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Hi everyone,<BR>
I had asked this question before but I will try to explain myself more clearly.<BR>
<BR>
I wan t to add -NH2 cap at the Cterminal end of my protein. I had included "charmm" force <BR>
field into my gromacs 3.3.1.<BR>
I had added the following into my ffcharmm-c.tdb file<BR>
[NH2]<BR>
[replace]<BR>
O OB 15.994 -0.550<BR>
CA CT1 12.0110 0.070<BR>
C CD 12.0110 0.720<BR>
[add]<BR>
1 4 NH2 C CA C<BR>
NH2 14.0027 -0.7800<BR>
2 3 HT N CA C<BR>
HT 1.0080 0.3100<BR>
However, the coordinates of the added N is given by "pdb2gmx" as " nan nan nan".<BR>
If anyone can give any suggestion to fix this poblem, I will be highly obliged.<BR>
<BR>
Thanks in advance,<BR>
Sarbani<BR>
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