This API is currently available in C++ and Python.

bool OEFixBackbone(OEBio::OEDesignUnit& du)

The function attempts to correct missing oxygen atoms on the protein backbone, O and OXT, as well as correct the charge and valence state. If any of the core backbone atoms, N, CA, or C are missing it removes the residue. The proper residue can be modeled in later using OEBuildLoops.