Dear Gromacs Users, Thanks Justin and Marc for the response and you were right.
As suggested, i had a view in the modelled protein pdb file and here both the terimus are capped that is as follows; ATOM 1 N THR A 62 -43.095 3.360 19.026 1.00 30.00 N1+ ATOM 4804 OXT PRO A 355 -53.907 34.064 13.899 1.00110.00 O1- then i tried to execute the pdb2gmx command as under, (which i did earlier also): pdb2gmx -f damgomu.pdb -o damgomu_processed.gro -ignh -ter -water spc and selected the "Gromos96 53a6" parameter and "none" options, then the warnings and errors where as follows: Now there are 294 residues with 3043 atoms Making bonds... Warning: Long Bond (12-14 = 0.65447 nm) Warning: Long Bond (1975-1977 = 4.21722 nm) Warning: Long Bond (2050-2052 = 3.24295 nm) Opening library file /usr/local/gromacs/share/gromacs/top/aminoacids.dat WARNING: atom H is missing in residue THR 1 in the pdb file You might need to add atom H to the hydrogen database of residue THR in the file ff???.hdb (see the manual) Fatal error: There were 1 missing atoms in molecule Protein_A, if you want to use this incomplete topology anyhow, use the option -missing and in the previous run i concatenated -missing option and continued further, then the toplogy was written with the charge of Total charge 12.690 e ,but still the warning persisted of missing H atom in THR1. Please suggest me how to rectify this error and why the total number of atoms in pdb file (4815) are not matching even though the number of residues are matching after pdb2gmx step. Thanks, Ram and selected choose the "Gromos96 53a6" parameter and "none" options On Tue, Sep 29, 2009 at 7:04 PM, Justin A. Lemkul <jalem...@vt.edu> wrote: > > > ram bio wrote: >> >> Dear Gromacs users, >> >> I have a modelled protein whose net charge is +12.69, and I would like to >> ionize the protein to make it neutral using genion command, but in genion >> command we can add a specific number of postive or negative charged ions >> which for my case would not completely neutralize the system and i learnt >> from Justin tutorial that we can even neutralize it using -conc and -neutral >> options in conjugation. As I am running a membrane-protein simulation, I >> would like to know the command which I am using is correct or not. >> >> genion -s ions.tpr -o protein_solv_ions.gro -p topol.top -pname NA+ -nname >> CL- -nn 12 -neutral >> >> If my command is wrong Please suggest the right one as In future i have to >> conjugate SOL and CL- ions to create a special index file. >> >> > > If your protein has a net charge of +12.69, it is probably wrong. Does > anything in real life have such a net fractional charge? > > Go back and evaluate what you have done. Are there missing atoms? Wrong > parameters? The genion command you want to use is fine, but is not suitable > for your system in its current state. > > -Justin > >> Thanks >> >> Ram >> >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> gmx-users mailing list gmx-users@gromacs.org >> http://lists.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 > > -- > ======================================== > > Justin A. Lemkul > Ph.D. Candidate > ICTAS Doctoral Scholar > Department of Biochemistry > Virginia Tech > Blacksburg, VA > jalemkul[at]vt.edu | (540) 231-9080 > http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin > > ======================================== > _______________________________________________ > gmx-users mailing list gmx-users@gromacs.org > http://lists.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 _______________________________________________ gmx-users mailing list gmx-users@gromacs.org http://lists.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