Figure 1.

A novel pathway for butanol and isobutanol production. Metabolic pathway for butanol and isobutanol production from glycine in S. cerevisiae through the glyoxylate, β-ethylmalate and α-ketoacids intermediates (grey background arrows). The enzymatic activities involved and the associated gene(s) are also represented. Numbers inside circles indicates the steps of the pathway discussed in this study. The hypothesized isomerisation of α-ketovalerate into α-isoketovalerate is indicated by black arrow.