Figure 2.

The proposed de novo biosynthetic pathway for MPLA production. LPS biosynthesis and the proposed de novo biosynthetic pathway for MPLA. E. coli evolved to incorporate Kdo sugar units via Kdo transferase KdtA before addition of the lauroyl and myristoyl groups by LpxL and LpxM, respectively, during LPS biogenesis (green-colored box). A proposed MPLA biosynthetic pathway in E. coli is shown in the orange-colored box (blue-colored pathway). Red crosses indicate the necessary gene knockouts for generating the MPLA-producing strains. LpxT and PagP potentially compete with LpxE for lipid A as a substrate (purple-colored box).