View source for 5mcn


==Radiation damage to GH7 Family Cellobiohydrolase from Daphnia pulex: Dose (DWD) 22.7 MGy==
<StructureSection load='5mcn' size='340' side='right'caption='[[5mcn]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5mcn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Daphnia_pulex Daphnia pulex]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5MCN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5MCN FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=5mcn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5mcn OCA], [https://pdbe.org/5mcn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5mcn RCSB], [https://www.ebi.ac.uk/pdbsum/5mcn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5mcn ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/E9G5J5_DAPPU E9G5J5_DAPPU] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
During macromolecular X-ray crystallography experiments, protein crystals held at 100 K have been widely reported to exhibit reproducible bond scission events at doses on the order of several MGy. With the objective to mitigate the impact of radiation damage events on valid structure determination, it is essential to correctly understand the radiation chemistry mechanisms at play. OH-cleavage from tyrosine residues is regularly cited as amongst the most available damage pathways in protein crystals at 100 K, despite a lack of widespread reports of this phenomenon in protein crystal radiation damage studies. Furthermore, no clear mechanism for phenolic C-O bond cleavage in tyrosine has been reported, with the tyrosyl radical known to be relatively robust and long-lived in both aqueous solutions and the solid state. Here, the initial findings of Tyr -OH group damage in a myrosinase protein crystal have been reviewed. Consistent with that study, at increasing doses, clear electron density loss was detectable local to Tyr -OH groups. A systematic investigation performed on a range of protein crystal damage series deposited in the Protein Data Bank has established that Tyr -OH electron density loss is not generally a dominant damage pathway in protein crystals at 100 K. Full Tyr aromatic ring displacement is here proposed to account for instances of observable Tyr -OH electron density loss, with the original myrosinase data shown to be consistent with such a damage model. Systematic analysis of the effects of other environmental factors, including solvent accessibility and proximity to disulfide bonds or hydrogen bond interactions, is also presented. Residues in known active sites showed enhanced sensitivity to radiation-induced disordering, as has previously been reported.

OH cleavage from tyrosine: debunking a myth.,Bury CS, Carmichael I, Garman EF J Synchrotron Radiat. 2017 Jan 1;24(Pt 1):7-18. doi: 10.1107/S1600577516016775., Epub 2017 Jan 1. PMID:28009542<ref>PMID:28009542</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5mcn" style="background-color:#fffaf0;"></div>

==See Also==
*[[Cellobiohydrolase 3D structures|Cellobiohydrolase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Daphnia pulex]]
[[Category: Large Structures]]
[[Category: Bury CS]]
[[Category: Ebrahim A]]
[[Category: Garman EF]]
[[Category: McGeehan JE]]