View source for 4i5o


==Crystal Structure of W-W-R ClpX Hexamer==
<StructureSection load='4i5o' size='340' side='right'caption='[[4i5o]], [[Resolution|resolution]] 4.48&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4i5o]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4I5O OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4I5O 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]] 4.4787&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=4i5o FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4i5o OCA], [https://pdbe.org/4i5o PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4i5o RCSB], [https://www.ebi.ac.uk/pdbsum/4i5o PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4i5o ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CLPX_ECOLI CLPX_ECOLI] ATP-dependent specificity component of the Clp protease. It directs the protease to specific substrates. It may bind to the lambda O substrate protein and present it to the ClpP protease in a form that can be recognized and readily hydrolyzed by ClpP. Can perform chaperone functions in the absence of ClpP.[HAMAP-Rule:MF_00175]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
ClpX, a AAA+ ring homohexamer, uses the energy of ATP binding and hydrolysis to power conformational changes that unfold and translocate target proteins into the ClpP peptidase for degradation. In multiple crystal structures, some ClpX subunits adopt nucleotide-loadable conformations, others adopt unloadable conformations, and each conformational class exhibits substantial variability. Using mutagenesis of individual subunits in covalently tethered hexamers together with fluorescence methods to assay the conformations and nucleotide-binding properties of these subunits, we demonstrate that dynamic interconversion between loadable and unloadable conformations is required to couple ATP hydrolysis by ClpX to mechanical work. ATP binding to different classes of subunits initially drives staged allosteric changes, which set the conformation of the ring to allow hydrolysis and linked mechanical steps. Subunit switching between loadable and unloadable conformations subsequently isomerizes or resets the configuration of the nucleotide-loaded ring and is required for mechanical function.

Nucleotide Binding and Conformational Switching in the Hexameric Ring of a AAA+ Machine.,Stinson BM, Nager AR, Glynn SE, Schmitz KR, Baker TA, Sauer RT Cell. 2013 Apr 25;153(3):628-39. doi: 10.1016/j.cell.2013.03.029. PMID:23622246<ref>PMID:23622246</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4i5o" style="background-color:#fffaf0;"></div>

==See Also==
*[[Clp protease 3D structures|Clp protease 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Baker TA]]
[[Category: Glynn SE]]
[[Category: Nager AR]]
[[Category: Sauer RT]]
[[Category: Schmitz KR]]
[[Category: Stinson BS]]