Li ZJ, Shi ZY, Jian J, Guo YY, Wu Q and Chen GQ. Production of Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from Unrelated Carbon Sources by Metabolically Engineered Escherichia coli. METABOLIC ENGINEERING 12(4): 352-359, 2010

Abstract A metabolically engineered Escherichia coli has been constructed for the production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] from unrelated carbon sources. Genes involved in succinate degradation in Clostridium kluyveri and P(3HB) accumulation pathway of Ralstonia eutropha were co-expressed for the synthesis of the above copolyester. E. coli native succinate semialdehyde dehydrogenase genes sad and gabD were both deleted for eliminating succinate formation from succinate semialdehyde, which functioned to enhance the carbon flux to 4HB biosynthesis. The metabolically engineered E. coli produced 9.4 gl(-1) cell dry weight containing 65.5% P(3HB-co-11.1 mol% 4HB) using glucose as carbon source in a 48 h shake flask growth. The presence of 1.5-2 gl(-1) alpha-ke......