Expression of Aeromonas caviae polyhydroxyalkanoate synthase gene in Burkholderia sp. USM (JCM15050) enables the biosynthesis of SCL-MCL PHA from palm oil products
Article first published online: 25 NOV 2011
© 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology
Journal of Applied Microbiology
Volume 112, Issue 1, pages 45–54, January 2012
How to Cite
Chee, J.-Y., Lau, N.-S., Samian, M.-R., Tsuge, T. and Sudesh, K. (2012), Expression of Aeromonas caviae polyhydroxyalkanoate synthase gene in Burkholderia sp. USM (JCM15050) enables the biosynthesis of SCL-MCL PHA from palm oil products. Journal of Applied Microbiology, 112: 45–54. doi: 10.1111/j.1365-2672.2011.05189.x
- Issue published online: 13 DEC 2011
- Article first published online: 25 NOV 2011
- Accepted manuscript online: 6 NOV 2011 09:23PM EST
- 2011/0681: received 21 April 2011, revised 17 August 2011 and accepted 27 October 2011
- Burkholderia sp.;
- palm oil;
- PHA synthase;
Aims: Burkholderia sp. USM (JCM15050) isolated from oil-polluted wastewater is capable of utilizing palm oil products and glycerol to synthesize poly(3-hydroxybutyrate) [P(3HB)]. To confer the ability to produce polymer containing 3-hydroxyhexanoate (3HHx), plasmid (pBBREE32d13) harbouring the polyhydroxyalkanoate (PHA) synthase gene of Aeromonas caviae (phaCAc) was transformed into this strain.
Methods and Results: The resulting transformant incorporated approximately 1 ± 0·3 mol% of 3HHx in the polymer when crude palm kernel oil (CPKO) or palm kernel acid oil was used as the sole carbon source. In addition, when the transformed strain was cultivated in the mixtures of CPKO and sodium valerate, PHA containing 69 mol% 3HB, 30 mol% 3-hydroxyvalerate and 1 mol% 3HHx monomers was produced. Batch feeding of carbon sources with 0·5% (v/v) CPKO at 0 h and 0·25% (w/v) sodium valerate at 36 h yielded 6 mol% of 3HHx monomer by controlled-feeding strategies.
Conclusions: Burkholderia sp. USM (JCM15050) has the metabolic pathways to supply both the short-chain length (SCL) and medium-chain length (MCL) PHA monomers. By transforming the strain with the Aer. caviae PHA synthase with broader substrate specificity, SCL-MCL PHA was produced.
Significance and Impact of the Study: This is the first study demonstrating the ability of transformant Burkholderia to produce P(3HB-co-3HHx) from a single carbon source.