View source for 1nnj


==Crystal structure Complex between the Lactococcus lactis Fpg and an abasic site containing DNA==
<StructureSection load='1nnj' size='340' side='right'caption='[[1nnj]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1nnj]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Lactococcus_lactis Lactococcus lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NNJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NNJ 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=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=PDI:PHOSPHORIC+ACID+MONO-(3-HYDROXY-PROPYL)+ESTER'>PDI</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=1nnj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nnj OCA], [https://pdbe.org/1nnj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1nnj RCSB], [https://www.ebi.ac.uk/pdbsum/1nnj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1nnj ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/FPG_LACLC FPG_LACLC] Involved in base excision repair of DNA damaged by oxidation or by mutagenic agents. Acts as DNA glycosylase that recognizes and removes damaged bases. Has a preference for oxidized purines, such as 7,8-dihydro-8-oxoguanine (8-oxoG). Has AP (apurinic/apyrimidinic) lyase activity and introduces nicks in the DNA strand. Cleaves the DNA backbone by beta-delta elimination to generate a single-strand break at the site of the removed base with both 3'- and 5'-phosphates.<ref>PMID:7704272</ref> 
== 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/nn/1nnj_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=1nnj ConSurf].
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== Publication Abstract from PubMed ==
Fpg is a DNA glycosylase that recognizes and excises the mutagenic 8-oxoguanine (8-oxoG) and the potentially lethal formamidopyrimidic residues (Fapy). Fpg is also associated with an AP lyase activity which successively cleaves the abasic (AP) site at the 3' and 5' sides by betadelta-elimination. Here, we present the high-resolution crystal structures of the wild-type and the P1G defective mutant of Fpg from Lactococcus lactis bound to 14mer DNA duplexes containing either a tetrahydrofuran (THF) or 1,3-propanediol (Pr) AP site analogues. Structures show that THF is less extrahelical than Pr and its backbone C5'-C4'-C3' diverges significantly from those of Pr, rAP, 8-oxodG and FapydG. Clearly, the heterocyclic oxygen of THF is pushed back by the carboxylate of the strictly conserved E2 residue. We can propose that the ring-opened form of the damaged deoxyribose is the structure active form of the sugar for Fpg catalysis process. Both structural and functional data suggest that the first step of catalysis mediated by Fpg involves the expulsion of the O4' leaving group facilitated by general acid catalysis (involving E2), rather than the immediate cleavage of the N-glycosic bond of the damaged nucleoside.

Structural insights into abasic site for Fpg specific binding and catalysis: comparative high-resolution crystallographic studies of Fpg bound to various models of abasic site analogues-containing DNA.,Pereira de Jesus K, Serre L, Zelwer C, Castaing B Nucleic Acids Res. 2005 Oct 20;33(18):5936-44. Print 2005. PMID:16243784<ref>PMID:16243784</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 1nnj" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA glycosylase 3D structures|DNA glycosylase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Lactococcus lactis]]
[[Category: Large Structures]]
[[Category: Boiteux S]]
[[Category: Castaing B]]
[[Category: Pereira de Jesus K]]
[[Category: Serre L]]
[[Category: Zelwer C]]