View source for 1xsb


==Structure of the nudix enzyme AP4A hydrolase from homo sapiens (E63A mutant) in complex with ATP. No ATP restraints included==
<StructureSection load='1xsb' size='340' side='right'caption='[[1xsb]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1xsb]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XSB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1XSB FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=1xsb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xsb OCA], [https://pdbe.org/1xsb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1xsb RCSB], [https://www.ebi.ac.uk/pdbsum/1xsb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1xsb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/AP4A_HUMAN AP4A_HUMAN] Asymmetrically hydrolyzes Ap4A to yield AMP and ATP. Plays a major role in maintaining homeostasis.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/xs/1xsb_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1xsb ConSurf].
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== Publication Abstract from PubMed ==
Asymmetric diadenosine 5',5'''-P(1),P(4)-tetraphosphate (Ap(4)A) hydrolases play a major role in maintaining homeostasis by cleaving the metabolite diadenosine tetraphosphate (Ap(4)A) back into ATP and AMP. The NMR solution structures of the 17-kDa human asymmetric Ap(4)A hydrolase have been solved in both the presence and absence of the product ATP. The adenine moiety of the nucleotide predominantly binds in a ring stacking arrangement equivalent to that observed in the x-ray structure of the homologue from Caenorhabditis elegans. The binding site is, however, markedly divergent to that observed in the plant/pathogenic bacteria class of enzymes, opening avenues for the exploration of specific therapeutics. Binding of ATP induces substantial conformational and dynamic changes that were not observed in the C. elegans structure. In contrast to the C. elegans homologue, important side chains that play a major role in substrate binding do not have to reorient to accommodate the ligand. This may have important implications in the mechanism of substrate recognition in this class of enzymes.

Structure and substrate-binding mechanism of human Ap4A hydrolase.,Swarbrick JD, Buyya S, Gunawardana D, Gayler KR, McLennan AG, Gooley PR J Biol Chem. 2005 Mar 4;280(9):8471-81. Epub 2004 Dec 13. PMID:15596429<ref>PMID:15596429</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Buyya S]]
[[Category: Gayler KR]]
[[Category: Gooley PR]]
[[Category: Gunawardana D]]
[[Category: McLennan AG]]
[[Category: Swarbrick JD]]