Residue-Residue Position/Orientation Database Restraint

This is a PDB database-derived potential that orients one residue relative to another. Each residue is used as a reference for those around it. A four-dimensional Gaussian is used to generate an energy surface for three atoms from the target base. As those three atoms move, the rest of the base is forced to follow by the covalent constraints. At this time this term has only been implemented for nucleic acid base-base interactions. The references for this potential are Kuszewski, Schwieters, and Clore (2001) and Clore and Kuszewski (2003).