Dear all I am trying to fit a small molecule ligand into a protein complex using Coot. The data was processed to P212121, at 2.6 A. What I did was to input a SMILES string, fit the ligand, merge the ligand into the protein molecule using 'Merge Molecules' and save coordinates.
After fitting the ligand (now as chain O) I ran restrained refinement in Refmac5 and the following error returns: Input file :C:/20161226_1.1_refmac1-coot-1.pdb ------------------------------ --- LIBRARY OF MONOMERS --- _lib_name mon_lib _lib_version 5.44 _lib_update 30/05/14 ------------------------------ NUMBER OF MONOMERS IN THE LIBRARY : 13409 with complete description : 13409 NUMBER OF MODIFICATIONS : 63 NUMBER OF LINKS : 73 I am reading libraries. Please wait. - energy parameters - monomer"s description (links & mod ) FORMATTED OLD file opened on unit 45 <B><FONT COLOR="#FF0000"> Logical name: ATOMSF, Filename: C:\CCP4-7\7.0\lib\data\atomsf.lib </FONT></B> Number of atoms : 19934 Number of residues : 2577 Number of chains : 15 I am reading library. Please wait. mon_lib.cif ERROR : DUM : duplicated atom_name : "DUM ". chain: OO residue: 1 (And the error repeats itself for >100 times) I believe it is due to the nomenclature of the ligand wherein Refmac mistook atoms as DUM. (Also, the chain ID O was identified as OO?) In a test run I carried out rigid body refinement and the programme finished without issues. Is there a way I could rectify the above problem? Thanks in advance for your attention and input. Kind regards Sam Tang Biochemistry Programme, School of Life Sciences, CUHK