Common basis for the mechanism of metallo and non-metallo KDO8P synthases

Potential Energy Surface (PES) of the reaction of PEP and A5P in the presence of Zn2+ coordinated to the water that attacks PEP. The PES is defined by two reaction coordinates: formation of the bond between C3PEP and C1A5P, and formation of the bond between the oxygen of water and C2PEP. Distances are in Å, energies in kcal/mol. Colors on the PES reflect energy levels, as represented in the reference bar on the side.