Hello, I would like to simulate the glucose polymer dextran (~5-10 subunits) and I am wondering what is the best way to do go about doing this. In looking at ffgmx.rtp I see GLCA/B which seem to be the glucose parameter files. If my numbering scheme is correct, to produce a linear dextran molecule I want alpha(1-6) linkages, or alpha(1-4) linkages for a branched polymer which would correspond to O6-C1 and O3-C1 respectively. However, in the .rtp file, these bonds are not given, only O4-C1 and O2-C1 are included. Is my numbering off, or is there another way to do this? I have tried the PRODRG server to create these molecules, and it seemed to work alright, but I am still a little skeptical about the output. The charges appear to be different than in the ffgmx. I understand that ffgmx is depreciated, which leads to me second question (Maybe this should be a different thread). I would like, eventually, to look at the different dextran polymers interacting with a DPPC bilayer. For the lipids, I am using those of Dr. P. Tieleman in which my dppc.top file includes ffgmx.itp which is why I am looking at this force field for the dextran. If ffgmx is not a force field to use, what would be better for simulating lipids and carbohydrates? ffG43a2x? I have read for protein simulations people using the Berger lipids and OPLS-AA, would it be fair to extend this to lipids and carbohydrates?
Thanks, Mike Tomasini _______________________________________________ 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 [EMAIL PROTECTED] Can't post? Read http://www.gromacs.org/mailing_lists/users.php