Fig. 3

Effect of pantothenate on P(3HB) production in E. coli containing the exogenous coaA gene. The transformants of E. coli JM109/pSTV28 + pQE-Ma-phaABEC (circles) and JM109/pSTV-Pp-coaA + pQE-Ma-phaABEC (triangles) were grown in 30 mL of minimal medium containing 2% (w/v) glucose and various concentrations of pantothenate without 0.1 mM IPTG for 48 h at 30 °C (closed symbols) or 37 °C (open symbols). Cellular P(3HB) was converted into 3HB methyl esters and measured using GC-FID. The P(3HB) content is indicated as % (w/w) of dry cell weight (A) and g/L (B). Cell mass is expressed in g of dry cell weight per 1 litter (C). True cell mass was calculated by subtracting P(3HB) from cell mass (D). The significant difference between coaA – and + at each concentration of pantothenate was compared using an unpaired Student's t-test: *, p < 0.05; **, p < 0.01; ***, p < 0.001. The data are shown as the mean ± SD (n = 3)