaC2 in the chromosome as control.
authors.affiliation: Protein Science Laboratory of the Ministry of Education, Department of Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.forename: Jia
authors.initials: J
authors.lastname: Jian
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Shen
authors.forename: Ahleum
authors.initials: A
authors.lastname: Chung
authors.forename: Jinchun
authors.initials: J
authors.lastname: Chen
authors.forename: Guo-Qiang
authors.initials: GQ
authors.lastname: Chen
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000737:chemistry / Q000378:metabolism*; D016980:Aeromonas hydrophila / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids; D011108:Polymers / Q000378:metabolism*
chemical_list: D011108:Polymers; D020155:3-Hydroxybutyric Acid