| Title | Biosynthesis of Copolyesters Consisting of 3-Hydroxyvalerate and Medium-chain-length 3-hydroxyalkanoates by the Pseudomonas aeruginosa P-5 Strain | ||
| Author | Sang Hee Woo, Jae Hee Kim, Yu-Yang Ni, and Young Ha Rhee* | ||
| Address | Department of Microbiology and Molecular Biology, Chungnam National University | ||
| Bibliography | Korean Journal of Microbiology, 48(3),200-206, 2012 | ||
| DOI | |||
| Key Words | Pseudomonas aeruginosa, 3-hydroxyvalerate, MCL-PHA synthase, polyhydroxyalkanoate | ||
| Abstract | A bacterial strain capable of synthesizing polyhydroxyalkanoates (PHAs) with an unusual pattern of monomer units was isolated from activated sludge using the enrichment culture technique. The organism, identified as Pseudomonas aeruginosa P-5, produced polyesters consisting of 3-hydroxyvalerate and medium-chain-length (MCL) 3-hydroxyalkanoate monomer units when C-odd alkanoic acids such as nonanoic acid and heptanoic acid were fed as the sole carbon source. Solvent fractionation experiments using chloroform and hexane revealed that the 3-hydroxyalkanoate monomer units in these polyesters were copolymerized. The molar concentration of 3-hydroxyvalerate in the polyesters produced were significantly elevated up to 26 mol% by adding 1.0 g/L valeric acid as the cosubstrate. These copolyesters were sticky with low degrees of crystallinity. The PHA synthase genes were cloned, and the deduced amino acid sequences were determined. P. aeruginosa P-5 possessed genes encoding MCL-PHA synthases (PhaC1 and PhaC2) but lacked the short-chain-length PHA synthase gene, suggesting that the MCL-PHA synthases from P. aeruginosa P-5 are uniquely active for polymerizing (R)-3-hydroxyvaleryl-CoA as well as MCL (R)-3-hydroxyacyl-CoAs. | ||
| Download PDF | 48(3)_05_p.200-206_.pdf | ||