On Sunday, Feb 1, 2004, at 17:18 Europe/Berlin, Konrad Hinsen wrote: > The bug is in the database definition file for the peptide group of > C-terminal proline, which has O1 and O2 instead of the PDB standard > names O and OXT. Just put the attached files into MMTK/Database/Groups > and your script works fine. Thanks. That did the trick. Urban