OPLS-AA/M force field for proteins CHARMM and Gromacs formatted parameter files for the OPLS-AA/M force field for proteins are provided below. These files have been prepared for all standard amino acids and patches. For non-standard systems, check that parameter choices are appropriate. To ensure proper implementation of the force field, geometric Lennard-Jones combining rules and 1,4 intra-nonbonded scaling should be used. A description of the parameterization procedure can be found in the following citation:

  • Robertson, M. J.; Tirado-Rives, J.; Jorgensen, W. L. Improved Peptide and Protein Torsional Energetics with the OPLS-AA Force Field. J. Chem. Theory Comput. 2015, 11 (7), 3499-3509 doi:10.1021/acs.jctc.5b00356.

OPLS-AA/M Parameter file

OPLS-AA/M Topology file

Gromacs formatted OPLS-AA/M FF was prepared as a part of LigParGen server. Please cite the following reference for LigParGen. See here for more details about the implementation and testing

  • LigParGen web server: An automatic OPLS-AA parameter generator for organic ligands..
    Dodda, L. S.; Cabeza de Vaca, I.; Tirado-Rives, J.; Jorgensen, W. L.
    Nuc. Acids Res. 2017, W1, 6665-6670 doi:10.1093/nar/gkx312.

Gromacs OPLS-AA/M force field