5ds5: Difference between revisions
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==Crystal structure the Escherichia coli Cas1-Cas2 complex bound to protospacer DNA and Mg== | ==Crystal structure the Escherichia coli Cas1-Cas2 complex bound to protospacer DNA and Mg== | ||
<StructureSection load='5ds5' size='340' side='right' caption='[[5ds5]], [[Resolution|resolution]] 2.95Å' scene=''> | <StructureSection load='5ds5' size='340' side='right'caption='[[5ds5]], [[Resolution|resolution]] 2.95Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[5ds5]] is a 8 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5DS5 OCA]. For a <b>guided tour on the structure components</b> use [ | <table><tr><td colspan='2'>[[5ds5]] is a 8 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12] and [https://en.wikipedia.org/wiki/Escherichia_virus_M13 Escherichia virus M13]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5DS5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5DS5 FirstGlance]. <br> | ||
</td></tr><tr id=' | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.951Å</td></tr> | ||
<tr id=' | <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'>[ | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=5ds5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5ds5 OCA], [https://pdbe.org/5ds5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5ds5 RCSB], [https://www.ebi.ac.uk/pdbsum/5ds5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5ds5 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[ | [https://www.uniprot.org/uniprot/CAS1_ECOLI CAS1_ECOLI] 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). Cas1 is thought to be involved in CRISPR adaptation, the first stage of CRISPR immunity. Might be involved in the addition/removal of CRISPR spacers. Endonucleolytically cleaves linear ssRNA, ssDNA and short (34 base) dsDNA as well as branched DNA substrates such as Holliday junctions, replication forks and 5'-flap DNA substrates. Genetic interactions suggest Cas1 interacts with components of the RecBC and RuvB DNA repair systems.<ref>PMID:21255106</ref> | ||
<div style="background-color:#fffaf0;"> | <div style="background-color:#fffaf0;"> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
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</div> | </div> | ||
<div class="pdbe-citations 5ds5" style="background-color:#fffaf0;"></div> | <div class="pdbe-citations 5ds5" style="background-color:#fffaf0;"></div> | ||
==See Also== | |||
*[[Endonuclease 3D structures|Endonuclease 3D structures]] | |||
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: | [[Category: Escherichia coli K-12]] | ||
[[Category: Escherichia virus M13]] | |||
[[Category: Large Structures]] | |||
[[Category: Doudna JA]] | |||
[[Category: Engelman AN]] | |||
[[Category: | [[Category: Harrington LB]] | ||
[[Category: | [[Category: Kranzusch PJ]] | ||
[[Category: | [[Category: Nunez JK]] | ||
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Latest revision as of 00:57, 29 June 2023
Crystal structure the Escherichia coli Cas1-Cas2 complex bound to protospacer DNA and MgCrystal structure the Escherichia coli Cas1-Cas2 complex bound to protospacer DNA and Mg
Structural highlights
FunctionCAS1_ECOLI 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). Cas1 is thought to be involved in CRISPR adaptation, the first stage of CRISPR immunity. Might be involved in the addition/removal of CRISPR spacers. Endonucleolytically cleaves linear ssRNA, ssDNA and short (34 base) dsDNA as well as branched DNA substrates such as Holliday junctions, replication forks and 5'-flap DNA substrates. Genetic interactions suggest Cas1 interacts with components of the RecBC and RuvB DNA repair systems.[1] Publication Abstract from PubMedBacteria and archaea generate adaptive immunity against phages and plasmids by integrating foreign DNA of specific 30-40-base-pair lengths into clustered regularly interspaced short palindromic repeat (CRISPR) loci as spacer segments. The universally conserved Cas1-Cas2 integrase complex catalyses spacer acquisition using a direct nucleophilic integration mechanism similar to retroviral integrases and transposases. How the Cas1-Cas2 complex selects foreign DNA substrates for integration remains unknown. Here we present X-ray crystal structures of the Escherichia coli Cas1-Cas2 complex bound to cognate 33-nucleotide protospacer DNA substrates. The protein complex creates a curved binding surface spanning the length of the DNA and splays the ends of the protospacer to allow each terminal nucleophilic 3'-OH to enter a channel leading into the Cas1 active sites. Phosphodiester backbone interactions between the protospacer and the proteins explain the sequence-nonspecific substrate selection observed in vivo. Our results uncover the structural basis for foreign DNA capture and the mechanism by which Cas1-Cas2 functions as a molecular ruler to dictate the sequence architecture of CRISPR loci. Foreign DNA capture during CRISPR-Cas adaptive immunity.,Nunez JK, Harrington LB, Kranzusch PJ, Engelman AN, Doudna JA Nature. 2015 Nov 26;527(7579):535-8. doi: 10.1038/nature15760. Epub 2015 Oct 21. PMID:26503043[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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