[gmx-users] g_sas and -qmax

David spoel at xray.bmc.uu.se
Sun Apr 4 17:44:00 CEST 2004


On Sun, 2004-04-04 at 16:28, Michael Brunsteiner wrote:
> dear all,
> I would like to calculate solvent accessible surface areas 
> in my system. I find that the g_sas program that comes 
> with gromacs has an argument qmax for giving a threshold
> above which an atom is to be considered as hydrophilic. 
> I wonder if the default value for this number (0.2 e) is
> 1) an educated guess
> 2) derived from experimental data, or
> 3) derived theoretically ?
> I'd be also grateful if somebody could point me to 
> literature discussing this topic.
1
Evrything called hydrophilic has a larger charge in both OPLS and GROMOS
force fields. With this value aromatic as well as CH3 groups in OPLS are
still considered hydrophobic (C in CH3 has -0.18e).

No literature...
> cheers,
> Michael
> 
> 
> __________________________________
> Do you Yahoo!?
> Yahoo! Small Business $15K Web Design Giveaway 
> http://promotions.yahoo.com/design_giveaway/
> _______________________________________________
> gmx-users mailing list
> gmx-users at gromacs.org
> http://www.gromacs.org/mailman/listinfo/gmx-users
> Please don't post (un)subscribe requests to the list. Use the 
> www interface or send it to gmx-users-request at gromacs.org.
-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assist. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://xray.bmc.uu.se/~spoel
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++




More information about the gromacs.org_gmx-users mailing list