BUFF: A generic Biological Universal Forcefield for accurate predictions of Proteins and DNA in solution

Matt J. Carlson, Changmoon Park, Siddharth Dasgupta, William A. Goddard III

Materials and Process Simulation Center, Caltech

Previous forcefields for simulations of biological systems have generally used a large number of parameters to fit various experimental data. Although adequate for treating natural systems, such highly parameterized force fields do not lend themselves to simulations of new biological systems, such as those containing unnatural amino acids, modified bases, or drugs since it would be necessary to derive new parameters before doing the simulations. We prefer a generic or rule-based forcefield, which applies equally well to new amino acid types or new atoms.

The BUFF generic forcefield is based on

The robust set of charges leads to excellent electrostatic contributions to the energies.

Because all information has been obtained using a systematic method, parameters required for unusual systems can be derived without resorting to fitting empirical data. The implementation is quite general.