[gmx-users] Two different force field use in one simulation?

[Justin Lemkul]

On 10/26/16 5:28 AM, Mijiddorj Batsaikhan wrote:
> Dear gmx users,
>
> I would like to simulate a system that consists of 2 different membranes
> and protein molecule. DOPI membrane model could not find from Charmm-gui
> ,embrane builder's models. I built the system DMPI membrane instead of
> DOPI. Then I modified DMPIs to DOPIs, and got charmm27 force field
> parameters using swissparam. Charmm-gui give me charmm36 parameters. I want
> to use charmm27 for only DOPI. I have some questions.
>
> (1) Is these type of modification possible to the simulations?
>
> (2)  How can I convert charmm27 to charmm36 parameter?
>

You can't just convert one force field to another.  CHARMM36 is superior to the 
outdated CHARMM27 for lipids, so it is a much better force field model for doing 
current simulations.

-Justin

-- 
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Justin A. Lemkul, Ph.D.
Ruth L. Kirschstein NRSA Postdoctoral Fellow

Department of Pharmaceutical Sciences
School of Pharmacy
Health Sciences Facility II, Room 629
University of Maryland, Baltimore
20 Penn St.
Baltimore, MD 21201

jalemkul at outerbanks.umaryland.edu | (410) 706-7441
http://mackerell.umaryland.edu/~jalemkul

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