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<div>Dear Ganesh,</div>
<div> </div>
<div>You can also use the ATB site, and convert the all atom .itp to CHARM36 format, or build it (charge, bond, angles, etc...) from the already present CHARMM36 atom parameters. Check your charges if you get them from the ATB.</div>
<div> </div>
<div>Stephan Watkins</div>
<div> </div>
<div>On 1/22/16 8:51 AM, Ganesh Shahane wrote:<br/>
> Dear Gromacs users,<br/>
><br/>
> I wish to simulate a mixed lipid bilayer of which one of the lipids is<br/>
> sphingomyelin (PSM, 18:1-sphingosine and 16:0-palmitic acid) using Charmm36<br/>
> ff. Towards this, I constructed the bilayer using Charmm-GUI but then was<br/>
> surprised to find that its topology is not present in residue topology<br/>
> database of Charmm36 ff.<br/>
><br/>
> Does anyone has any idea about where can I get topology for PSM? Or would<br/>
> it be wise to submit it to paramchem to get its topology?<br/>
><br/>
<br/>
Use the force field CHARMM-GUI provides you. It supports everything in your<br/>
system. Our charmm36.ff port may not include everything; I extend it only when<br/>
people ask for specific parameters (as CHARMM is a huge force field, sometimes<br/>
things get missed and I rely on this kind of feedback). I'll add sphingomyelin<br/>
in the next release.<br/>
<br/>
-Justin<br/>
<br/>
--<br/>
==================================================<br/>
<br/>
Justin A. Lemkul, Ph.D.<br/>
Ruth L. Kirschstein NRSA Postdoctoral Fellow<br/>
<br/>
Department of Pharmaceutical Sciences<br/>
School of Pharmacy<br/>
Health Sciences Facility II, Room 629<br/>
University of Maryland, Baltimore<br/>
20 Penn St.<br/>
Baltimore, MD 21201<br/>
<br/>
jalemkul@outerbanks.umaryland.edu | (410) 706-7441<br/>
<a href="https://3c.gmx.net/mail/client/dereferrer?redirectUrl=http%3A%2F%2Fmackerell.umaryland.edu%2F%7Ejalemkul" target="_blank">http://mackerell.umaryland.edu/~jalemkul</a><br/>
<br/>
==================================================<br/>
<br/>
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