View source for 1ssp


==WILD-TYPE URACIL-DNA GLYCOSYLASE BOUND TO URACIL-CONTAINING DNA==
<StructureSection load='1ssp' size='340' side='right'caption='[[1ssp]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ssp]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SSP OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1SSP 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ORP:2-DEOXY-5-PHOSPHONO-RIBOSE'>ORP</scene>, <scene name='pdbligand=URA:URACIL'>URA</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=1ssp FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ssp OCA], [https://pdbe.org/1ssp PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ssp RCSB], [https://www.ebi.ac.uk/pdbsum/1ssp PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ssp ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/UNG_HUMAN UNG_HUMAN] Defects in UNG are a cause of immunodeficiency with hyper-IgM type 5 (HIGM5) [MIM:[https://omim.org/entry/608106 608106]. A rare immunodeficiency syndrome characterized by normal or elevated serum IgM levels with absence of IgG, IgA, and IgE. It results in a profound susceptibility to bacterial infections.<ref>PMID:12958596</ref> <ref>PMID:15967827</ref> 
== Function ==
[https://www.uniprot.org/uniprot/UNG_HUMAN UNG_HUMAN] Excises uracil residues from the DNA which can arise as a result of misincorporation of dUMP residues by DNA polymerase or due to deamination of cytosine.
== 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/ss/1ssp_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=1ssp ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
Three high-resolution crystal structures of DNA complexes with wild-type and mutant human uracil-DNA glycosylase (UDG), coupled kinetic characterizations and comparisons with the refined unbound UDG structure help resolve fundamental issues in the initiation of DNA base excision repair (BER): damage detection, nucleotide flipping versus extrahelical nucleotide capture, avoidance of apurinic/apyrimidinic (AP) site toxicity and coupling of damage-specific and damage-general BER steps. Structural and kinetic results suggest that UDG binds, kinks and compresses the DNA backbone with a 'Ser-Pro pinch' and scans the minor groove for damage. Concerted shifts in UDG simultaneously form the catalytically competent active site and induce further compression and kinking of the double-stranded DNA backbone only at uracil and AP sites, where these nucleotides can flip at the phosphate-sugar junction into a complementary specificity pocket. Unexpectedly, UDG binds to AP sites more tightly and more rapidly than to uracil-containing DNA, and thus may protect cells sterically from AP site toxicity. Furthermore, AP-endonuclease, which catalyzes the first damage-general step of BER, enhances UDG activity, most likely by inducing UDG release via shared minor groove contacts and flipped AP site binding. Thus, AP site binding may couple damage-specific and damage-general steps of BER without requiring direct protein-protein interactions.

Base excision repair initiation revealed by crystal structures and binding kinetics of human uracil-DNA glycosylase with DNA.,Parikh SS, Mol CD, Slupphaug G, Bharati S, Krokan HE, Tainer JA EMBO J. 1998 Sep 1;17(17):5214-26. PMID:9724657<ref>PMID:9724657</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1ssp" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA glycosylase 3D structures|DNA glycosylase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Bharati S]]
[[Category: Krokan HE]]
[[Category: Mol CD]]
[[Category: Parikh SS]]
[[Category: Slupphaug G]]
[[Category: Tainer JA]]