Authors: Daniel Heinrich, Matthias Raberg, Philipp Fricke, Shane T Kenny, Laura Morales-Gamez, Ramesh P Babu, Kevin E O’Connor, Alexander Steinbüchel
Publication Date: 10/15/2016
Journal: Applied and environmental microbiology
Volume: 82
Issue: 20
Pages: 6132-6140
Publisher: American Society for Microbiology
The purple nonsulfur alphaproteobacterium Rhodospirillum rubrum S1 was genetically engineered to synthesize a heteropolymer of mainly 3-hydroxydecanoic acid and 3-hydroxyoctanoic acid [P(3HD-co-3HO)] from CO- and CO2-containing artificial synthesis gas (syngas). For this, genes from Pseudomonas putida KT2440 coding for a 3-hydroxyacyl acyl carrier protein (ACP) thioesterase (phaG), a medium-chain-length (MCL) fatty acid coenzyme A (CoA) ligase (PP_0763), and an MCL polyhydroxyalkanoate (PHA) synthase (phaC1) were cloned and expressed under the control of the CO-inducible promoter P cooF from R. rubrum S1 in a PHA-negative mutant of R. rubrum. P(3HD-co-3HO) was accumulated to up to 7.1% (wt/wt) of the cell dry weight by a recombinant mutant strain utilizing exclusively the provided gaseous feedstock syngas. In addition to an increased synthesis of these medium-chain-length …
