Chen Yi-Jr, Huang Yan-Chia, Lee Chia-Yin
Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan; Department of Nursing, Chang Gung University of Science and Technology, Tao-Yuan 33333, Taiwan.
Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan.
J Biosci Bioeng. 2014 Aug;118(2):145-52. doi: 10.1016/j.jbiosc.2014.01.012. Epub 2014 Mar 12.
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.
对从植物油生产设施废水中新分离出的假单胞菌属苔藓假单胞菌TO7的聚羟基脂肪酸酯（PHA）产量和生长情况进行了分析。对16S rRNA基因的表型分析和系统发育分析表明，它与苔藓假单胞菌密切相关。在棕榈仁油和大豆油存在的情况下，苔藓假单胞菌TO7产生高达50%细胞干重（CDW）的中链长度（MCL）PHA，其中聚（3-羟基辛酸酯）（P(3HO)）含量较高；在辛酸中采用一步培养法生长时，P(3HO)含量增加到45% CDW。通过（13）C核磁共振光谱法鉴定了PHA单体。PHA的平均分子量和多分散指数分别为218.30±31.73和2.21±0.18。苔藓假单胞菌TO7在棕榈仁油存在下产生的PHA有两个熔点（Tm）值，分别为37.2°C和55.7°C，熔化焓（ΔHm）值分别为51.09 J g(-1)和26.57 J g(-1)。使用丙烯酸和2-溴辛酸进行的抑制分析表明，β-氧化是使用辛酸进行MCL-PHA生物合成的主要途径。此外，携带苔藓假单胞菌PHA合酶基因（phaC1pm和phaC2pm）的恶臭假单胞菌GPp104 PHA(-)用于异源表达，这表明phaC1pm是主要的PHA合成酶，3-羟基辛酰辅酶A是其主要底物。这是关于苔藓假单胞菌TO7分离株通过利用植物油高产P(3HO)的首次报道。
