BioChem - DOS

Metabolic engineering of Ralstonia eutropha for the biosynthesis of 2-hydroxyacid-containing polyhydroxyalkanoates

Metabolic engineering

Park, S.J.; Jang, Y.A.; Lee, H.; Park, A.R.; Yang, J.E.; Shin, J.; Oh, Y.H.; Song, B.K.; Jegal, J.; Lee, S.H.; Lee, S.Y.

Polyhydroxyalkanoates (PHAs) are bio-based and biodegradable polyesters synthesized by numerous microorganisms. PHAs containing 2-hydroxyacids as monomer units have attracted much attention, but their production has not been efficient. Here, we metabolically engineered Ralstonia eutropha strains for the in vivo synthesis of PHAs containing 2-hydroxyacids as monomers. This was accomplished by replacing the R. eutropha phaC gene in the chromosome with either the R. eutropha phaC S506G A510K gene, which contains two point mutations, or the Pseudomonas sp. MBEL 6-19 phaC1437 gene. In addition, the R. eutropha phaAB genes in the chromosome were replaced with the Clostridium propionicum pct540 gene. All of the engineered R. eutropha strains produced PHAs containing 2-hydroxyacid monomers, including lactate and 2-hydroxybutyrate (2HB), along with 3-hydroxybutyrate (3HB) and/or 3-hydroxyvalerate (3HV), when they were cultured in nitrogen-free medium containing 5g/L lactate or 4g/L 2HB and 20g/L glucose as carbon sources. Expression of the Escherichia coli ldhA gene in engineered R. eutropha strains allowed production of poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] from glucose as the sole carbon source. This is the first report on the production of 2-hydroxyacid-containing PHAs by metabolically engineered R. eutropha.

2013

Academic Press

1096-7176

1096-7184

20

pp.20-28

10.1016/j.ymben.2013.08.002

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART68278355

Ralstonia eutropha; PHA; 2-hydroxyacid; Lactate; 2-hydroxybutyrate