Molecular modelling of lipase-catalyzed polyester synthesis
Molecular dynamics simulations and electrostatic potential calculations were used to study the structure of a Rhizomucor miehei lipase (RmL)–substrate complex in a lipase catalyzed polyester synthesis. Two lipase–substrate complexes were constructed with sebacic acid and 1,4-butyl sebacate as substrates, energy minimized, and simulated for 100 ps. During the simulation, catalytically important hydrogen bonds were formed more easily, when the acid was placed in the hydrophobic end and the ester in the hydrophilic end of the active centre. However, also the polarity of the active centre amino acids probably affects the placement of the substrates. The electrostatic potential calculations showed significant differences in the electrostatic potential of the surface of RmL. This may help the lipase to orientate itself appropriately for the interfacial reaction.