Production and characterization of medium-chain-length polyhydroxyalkanoate with high 3-hydroxytetradecanoate monomer content by fadB and fadA knockout mutant of Pseudomonas putida KT2442.
Medium-chain-length polyhydroxyalkanoates (mcl-PHA) consisting of 3-hydroxyhexanoate (HHx), 3-hydroxyoctanoate (HO), 3-hydroxydecanoate, 3-hydroxydodecanoate, and high-content 3-hydroxytetradecanoate (HTD) was produced by knockout mutant Pseudomonas putida KT2442 termed P. putida KTOY06. When grown on 6 to14 g/L single-carbon-source tetradecanoic acid, P. putida KTOY06, which beta-oxidation pathway was weakened by deleting genes of 3-ketoacyl-coenzyme A (CoA) thiolase (fadA) and 3-hydroxyacyl-CoA dehydrogenase (fadB), for the first time, produced several mcl-PHA including 31 to 49 mol% HTD as a major monomer. HHx contents in these mcl-PHAs remained approximately constant at less than 3 mol%. In addition, large amounts of oligo-HTD were detected in cells, indicating the limited ability of P. putida KTOY06 in polymerizing long-chain-length 3-hydroxyalkanoates. The mcl-PHA containing high HTD monomer contents was found to have both higher crystallinity and improved tensile strength compared with that of typical mcl-PHA.
Multidisciplinary Research Center, Shantou University, Shantou 515063, China.
Wenkuan
W
Liu
Guo-Qiang
GQ
Chen
D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D000102:Acetyl-CoA C-Acyltransferase / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001709:Biotechnology / Q000379:methods; D003460:Crystallization; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D009227:Myristic Acids / Q000032:analysis* / Q000378:metabolism; D054813:Polyhydroxyalkanoates / Q000737:chemistry / Q000378:metabolism*; D016958:Pseudomonas putida / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D013718:Tensile Strength
D001426:Bacterial Proteins; D009227:Myristic Acids; D054813:Polyhydroxyalkanoates; C009893:beta-hydroxymyristic acid; D015094:3-Hydroxyacyl CoA Dehydrogenases; D000102:Acetyl-CoA C-Acyltransferase