Dear gromacs users, I am doing protein-Ligand simulation using gromacs-4.6.2 with charmm36 forcefield. I have generated protein topology using pdb2gmx and ligand topology using the CGenFF-webservice and cgenff_charmm2anton.py (to convert *.str to *.itp and cordinates) <http://mackerell.umaryland.edu/download.php?filename=CHARMM_ff_params_files/cgenff_charmm2anton.py>
then I included ligand.itp to the main topology file and appended the ligand coordinates to the protein coordinates to make the protein-ligand structure coordinate file. Further steps such as editconf and genbox went smoothly. But In the grompp step, I get an error as follows, *ERROR 13 [file gd2.itp, line 248]: No default U-B typesERROR 14 [file gd2.itp, line 258]: No default U-B types......................ERROR 23 [file gd2.itp, line 371]: No default Improper Dih. types* .... Kindly help to fix this error. I also tried to defining with define = -DUSE_OLD_C36 and inculded #ifdef USE_OLD_C36 #include "old_c36_cmap.itp" in *.top #endif again obtained the same error. Please help me out here. With Regards Upendra N -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.