Hi Justin and all when I do this command: pdb2gmx -ignh -f .pdb -o .pdb -water spce with OPLS force field. it seems that the protein has the charge of -3, while the ligand has the charge of 0.890 and finally it prints that the final charge is -2.11. I neutralized this charge with 2 NA+ so -0.11 charge remain (sorry for my mistake this is 0.11 not 0.08).
Opening library file /usr/local/gromacs/share/gromacs/top/aminoacids.dat Number of bonds was 3653, now 3653 Generating angles, dihedrals and pairs... Before cleaning: 9612 pairs Before cleaning: 9677 dihedrals Keeping all generated dihedrals There are 9677 dihedrals, 699 impropers, 6622 angles 9552 pairs, 3653 bonds and 0 virtual sites Total mass 25805.536 a.m.u. Total charge -3.000 e Writing topology Back Off! I just backed up posre_A.itp to ./#posre_A.itp.2# Processing chain 2 'R' (12 atoms, 1 residues) Checking for duplicate atoms.... Now there are 11 atoms. Deleted 1 duplicates. Opening library file /usr/local/gromacs/share/gromacs/top/specbond.dat 6 out of 6 lines of specbond.dat converted succesfully N-terminus: NH3+ C-terminus: COO- Now there are 1 residues with 27 atoms Chain time... Back Off! I just backed up topol_R.itp to ./#topol_R.itp.2# Making bonds... Opening library file /usr/local/gromacs/share/gromacs/top/aminoacids.dat Number of bonds was 26, now 26 Generating angles, dihedrals and pairs... Before cleaning: 60 pairs Before cleaning: 60 dihedrals Keeping all generated dihedrals There are 60 dihedrals, 5 impropers, 45 angles 60 pairs, 26 bonds and 0 virtual sites Total mass 175.212 a.m.u. Total charge 0.890 e Writing topology Back Off! I just backed up posre_R.itp to ./#posre_R.itp.2# Including chain 1 in system: 3623 atoms 226 residues Including chain 2 in system: 27 atoms 1 residues Now there are 3650 atoms and 227 residues Total mass in system 25980.748 a.m.u. Total charge in system -2.110 e What should I do to my ligand charge in order to have complete charge? thanks -- Tehran University of Medical Sciences www.tums.ac.ir -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. _______________________________________________ gmx-users mailing list gmx-users@gromacs.org http://www.gromacs.org/mailman/listinfo/gmx-users Please search the archive at http://www.gromacs.org/search before posting! Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. Can't post? Read http://www.gromacs.org/mailing_lists/users.php