title: Production and characterization of medium-chain-length polyhydroxyalkanoates by Pseudomonas mosselii TO7.
abstract: The polyhydroxyalkanoate (PHA) production and growth of Pseudomonas mosselii TO7, a newly isolated Pseudomonas species from the wastewater of a vegetable oil manufacturing facility, was analyzed. Phenotypic analysis and phylogenetic analysis of the 16S rRNA gene revealed that it is closely related to Pseudomonas mosselii. In the presence of palm kernel and soybean oils, P. mosselii TO7 produced up to 50% cell dry weight (CDW) medium-chain-length (MCL) PHAs comprising high poly(3-hydroxyoctanoate) (P(3HO)) content; P(3HO) content increased to 45% CDW when grown in octanoate using a single-step culture process. The PHA monomer was identified by (13)C nuclear magnetic resonance spectroscopy. The average molecular weight and polydispersity index of PHA were 218.30 ± 31.73 and 2.21 ± 0.18, respectively. The PHA produced by P. mosselii TO7 in the presence of palm kernel oil had two melting temperature (Tm) values of 37.2°C and 55.7°C with melting enthalpy (ΔHm) values of 51.09 J g(-1) and 26.57 J g(-1), respectively. Inhibition analyses using acrylic and 2-bromooctanoic acids revealed β-oxidation as the primary pathway for MCL-PHA biosynthesis using octanoic acid. Moreover, Pseudomonas putida GPp104 PHA(-), harboring the PHA synthase genes of P. mosselii (phaC1pm and phaC2pm) was used for heterologous expression, which demonstrated that phaC1pm is the main PHA synthesis enzyme, and 3-hydroxyoctanoyl-CoA is its major substrate. This was the first report of a P. mosselii TO7 isolate producing high-yield P(3HO) through utilization of plant oils.
authors.affiliation: Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan; Department of Nursing, Chang Gung University of Science and Technology, Tao-Yuan 33333, Taiwan.
authors.forename: Yi-Jr
authors.initials: YJ
authors.lastname: Chen
authors.affiliation: Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Yan-Chia
authors.initials: YC
authors.lastname: Huang
authors.affiliation: Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan. Electronic address: clee@ntu.edu.tw.
authors.forename: Chia-Yin
authors.initials: CY
authors.lastname: Lee
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002210:Caprylates / Q000378:metabolism; D050356:Lipid Metabolism; D058889:Molecular Typing; D010802:Phylogeny; D010938:Plant Oils / Q000737:chemistry; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis* / Q000737:chemistry; D011549:Pseudomonas / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D044366:Transition Temperature; D062065:Wastewater / Q000382:microbiology; D014871:Water Microbiology
chemical_list: D000217:Acyltransferases; D001426:Bacterial Proteins; D002210:Caprylates; D010938:Plant Oils; D054813:Polyhydroxyalkanoates; D012336:RNA, Ribosomal, 16S; D062065:Wastewater; C101940:3-hydroxyoctanoic acid; C077225:poly(3-hydroxyalkanoic acid) synthase; C031492:octanoic acid
keywords: Carbon/metabolism; Fatty acids; Plant oils; Polyhydroxyalkanoates; Pseudomonas mosselii