<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">To follow up to Elaine's reply, Antechamber does not handle metals well. I will try to get Chimera to notice when a residue is a metal-coordination complex and ask for the metal/non-metal formal charges separately, and only send the non-metal part off to Antechamber. So for now Elaine's suggestion of temporarily deleting the metal is probably the best workaround.<DIV><BR class="khtml-block-placeholder"></DIV><DIV>On top of this problem, there is a bug in Antechamber where it identifies the iron as fluorine, since it only treats atom names that start with 'Fe' as iron (not 'FE'!). Since Antechamber determines the number of electrons by adding up the atomic numbers + formal charge, that's why it is only working with odd formal charges (iron's atomic number is 26; fluorine's is 9).</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>--Eric</DIV><DIV><DIV><BR><DIV> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="5" style="font: 16.0px Helvetica"><SPAN class="Apple-converted-space"> </SPAN>Eric Pettersen</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="5" style="font: 16.0px Helvetica"><SPAN class="Apple-converted-space"> </SPAN>UCSF Computer Graphics Lab</FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="5" style="font: 16.0px Helvetica"><SPAN class="Apple-converted-space"> </SPAN><A href="mailto:pett@cgl.ucsf.edu">pett@cgl.ucsf.edu</A></FONT></P> <P style="margin: 0.0px 0.0px 0.0px 0.0px"><FONT face="Helvetica" size="5" style="font: 16.0px Helvetica"><SPAN class="Apple-converted-space"> </SPAN><A href="http://www.cgl.ucsf.edu">http://www.cgl.ucsf.edu</A></FONT></P> <BR class="Apple-interchange-newline"> </DIV><BR><DIV><DIV>On Jun 4, 2007, at 10:24 AM, Elaine Meng wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Hello,</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Yes, you can have Fe(II) in Chimera.<SPAN class="Apple-converted-space"> </SPAN>I am guessing that in your <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">structure, the Fe ion is part of the residue named HEM. In this case <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">(using PDB entry 1a6m as my example), addcharge fails if you set the <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">net charge to an even number. The HEM residue in 1a6m is <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">protoporphyrin IX and iron, where (I think) the protoporphyrin IX has <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">a net charge of -4.<SPAN class="Apple-converted-space"> </SPAN>So if you wanted Fe(II), the net charge would be <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-2, which leads to an error message and Antechamber failure.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">The problem is that what the PDB thinks is one residue is more <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">appropriately treated as two separate residues for charge <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">calculation.<SPAN class="Apple-converted-space"> </SPAN>Chimera tries to do everything for you and just treats <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">each residue as a molecule, but in this case it should be two <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">separate molecules.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I recommend editing the PDB file in a text editor to change the <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">residue name of the Fe atom to something else so it will be perceived <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">as a separate residue.<SPAN class="Apple-converted-space"> </SPAN>In the case of 1a6m, I changed the residue <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">name of the Fe atom to FE2, re-opened the structure, added hydrogens, <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">and then in the addcharge dialog, I used +2 as the formal charge of <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">the FE2 residue and -4 as the formal charge of the HEM residue (the <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">original HEM minus the FE atom).</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Another possible approach would be to just delete the FE (after <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">hydrogen addition so you don't get unwanted hydrogens on the <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">porphyrin part), calculate charges, and then edit the FE atom back in <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">to the resulting PDB file.<SPAN class="Apple-converted-space"> </SPAN>You could then put the +2 charge on the <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">FE with the "setattr" command or just edit that charge into an output <SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Mol2 file, if the purpose was to create such a file.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I hope this helps,</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Elaine</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-----</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Elaine C. Meng, Ph.D.<SPAN class="Apple-converted-space"> </SPAN><A href="mailto:meng@cgl.ucsf.edu">meng@cgl.ucsf.edu</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">UCSF Computer Graphics Lab and Babbitt Lab</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Department of Pharmaceutical Chemistry</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">University of California, San Francisco</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN><A href="http://www.cgl.ucsf.edu/home/meng/index.html">http://www.cgl.ucsf.edu/home/meng/index.html</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">On Jun 4, 2007, at 5:08 AM, Газизов А.С. wrote:</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Hello everybody.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Is there Fe2+ ion in Chimera? I'm trying to add charges to hem</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">molecule and it always appears to be Fe3+ (and Add Charge tool</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">reports "There is odd number of electrons..." and fails).Assigning</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">odd overall charge helps (i.e. +1, +3, etc), but I need +2...</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Chimera-users mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:Chimera-users@cgl.ucsf.edu">Chimera-users@cgl.ucsf.edu</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users">http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> </BLOCKQUOTE></DIV><BR></DIV></DIV></BODY></HTML>