When I use:<br>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; self.patch(residue_type=&#39;DISU&#39;, residues=(self.residues[&#39;199&#39;],<br>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; self.residues[&#39;205&#39;]))<br>it works. <br>When I use:
<br>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; self.patch(residue_type=&#39;DISU&#39;, residues=(self.residues[&#39;199:G&#39;],<br>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; self.residues[&#39;205:G&#39;]))<br>it gives me error information:
<br>KeyError: &#39;No such residue: 199:G&#39;<br><br>What might be wrong?<br>Thanks!<br><br>------<br>Atila Iamarino wrote:<br>&gt; I&#39;m interested in modeling a protein forcing 
disulfide bridges but my <br>&gt; protein has two chains. How do I set the 
residue in the .py file?<br>&gt; <br>&gt; # Redefine the special_patches routine 
to include the additional disulfides<br>&gt; # (this routine is empty by 
default):<br>&gt; class mymodel(automodel):<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp; def 
special_patches(self, aln):<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # A disulfide between residues 8 and 
45:<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; self.patch(residue_type=&#39;DISU&#39;, 
residues=(self.residues[&#39;8&#39;],<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
self.residues[&#39;45&#39;]))<br><br>That&#39;s straightforward - just include a chain ID 
(see <br><a href="http://salilab.org/modeller/9v1/manual/node153.html">http://salilab.org/modeller/9v1/manual/node153.html</a>). 
For example,<br><br>&nbsp;&nbsp;&nbsp;&nbsp; self.patch(residue_type=&#39;DISU&#39;, 
residues=(self.residues[&#39;8:A&#39;],<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
self.residues[&#39;45:A&#39;]))<br><br>Ben Webb, Modeller Caretaker<br><br><br>