View source for 4ktz


==Lactococcus phage 67 RuvC==
<StructureSection load='4ktz' size='340' side='right'caption='[[4ktz]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4ktz]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Lactococcus_virus_bIL67 Lactococcus virus bIL67]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4KTZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4KTZ 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=4ktz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ktz OCA], [https://pdbe.org/4ktz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ktz RCSB], [https://www.ebi.ac.uk/pdbsum/4ktz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ktz ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q38242_9CAUD Q38242_9CAUD] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Viral and bacterial Holliday junction resolvases differ in specificity with the former typically being more promiscuous, acting on a variety of branched DNA substrates, while the latter exclusively targets Holliday junctions. We have determined the crystal structure of a RuvC resolvase from bacteriophage bIL67 to help identify features responsible for DNA branch discrimination. Comparisons between phage and bacterial RuvC structures revealed significant differences in the number and position of positively-charged residues in the outer sides of the junction binding cleft. Substitutions were generated in phage RuvC residues implicated in branch recognition and six were found to confer defects in Holliday junction and replication fork cleavage in vivo. Two mutants, R121A and R124A that flank the DNA binding site were purified and exhibited reduced in vitro binding to fork and linear duplex substrates relative to the wild-type, while retaining the ability to bind X junctions. Crucially, these two variants cleaved Holliday junctions with enhanced specificity and symmetry, a feature more akin to cellular RuvC resolvases. Thus, additional positive charges in the phage RuvC binding site apparently stabilize productive interactions with branched structures other than the canonical Holliday junction, a feature advantageous for viral DNA processing but deleterious for their cellular counterparts.

Mutants of phage bIL67 RuvC with enhanced Holliday junction binding selectivity and resolution symmetry.,Green V, Curtis FA, Sedelnikova S, Rafferty JB, Sharples GJ Mol Microbiol. 2013 Jul 25. doi: 10.1111/mmi.12343. PMID:23888987<ref>PMID:23888987</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4ktz" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Lactococcus virus bIL67]]
[[Category: Large Structures]]
[[Category: Green V]]
[[Category: Rafferty JB]]