Fig. 4From: A cell engineering approach to enzyme-based fed-batch fermentationExtracellular and cell free extract activities of D. geothermalis and C. violaceum glucoamylases following addition of exogenous signal sequences. Extracellular (dark grey) and cell free extract (light grey) activities expressed in units (defined as the disappearance of 1 mg/mL of starch/iodine complex per minute) per mL of culture. Constructs expressed in BL21(DE3) and cultured for 24 h at 25 °C, 180 rpm in LB (induced with 0.4 mM IPTG at an OD600 of 0.6–0.8). a pQR1703 (D. geothermalis glucoamylase), pQR1709 (D. geothermalis glucoamylase containing DsbAss) or pQR1710 (D. geothermalis glucoamylase containing PelB signal sequence). b pQR1705 (C. violaceum glucoamylase), pQR1711 (truncated C. violaceum glucoamylase) or pQR1712 (C. violaceum glucoamylase containing DsbA signal sequence). Error bars represent standard deviation, n = 6Back to article page