Formation of polyhydroxyalkanoate blends by Pseudomonas pseudoalcaligenes M1–2 from various carbon sources

Pseudomonas pseudoalcaligenes strain MI-2 isolated from oil-contaminated soil collected from an oilfield in northern China was found to be able to synthesize a blend of polyhydroxyalkanoates (PHAs) containing monomers of 3-hydroxybutyrate (C4), 3-hydroxyvalerate (C5), 3-hydroxyheptanoate (C7), 3-hydroxyoctanoate (C8), 3-hydroxynonanoate (C9), 3-hydroxydecanoate (C10) and 3-hydroxydodecanoate (C12) from various carbon sources. The hydroxyalkanoate (HA.) monomer composition varied both quantitatively and qualitatively, depending on the carbon sources used. The presence of octanoate in substrates of myristic acid or tridecanoate promoted the synthesis of HB monomer in the blend. Concentration of octanoate was also found to significantly affect the PHB content in the blend. A PHA biosynthesis pathway in Pseudomonas pseudoalcaligens M1–2 was proposed.