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<DIV><FONT face=Arial size=2>Dear All</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I’m using distance restraints to force proper
orientation of the ligand in the active site of the receptor protein
(I’m investigating different binding modes).<BR>I encountered a strange problem
when defining distance restraints.<BR>I have protein and ligand topology
combined in one itp file.<BR>At the end of this topology file (itp) I defined
atoms pairs for distance restraints:<BR>….<BR>[ distance_restraints ]<BR>;
ai aj type
index type low
up1 up2 fac<BR> 1384
4036 1
0
1 0.0 0.15
0.25 2.0<BR> 2957 4046
1
1
1 0.0 0.15
0.25 2.0<BR> 2957 4057
1
1
1 0.0 0.15
0.25 2.0</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>When looking at trajectory file I noticed that
restraints are present but not between defined atoms but probably between
pairs:</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>1383 4035<BR>2956 4045<BR>2956 4056</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I checked the tpr file: gmxdump_mpi3 -s
posre100.tpr and I found that position restraints are not between defined pairs
but rather between
(atom-1,atom-1).<BR>…<BR>Dis.
Rest.:<BR> nr:
9<BR>
multinr[division over processors]: 9 9 9 9 9 9 9 9 9 9 9 9
…<BR>
iatoms:<BR>
0 type=1244 (DISRES) 1383
4035<BR>
1 type=1245 (DISRES) 2956
4045<BR>
2 type=1245 (DISRES) 2956 4056<BR>…</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Numbering of atoms in my topology file is correct
so I guess it’s not the case. What might be the problem. Am I doing
something wrong. I’m using gromacs3.3. Please give me comment on this
and thank you for help.<BR></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Best
regards<BR>Michal<BR></DIV></FONT></BODY></HTML>