The group around Professor MA Yanghe activated transhydrogenase and NAD kinase in constitutively stable strains of E. coli. Under anaerobic conditions, isobutyl alcohol yield increased to 39% (0.92 mol/mol), close to the theoretical value. Under aerobic conditions, isobutyl alcohol yield increased by by 22%; within 24 hours, 10.8 g/l isobutanol were produced, and production rate was 0.62 mol/mol.

Source: http://dx.doi.org/10.1016/j.ymben.2012.11.008