Fig. 1.

Growth pattern of the glucose-dependent E. coli strains transformed with FtglpX. JLD2402 and JLD2404 E. coli strains transformed with the pET15b-FtglpX construct were streaked onto minimal agar containing glucose (left) or glycerol (right) as the carbon source (a). The transformed strains grew on minimal agar with glycerol but not the control (untransformed) strains. E. coli strains JB108, JB108::pET15b, JB108::pET15b-FtglpX in which FtFBPaseII is expressed from the T7 promoter and BL21(DE3) (fbp ⁺ glpX ⁺) control strain were grown in minimal medium containing glycerol. The growth of JB108::pET15b-FtglpX increased in an IPTG concentration (0 to 1000 μM)-dependent manner (b). The starter culture was grown overnight in minimal medium containing glucose. The IPTG levels utilized for strain JB108::pET15b-FtglpX during growth were 0, 50, 250, 500, and 1000 μM. No IPTG was used for each of BL21(DE3) (fbp ⁺ glpX ⁺), JB108, JB108::pET15b, and JB108::pET15b-FtglpX strains, which served as controls. This experiment was repeated twice. Samples for measuring FBPase activity were withdrawn at 24 h post-IPTG induction; the cultures were also supplemented with ampicillin (100 μg/mL)