title: Expression of Aeromonas caviae polyhydroxyalkanoate synthase gene in Burkholderia sp. USM (JCM15050) enables the biosynthesis of SCL-MCL PHA from palm oil products.
abstract: OBJECTIVE
  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 (phaC(Ac)) was transformed into this strain.
  
  
  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.
  
  
  CONCLUSIONS
  This is the first study demonstrating the ability of transformant Burkholderia to produce P(3HB-co-3HHx) from a single carbon source.
authors: Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors: J-Y
authors: JY
authors: Chee
authors: N-S
authors: NS
authors: Lau
authors: M-R
authors: MR
authors: Samian
authors: T
authors: T
authors: Tsuge
authors: K
authors: K
authors: Sudesh
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000378:metabolism; D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D057585:Aeromonas caviae / Q000201:enzymology / Q000235:genetics; D019117:Burkholderia / Q000201:enzymology* / Q000235:genetics* / Q000648:ultrastructure; D015964:Gene Expression Regulation, Bacterial; D046529:Microscopy, Electron, Transmission; D000073878:Palm Oil; D010938:Plant Oils / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis*; D014170:Transformation, Genetic / Q000235:genetics
chemical_list: D010938:Plant Oils; D054813:Polyhydroxyalkanoates; D000073878:Palm Oil; D000217:Acyltransferases; C077225:poly(3-hydroxyalkanoic acid) synthase; D020155:3-Hydroxybutyric Acid