Dear Gromacs users!<br><br>I've forced with some problem of preparing topology of my input pdb via pdb2gmx.<br><br>My input structure( gramicidin ion chanell) consist of some heteroatoms due to the presence of the non standart aminoacids in sequence: FOR, DLE, DVA, ETA ( this the R isomers instad of L analogs)<br>
<br><br>I've tried to parametriesed that structure via different force fields but in all cases there are not suitable topologies for that aminoacids<br><br>e.g<br>Fatal error:<br>Residue 'FOR' not found in residue topology database<br>
<br>How I can solve that problem? I've tried to look for the suitable itp file but could not find it too :(<br><br>James<br>