View source for 6ljk


==Crystal structure of human Sirt5 in complex with an internally quenched fluorescent substrate GluIQF==
<StructureSection load='6ljk' size='340' side='right'caption='[[6ljk]], [[Resolution|resolution]] 1.39&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6ljk]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] 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=6LJK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6LJK 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]] 1.394&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BE2:2-AMINOBENZOIC+ACID'>BE2</scene>, <scene name='pdbligand=GUA:GLUTARIC+ACID'>GUA</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=NIY:META-NITRO-TYROSINE'>NIY</scene>, <scene name='pdbligand=SET:AMINOSERINE'>SET</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=6ljk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ljk OCA], [https://pdbe.org/6ljk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6ljk RCSB], [https://www.ebi.ac.uk/pdbsum/6ljk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6ljk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SIR5_HUMAN SIR5_HUMAN] NAD-dependent lysine demalonylase and desuccinylase that specifically removes malonyl and succinyl groups on target proteins. Activates CPS1 and contributes to the regulation of blood ammonia levels during prolonged fasting: acts by mediating desuccinylation of CPS1, thereby increasing CPS1 activity in response to elevated NAD levels during fasting. Activates SOD1 by mediating its desuccinylation, leading to reduced reactive oxygen species. Has weak NAD-dependent protein deacetylase activity; however this activity may not be physiologically relevant in vivo. Can deacetylate cytochrome c (CYCS) and a number of other proteins in vitro.<ref>PMID:18680753</ref> <ref>PMID:21908771</ref> <ref>PMID:24140062</ref> <ref>PMID:22076378</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Sirtuins (SIRTs) are NAD(+)-dependent lysine deacylases, regulating many important biological processes such as metabolism and stress responses. SIRT inhibitors may provide potential benefits against SIRT-driven human diseases. Development of efficient assay platforms based on fluorogenic substrates will facilitate the discovery of high-quality SIRT inhibitors. We here report 16 new fluorogenic peptide substrates (P1-P16) designed with structurally diverse tetrapeptides and acyl modifications. Tests of P1-P16 against SIRT isoforms identified several sensitive substrates for SIRT1, SIRT2, SIRT3 and SIRT5, which manifested lower KM values and higher catalytic efficiency, and particularly had less signal interference in inhibitor screening compared with our previously reported internally quenched fluorescent substrates. Co-crystallization of sensitive substrates P13 and P15 with SIRT5 revealed an unexpected binding mode, involving interactions with residues from active site bordering surfaces, different from that observed for other peptides derived from natural protein substrates. By using SIRT5 sensitive substrates, we found that TW-37, a Bcl-2 inhibitor, displayed low micromolar inhibition to SIRT5, which was further validated by isothermal titration calorimetry analyses, offering a new point to develop dual-action SIRT5/Bcl-2 inhibitors against cancers. This work provides assay platform and structural basis for developing new substrates and inhibitors targeting human SIRTs.

Sensitive fluorogenic substrates for sirtuin deacylase inhibitor discovery.,Yang LL, Wang HL, Yan YH, Liu S, Yu ZJ, Huang MY, Luo Y, Zheng X, Yu Y, Li GB Eur J Med Chem. 2020 Apr 15;192:112201. doi: 10.1016/j.ejmech.2020.112201. Epub, 2020 Mar 2. PMID:32163813<ref>PMID:32163813</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6ljk" style="background-color:#fffaf0;"></div>

==See Also==
*[[Histone deacetylase 3D structures|Histone deacetylase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Chen Q]]
[[Category: Yu Y]]