View source for 4zsf


==Crystal structure of pre-specific restriction endonuclease BsaWI-DNA complex==
<StructureSection load='4zsf' size='340' side='right'caption='[[4zsf]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4zsf]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Geobacillus_stearothermophilus Geobacillus stearothermophilus] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ZSF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4ZSF 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]] 1.8&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=SIN:SUCCINIC+ACID'>SIN</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=4zsf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4zsf OCA], [https://pdbe.org/4zsf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4zsf RCSB], [https://www.ebi.ac.uk/pdbsum/4zsf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4zsf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q6UQ65_GEOSE Q6UQ65_GEOSE] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Type II restriction endonuclease BsaWI recognizes a degenerated sequence 5'-W/CCGGW-3' (W stands for A or T, '/' denotes the cleavage site). It belongs to a large family of restriction enzymes that contain a conserved CCGG tetranucleotide in their target sites. These enzymes are arranged as dimers or tetramers, and require binding of one, two or three DNA targets for their optimal catalytic activity. Here, we present a crystal structure and biochemical characterization of the restriction endonuclease BsaWI. BsaWI is arranged as an 'open' configuration dimer and binds a single DNA copy through a minor groove contacts. In the crystal primary BsaWI dimers form an indefinite linear chain via the C-terminal domain contacts implying possible higher order aggregates. We show that in solution BsaWI protein exists in a dimer-tetramer-oligomer equilibrium, but in the presence of specific DNA forms a tetramer bound to two target sites. Site-directed mutagenesis and kinetic experiments show that BsaWI is active as a tetramer and requires two target sites for optimal activity. We propose BsaWI mechanism that shares common features both with dimeric Ecl18kI/SgrAI and bona fide tetrameric NgoMIV/SfiI enzymes.

Functional significance of protein assemblies predicted by the crystal structure of the restriction endonuclease BsaWI.,Tamulaitis G, Rutkauskas M, Zaremba M, Grazulis S, Tamulaitiene G, Siksnys V Nucleic Acids Res. 2015 Sep 18;43(16):8100-10. doi: 10.1093/nar/gkv768. Epub 2015, Aug 3. PMID:26240380<ref>PMID:26240380</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4zsf" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Geobacillus stearothermophilus]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Grazulis S]]
[[Category: Rutkauskas M]]
[[Category: Siksnys V]]
[[Category: Tamulaitiene G]]