FIG 3.

Gluc expression and glucose consumption during culturing of strains containing hybrid promoter-Gluc constructs. K. lactis GG799 cells harboring P_GAP1-Gluc, P_ICL1-Gluc, P₁₀₀₀-Gluc, P₃₅₀-Gluc, and P₁₂₅-Gluc expression constructs were grown in YDFM containing glucose in bioreactors. Shown are (A) luciferase activity (RLU/100,000) and cell growth (OD₆₀₀) relative to hours of culturing, and (B) glucose consumption (%) and cell growth (OD₆₀₀) relative to hours of culturing. P₁₀₀₀-Gluc showed constitutive Gluc expression higher than that of P_ICL1-Gluc or P_GAP1-Gluc. P₃₅₀-Gluc showed Gluc expression only after glucose had been consumed from the culture medium. No Gluc expression was observed with P₁₂₅-Gluc. ND represents the glucose detection limit (<0.002%) of our instrumentation. Error bars represent the standard deviation from the mean of three independent fermentations.