Dataset for: Quantum chemical modeling of the reaction path of chorismate mutase based on the experimental substrate/product complex

posted on 12.05.2017 by Daniel Burschowsky, Ute Krengel, Einar Uggerud, David Balcells
Chorismate mutase is a well-known model enzyme, catalyzing the Claisen rearrangement of chorismate to prephenate. Recent high-resolution crystal structures along the reaction coordinate of this enzyme enable computational analyses at unprecedented detail. Using quantum chemical simulations, we have investigated how the catalytic reaction mechanism is affected by electrostatic and hydrogen bond interactions. Our calculations showed that the transition state was mainly stabilized electrostatically, with Arg90 playing the leading role. The effect was augmented by selective hydrogen bond formation to the transition state in the wild-type enzyme, facilitated by a small-scale local induced fit. We further identified a previously underappreciated water molecule, which separates the negative charges during the reaction. The analysis includes the wild-type enzyme and a non-natural enzyme variant, where the catalytic arginine was replaced with an isosteric citrulline residue.