Production of 3-hydroxydecanoic acid by recombinant Escherichia coli HB101 harboring phaG gene.

Heterogenous expression of (R)-3-hydroxydecanoyl-ACP:CoA transacylase gene (phaG) isolated from Pseudomonas putida in Escherichia coli HB101 led to the extracellular production of 3-hydroxydecanoic acid (3HD) in a growth medium consisting of carbon source non-related to 3HD structure, while no 3HD was detected in the growth media inoculated with wild type E. coli HB101 and recombinant E. coli HB101 harboring vector pBluescript SK- only. 3HD production by E. coli HB101 (pLZZGPp) harboring phaG from fructose was 587 mg/l, approximately three times that from cultivation in glucose under same culture conditions. 3HD production was affected by timing of fructose addition and fructose concentration in the culture. As an inhibitor of fatty acid de novo synthesis, the presence of triclosan in the culture could increase 3HD production by E. coli HB101 (pLZZGPp) by about 20-40%. The results further confirmed that (R)-3-hydroxydecanoyl-ACP:CoA transacylase (PhaG) provides 3HD precursors for medium-chain-length polyhydroxyalkanoate synthesis. At the same time, this phenomenon showed that recombinant organisms can be used for production of certain fine chemicals such as hydroxyalkanoic acids.