The group of SUN Jibin at Tianjins Institute of Industrial Biotechnology rationally designed and experimentally engineered Corynebacterium glutamicum to serve as a methanol-dependent synthetic methylotroph. The cell growth of the methanol-dependent strain relies on co-utilization of methanol and xylose, and methanol is an indispensable carbon source. Due to the methanol-dependent characteristic, adaptive laboratory evolution was successfully applied to improving methanol utilization. The evolved mutant showed a 20-fold increase in cell growth on methanol-xylose minimal medium and utilized methanol and xylose with a high mole ratio of 3.83:1. 13C-labeling experiments demonstrated that the carbon derived from methanol was assimilated into intracellular building blocks, high-energy carriers, cofactors, and biomass (up to 63% 13C-labeling). By inhibiting cell wall biosynthesis, methanol-dependent glutamate production was also achieved, demonstrating the potential application in bioconversion of methanol into useful chemicals.
CAS news release, August 28, 2018