Including Electronic Screening in Classical Force Field of Zinc Ion for Biomolecular Simulations

We present a new force field for zinc ion to be used in classical Molecular Dynamics. Such model has been developed according to an optimization procedure by fitting experimental quantities taken from the literature. The metal ion electrostatic charge has been scaled by a factor 0.75, according to a recently proposed polarization model which considers the electronic screening effects due to the surrounding environment. Zinc interatomic interactions have been modeled by means of the Waldman-Hagler combination rule. It is demonstrated that the proposed force field for zinc is transferable from water solution to protein catalytic sites, offering in both the considered cases good performances in the reproduction of experimental quantities usually addressed in soft matter computer simulations.