View source for 2idq


==Structure of M98A mutant of amicyanin, Cu(II)==
<StructureSection load='2idq' size='340' side='right'caption='[[2idq]], [[Resolution|resolution]] 0.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2idq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Paracoccus_denitrificans Paracoccus denitrificans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2IDQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2IDQ 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]] 0.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CU:COPPER+(II)+ION'>CU</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=2idq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2idq OCA], [https://pdbe.org/2idq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2idq RCSB], [https://www.ebi.ac.uk/pdbsum/2idq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2idq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/AMCY_PARDE AMCY_PARDE] Primary acceptor of electrons from methylamine dehydrogenase. Passes those electrons on either a soluble cytochrome c or to pseudoazurin.
== 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/id/2idq_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=2idq ConSurf].
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== Publication Abstract from PubMed ==
Amicyanin from Paracoccus denitrificans is a type 1 copper protein with three strong equatorial copper ligands provided by nitrogens of His53 and His95 and the sulfur of Cys92, with an additional weak axial ligand provided by the sulfur of Met98. Met98 was replaced with either Gln or Ala. As isolated, the M98A and M98Q mutant proteins contain zinc in the active site. The zinc is then removed and replaced with copper so that the copper-containing proteins may be studied. Each of the mutant amicyanins exhibits a marked decrease in thermal stability relative to that of native amicyanin, consistent with the weaker affinity for copper. Crystal structures were obtained for the oxidized and reduced forms of M98A and M98Q amicyanins at atomic resolution (&lt;or=1.0 A). The crystal structure of oxidized M98A amicyanin exhibits a type 1 ligation geometry but with the axial ligand provided by a water, which fills the void left by the mutation of Met to Ala. The protein undergoes a reversible switch in ligation geometry when going from the aqueous to the frozen state. The visible absorption spectrum in solution is characteristic of type 1 copper, consistent with the crystal structure. On freezing, the blue color is lost, and EPR spectroscopy reveals that the copper is primarily type 2. The crystal structure of reduced M98A amicyanin exhibits an unprecedented ligation geometry in which the His95-Cu coordination is broken, and copper is left with only two ligands from His53 and Cys92 in an almost linear coordination. The replacement of Met98 with Gln yielded a type 1 copper site with increased rhombicity evident from its EPR and visible absorption spectra, and an increase in distance from Cu to the trigonal equatorial plane seen in the crystal structure. Gln98 coordinates more strongly with copper than Met, and the oxidized and reduced forms each exhibit two alternate conformers. EPR and metal analysis of oxidized M98Q amicyanin indicate that a small population of the protein contains weakly bound type 2 copper, which may be removed by washing with EDTA. These results demonstrate that the identity as well as position and rigidity of the axial ligand of the type 1 copper site has a profound influence in the uptake specificity of metal ions, protein stability, and determination of the active site geometry and its spectroscopic properties.

Generation of novel copper sites by mutation of the axial ligand of amicyanin. Atomic resolution structures and spectroscopic properties.,Carrell CJ, Ma JK, Antholine WE, Hosler JP, Mathews FS, Davidson VL Biochemistry. 2007 Feb 20;46(7):1900-12. PMID:17295442<ref>PMID:17295442</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Amicyanin 3D structures|Amicyanin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Paracoccus denitrificans]]
[[Category: Antholine W]]
[[Category: Carrell CJ]]
[[Category: Davidson VL]]
[[Category: Hosler JP]]
[[Category: Ma JK]]
[[Category: Mathews FS]]