Qian Wang & Xiaolong Liu & Qingsheng Qi
Appl Microbiol Biotechnol (2014) 98:3923–3931
The biosynthesis of polyhydroxyalkanoate copolymers in Escherichia coli from unrelated carbon sources becomes attractive nowadays. We previously developed a poly(hydroxybutyrate-co-hydroxyvalerte) (PHBV) biosynthetic pathway from an unrelated carbon source via threonine metabolic route in E. coli(Chen et al.,Appl Environ Microbiol 77:4886-4893, 2011). In our study, a citramalate pathway was introduced in recombinant E. coli by cloning a cimAgene from Leptospira interrogans. By blocking the pyruvate and the propionyl-CoA catabolism and replacing the β-ketothiolase gene, the PHBV with 11.5 mol% 3HV fraction was synthesized. Further, the combination of citramalate pathway with the threonine biosynthesis pathway improved the 3HV fraction in PHBV copolymer to 25.4 mol%in recombinant E. coli.