On 5/24/12 8:19 AM, rama david wrote:
Thank you for your reply,

I am asking you again same question, EXTREMELY SORRY for my stupidity,

In step six , I unable to differentiate npt and production run by
mdp file as usualy we find difference by define term,

I think I get meaning upto reason why to use -DPOSRES_B,
but I want to know if we are using same mdp file in both condition
means the npt equilibriation is as same as md production ,

Then why to do npt, just run production md  with  DPOSRES_B


I'm not sure of what the question is exactly, so my apologies if the following explanation does not answer it. For the tutorial, NPT is conducted with restraints on all protein heavy atoms. The production runs are conducted by restraining only one chain for practical reasons.

Don't confuse yourself by always assuming that the difference between NPT and production runs is the use of define statements or position restraints. There are many ways of doing equilibration. NPT of a protein in solvent is typically done with restraints on the protein, allowing the solvent to relax and avoiding potential geometric distortions due to bad solvent contacts. Production runs may or may not make use of any restraints. Their use is dependent upon the situation at hand and whether or not they are appropriate.

I hope this explanation makes everything clear.

-Justin

--
========================================

Justin A. Lemkul, Ph.D.
Research Scientist
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    [email protected]
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at 
http://www.gromacs.org/Support/Mailing_Lists/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/Support/Mailing_Lists

Reply via email to