title: Expression of poly-3-(R)-hydroxyalkanoate (PHA) polymerase and acyl-CoA-transacylase in plastids of transgenic potato leads to the synthesis of a hydrophobic polymer, presumably medium-chain-length PHAs.
abstract: Medium-chain-length poly-3-(R)-hydroxyalkanoates (mcl-PHAs) belong to the group of microbial polyesters. The minimum gene-set for the accumulation of mcl-PHAs from de novo fatty acid biosynthesis has been identified in prokaryotes as consisting of the Pha-C1 polymerase and the ACP-CoA-transacylase. In this paper, the synthesis of mcl-PHAs has been attempted in transgenic potato (Solanum tuberosum L.) using the same set of genes that were introduced into potato by particle bombardment. Polymer contents of transgenic lines were analysed by gas chromatography and by a new simple method employing a size-exclusion filter column. The expression of the Pha-C1 polymerase and the ACP-CoA-transacylase in the plastids of transgenic potato led to the synthesis of a hydrophobic polymer composed of mcl-hydroxy-fatty acids with carbon chain lengths ranging from C-6 to C-12 in leaves of the selected transgenic lines. We strongly suggest that the polymer observed consists of mcl-PHAs and that this report establishes for the first time a possible route for the production of mcl-PHAs from de novo fatty acid biosynthesis in plants.
authors.affiliation: Agrotechnology and Food Innovations B.V., Department of Bioconversion, Wageningen University and Research Centre, POB 17, 6700 AA, Wageningen, The Netherlands.
authors.forename: Andrea
authors.initials: A
authors.lastname: Romano
authors.forename: Linus H W
authors.initials: LH
authors.lastname: van der Plas
authors.forename: Bernard
authors.initials: B
authors.lastname: Witholt
authors.forename: Gerrit
authors.initials: G
authors.lastname: Eggink
authors.forename: Hans
authors.initials: H
authors.lastname: Mooibroek
mesh_terms: D000217:Acyltransferases / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D015870:Gene Expression; D005798:Genes, Bacterial; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000378:metabolism; D018087:Plastids / Q000378:metabolism*; D044204:Pseudomonas oleovorans / Q000235:genetics; D016958:Pseudomonas putida / Q000235:genetics; D011198:Solanum tuberosum / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D000217:Acyltransferases; C077225:poly(3-hydroxyalkanoic acid) synthase; C067032:poly(3-hydroxyalkenoate)polymerase