2aoq: Difference between revisions

New page: left|200px<br /><applet load="2aoq" size="450" color="white" frame="true" align="right" spinBox="true" caption="2aoq, resolution 2.20Å" /> '''Crystal structure of...
 
No edit summary
 
(13 intermediate revisions by the same user not shown)
Line 1: Line 1:
[[Image:2aoq.gif|left|200px]]<br /><applet load="2aoq" size="450" color="white" frame="true" align="right" spinBox="true"
caption="2aoq, resolution 2.20&Aring;" />
'''Crystal structure of MutH-unmethylated DNA complex'''<br />


==Overview==
==Crystal structure of MutH-unmethylated DNA complex==
MutH initiates mismatch repair by nicking the transiently unmethylated, daughter strand 5' to a GATC sequence. Here, we report crystal structures, of MutH complexed with hemimethylated and unmethylated GATC substrates., Both structures contain two Ca2+ ions jointly coordinated by a conserved, aspartate and the scissile phosphate, as observed in the restriction, endonucleases BamHI and BglI. In the hemimethylated complexes, the active, site is more compact and DNA cleavage is more efficient. The Lys residue, in the conserved DEK motif coordinates the nucleophilic water in, conjunction with the phosphate 3' to the scissile bond; the same Lys is, also hydrogen bonded with a carbonyl oxygen in the DNA binding module. We, propose that this Lys, which is conserved in many restriction, endonucleases and is replaced by Glu or Gln in BamHI and BglII, is a, sensor for DNA binding and the linchpin that couples base recognition and, DNA cleavage.
<StructureSection load='2aoq' size='340' side='right'caption='[[2aoq]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2aoq]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Haemophilus_influenzae Haemophilus influenzae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AOQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2AOQ 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</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=2aoq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aoq OCA], [https://pdbe.org/2aoq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2aoq RCSB], [https://www.ebi.ac.uk/pdbsum/2aoq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2aoq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MUTH_HAEIN MUTH_HAEIN] Sequence-specific endonuclease that cleaves unmethylated GATC sequences. It is involved in DNA mismatch repair (By similarity).
== 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/ao/2aoq_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=2aoq ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
MutH initiates mismatch repair by nicking the transiently unmethylated daughter strand 5' to a GATC sequence. Here, we report crystal structures of MutH complexed with hemimethylated and unmethylated GATC substrates. Both structures contain two Ca2+ ions jointly coordinated by a conserved aspartate and the scissile phosphate, as observed in the restriction endonucleases BamHI and BglI. In the hemimethylated complexes, the active site is more compact and DNA cleavage is more efficient. The Lys residue in the conserved DEK motif coordinates the nucleophilic water in conjunction with the phosphate 3' to the scissile bond; the same Lys is also hydrogen bonded with a carbonyl oxygen in the DNA binding module. We propose that this Lys, which is conserved in many restriction endonucleases and is replaced by Glu or Gln in BamHI and BglII, is a sensor for DNA binding and the linchpin that couples base recognition and DNA cleavage.


==About this Structure==
MutH complexed with hemi- and unmethylated DNAs: coupling base recognition and DNA cleavage.,Lee JY, Chang J, Joseph N, Ghirlando R, Rao DN, Yang W Mol Cell. 2005 Oct 7;20(1):155-66. PMID:16209953<ref>PMID:16209953</ref>
2AOQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Haemophilus_influenzae Haemophilus influenzae] with CA as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2AOQ OCA].


==Reference==
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
MutH complexed with hemi- and unmethylated DNAs: coupling base recognition and DNA cleavage., Lee JY, Chang J, Joseph N, Ghirlando R, Rao DN, Yang W, Mol Cell. 2005 Oct 7;20(1):155-66. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16209953 16209953]
</div>
<div class="pdbe-citations 2aoq" style="background-color:#fffaf0;"></div>
 
==See Also==
*[[DNA mismatch repair protein 3D structures|DNA mismatch repair protein 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Haemophilus influenzae]]
[[Category: Haemophilus influenzae]]
[[Category: Single protein]]
[[Category: Large Structures]]
[[Category: Chang, J.]]
[[Category: Chang J]]
[[Category: Ghirlando, R.]]
[[Category: Ghirlando R]]
[[Category: Joseph, N.]]
[[Category: Joseph N]]
[[Category: Lee, J.Y.]]
[[Category: Lee JY]]
[[Category: Rao, D.N.]]
[[Category: Rao DN]]
[[Category: Yang, W.]]
[[Category: Yang W]]
[[Category: CA]]
[[Category: gatc recognition]]
 
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 08:15:38 2007''

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA