View source for 5g4d


==Crystal structure of the Cas2 in T.onnurineus==
<StructureSection load='5g4d' size='340' side='right'caption='[[5g4d]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5g4d]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermococcus_onnurineus Thermococcus onnurineus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5G4D OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5G4D 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]] 1.701&#8491;</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=5g4d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5g4d OCA], [https://pdbe.org/5g4d PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5g4d RCSB], [https://www.ebi.ac.uk/pdbsum/5g4d PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5g4d ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/B6YTB8_THEON B6YTB8_THEON] CRISPR (clustered regularly interspaced short palindromic repeat), is an adaptive immune system that provides protection against mobile genetic elements (viruses, transposable elements and conjugative plasmids). CRISPR clusters contain sequences complementary to antecedent mobile elements and target invading nucleic acids. CRISPR clusters are transcribed and processed into CRISPR RNA (crRNA). Functions as a ssRNA-specific endoribonuclease. Involved in the integration of spacer DNA into the CRISPR cassette.[HAMAP-Rule:MF_01471]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
CRISPR-Cas is RNA-based prokaryotic immune systems that defend against exogenous genetic elements such as plasmids and viruses. Cas1 and Cas2 are highly conserved components that play an essential part in the adaptation stage of all CRISPR-Cas systems. Characterization of CRISPR-Cas genes in Thermococcus onnurineus reveals the association of the Cas2 gene with the putative type IV system that lacks Cas1 or its homologous genes. Here, we present a crystal structure of T. onnurineus Cas2 (Ton_Cas2) that exhibits a deep and wide cleft at an interface lined with positive residues (Arg16, Lys18, Lys19, Arg22, and Arg23). The obvious DNA recognizing loops in Cas2 from E. coli (Eco_Cas2) are absent in Ton_Cas2 and have significantly different shapes and electrostatic potential distributions around the putative nucleotide binding region. Furthermore, Ton_Cas2 lacks the hairpin motif at the C-terminus that is responsible for Cas1 binding in Eco_Cas2. These structural features could be a unique signature and indicate an altered functional mechanism in the adaptation stage of Cas2 in type IV CRISPR-Cas systems.

Structural features of Cas2 from Thermococcus onnurineus in CRISPR-cas system type IV.,Jung TY, Park KH, An Y, Schulga A, Deyev S, Jung JH, Woo EJ Protein Sci. 2016 Jul 12. doi: 10.1002/pro.2981. PMID:27400737<ref>PMID:27400737</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5g4d" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Thermococcus onnurineus]]
[[Category: Jung TY]]
[[Category: Park KH]]
[[Category: Woo EJ]]