Fig. 4
Isobutyl acetate production in the engineered C. thermocellum. a A simplified isobutyl acetate production pathway from cellulose in C. thermocellum. b Biosynthesis of isobutyl acetate of the wild-type and engineered C. thermocellum strains at 55 °C from MTC medium with 5 g/L cellobiose and external supply of 2 g/L isobutanol. Isobutyl acetate was measured after 24 h from the hexadecane layer of cell cultures. Initial OD of each cell culture was in a range of 0.8–1.0. The error bars represent standard deviation of five biological replicates. Statistical analysis: t test, “*” p value < 4 × 10−4, t = − 6.475, df = 7. c Kinetic profiles of cell growth and residual cellulose of HSCT0102. HSCT0102 was cultured in C-MTC medium with 20 g/L Avicel PH-101. The error bars represent standard deviation of three biological replicates. d Kinetic profiles of isobutanol and isobutyl acetate production by HSCT0102 in C-MTC medium with 20 g/L Avicel PH-101. The error bars represent standard deviation of three biological replicates. KOR 2-ketoisovalerate ferredoxin oxidoreductase, ADH alcohol dehydrogenase