Hi,<br>
<br>
I had a trouble of refining &quot;ATP&quot; in Phenix. I appreciate any help.<br>
<br>
ATP with  tri-phosphate is in the 5&#39; end of RNA chain. It is added to 
the RNA chain in coot as a monomer &quot;ATP&quot;, and it could be connected to 
the downstream base after I changed the &quot;_chem_comp.group&quot; option to 
&quot;RNA&quot; in the cif file.<br>
<br>
But when I refine the model in Phenix, Phenix treated the &quot;ATP&#39; as a monomer and didn&#39;t connect it to the downstream base.<br>
<br>
I tried two ways to solve it<br>
<br>
1. Add the the modified  (chang the &quot;_chem_comp.group&quot; option to &quot;RNA&quot;) 
cif file in phenix_refine, but Phenix doesn&#39;t recognize it. <br>
2. In REEL, I found phenix has its own cif file for ATP, but the its header couldn&#39;t be edited.<br>
<br>
Any suggestions?<br>
Thanks.<br>
<br>
<br>
Yu<br>
<br> <br>