Reactive & Functional Polymers, Vol.48, No.1-3, 107-112, 2001
Synthesis of copolyesters consisting of medium-chain-length beta-hydroxyalkanoates by Pseudomonas stutzeri 1317
Strain Pseudomonas stutzeri 1317 was able to synthesize a variety of polyhydroxyalkanoates (PHAs) when grown in glucose and/or fatty acids. The monomer structures of the PHAs were found to be dependent on the structures of related fatty acids. Up to ten PHA monomers have been found in PHAs, including 3-hydroxybutyrate (HB), 3-hydroxyvalerate (HV), 3-hydroxyhexanoate (HHx), 3-hydroxyheptanoate (HHp), 3-hydroxyoctanoate (HO), 3-hydroxynonanoate (HN), 3-hydroxydecanoate (HD), 3-hydroxyundecanoate (HU), 3-hydroxydodecanoate (HDD) and 3-hydroxytetradecanoate (HTD). In the presence of butyric acid, valeric acid to nonanoic acid, HE, HV to HN were all synthesized. Mixed substrates of glucose and fatty acids led to the formation of fatty acid structure related PHA monomers. Monomer percentage contents in PHA could be adjusted by regulating ratios of fatty acids in growth substrates. During cell growth in glucose and octanoic acid, the addition of heptanoic acid stimulated the rapid synthesis of HHp in PHA. It can be concluded that PHA structures can be tailor made by using structure-related fatty acids and varying ratios of fatty acids.