Molecular dynamics simulations of yeast chorismate mutase: substrate conformational transitions and enzymatic catalysis

Mol. dynamics simulations of the allosteric enzyme chorismate mutase in yeasts are presented.  QM/MM mol. dynamics simulations confirm the instability of the CHAIR conformation relative to that of other isomers in the gas phase, and confirm its relative instability in soln.  Two nonreactive conformers which are more stable in soln. than CHAIR undergo rapid transformation to the (active) CHAIR conformation by interactions with the enzyme active site.  The QM/MM potential generates transient substrate structures that are closer to the transition state than is the CHAIR conformer.