[gmx-users] CHARMM36 GROMACS implementation

[Justin Lemkul]

On 11/19/18 11:32 AM, John Whittaker wrote:
> Hi all,
>
> I am trying to reproduce the pure DPPC bilayer data found in J. Chem.
> Theory Comput., 2016, 12 (1), pp 405–413 (10.1021/acs.jctc.5b00935) using
> the recommended protocol given in the paper.
>
> Recently, I realized I made a mistake and have been using the CHARMM36
> forcefield provided by Tom Piggot here
> (http://www.gromacs.org/Downloads_of_outdated_releases/User_contributions/Force_fields)
> rather than the official CHARMM36 implementation found on the MacKerell
> lab's site (http://mackerell.umaryland.edu/charmm_ff.shtml).
>
>  From what I understand from its description in the force field
> documentation and the accompanying paper, the version provided by Tom
> Piggot should not affect my results because the lipid parameters from
> CHARMM36 are unchanged (while the protein parameters are) and my system
> consists only of water and DPPC.
>
> Am I right to assume that my results should be (theoretically) reflective
> of those that I would obtain from using the using the full CHARMM36 force
> field?

The lipids should all be the same. A single-point energy/force 
evaluation under both force fields would confirm this.

-Justin

-- 
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Justin A. Lemkul, Ph.D.
Assistant Professor
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Virginia Tech Department of Biochemistry
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jalemkul at vt.edu | (540) 231-3129
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