View source for 4ba2


==Archaeal exosome (Rrp4-Rrp41(D182A)-Rrp42) bound to inorganic phosphate==
<StructureSection load='4ba2' size='340' side='right'caption='[[4ba2]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4ba2]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharolobus_solfataricus Saccharolobus solfataricus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4BA2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4BA2 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]] 2.501&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1PE:PENTAETHYLENE+GLYCOL'>1PE</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=4ba2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ba2 OCA], [https://pdbe.org/4ba2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ba2 RCSB], [https://www.ebi.ac.uk/pdbsum/4ba2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ba2 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RRP41_SACS2 RRP41_SACS2] Catalytic component of the exosome, which is a complex involved in RNA degradation. Has 3'->5' exoribonuclease activity. Can also synthesize heteromeric RNA-tails. Binds RNA.[HAMAP-Rule:MF_00591]<ref>PMID:15951817</ref> <ref>PMID:17380186</ref> <ref>PMID:20488184</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The RNA exosome is an important protein complex that functions in the 3' processing and degradation of RNA in archaeal and eukaryotic organisms. The archaeal exosome is functionally similar to bacterial polynucleotide phosphorylase (PNPase) and RNase PH enzymes as it uses inorganic phosphate (Pi) to processively cleave RNA substrates releasing nucleoside diphosphates. To shed light on the mechanism of catalysis, we have determined the crystal structures of mutant archaeal exosome in complex with either Pi or with both RNA and Pi at resolutions of 1.8 A and 2.5 A, respectively. These structures represent views of precatalytic states of the enzyme and allow the accurate determination of the substrate binding geometries. In the structure with both Pi and RNA bound, the Pi closely approaches the phosphate of the 3'-end nucleotide of the RNA and is in a perfect position to perform a nucleophilic attack. The presence of negative charge resulting from the close contacts between the phosphates appears to be neutralized by conserved positively charged residues in the active site of the archaeal exosome. The high degree of structural conservation between the archaeal exosome and the PNPase including the requirement for divalent metal ions for catalysis is discussed.

Crystal structure of a 9-subunit archaeal exosome in pre-catalytic States of the phosphorolytic reaction.,Lorentzen E, Conti E Archaea. 2012;2012:721869. doi: 10.1155/2012/721869. Epub 2012 Dec 20. PMID:23319881<ref>PMID:23319881</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4ba2" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharolobus solfataricus]]
[[Category: Conti E]]
[[Category: Lorentzen E]]