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<DIV><FONT face=Arial size=2>Dear All<BR>I have question for people who
use dppc lipids with ffG43a2x.tgz force field <BR>(GROMOS96 modified to describe
lipids). I want to change to newer GROMOS96 <BR>force field (in order to
simulate membrane/protein water systems) and I would <BR>like to make *.itp file
for dppc lipid molecule that is in agreement with <BR> ffG43a2x.tgz
from the contribution section of gromacs website. <BR> ffG43a2x.tgz force
field has two new atoms types LCH3 and LCH2 that can be<BR>used to describe long
lipid chains. There are also new LJ parameters for <BR>those atoms in
ffG43a2xnb.itp. What is the procedure for obtaining *itp <BR>for
dppc molecule that can be used with this force field.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>1) Should I use PRODRGbeta for creating
dppc.itp topology and <BR>manually change atom types describing lipid long
chains CH3 to LCH3 and then CH2 to LCH2.<BR>2) Should I download dppc.itp
topology from gromacs benchmark <BR>and manually change the atom types to those
present in ffG43a2x. <BR>3) Is there any available software that can be
used for <BR>creation of dppc.itp file.<BR>4) .. is there a simpler
way?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Please give me some hints and suggestion,<BR>I’m
not an expert with gromacs, what is the <BR>right procedure for this. <BR>Thank
you for your help. <BR>Best Regards. <BR></FONT></DIV></BODY></HTML>