MRP.py: A Parametrizer of Post-Translationally Modified Residues.

MRP.py is a Python-based parametrization program for covalently modified amino acid residues for molecular dynamics simulations. Charge derivation is performed via an RESP charge fit, and force constants are obtained through rewriting of either protein or GAFF database parameters. This allows for the description of interfacial interactions between the modifed residue and protein. MRP.py is capable of working with a variety of protein databases. MRP.py's highly general and systematic method of obtaining parameters allows the user to circumvent the process of parametrizing the modified residue-protein interface. Two examples, a covalently bound inhibitor and covalent adduct consisting of modified residues, are provided in the Supporting Information.