View source for 3krg


==Structural insights into substrate specificity and the anti beta-elimination mechanism of pectate lyase==
<StructureSection load='3krg' size='340' side='right'caption='[[3krg]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3krg]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3KRG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3KRG 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=ADA:ALPHA-D-GALACTOPYRANURONIC+ACID'>ADA</scene>, <scene name='pdbligand=CO:COBALT+(II)+ION'>CO</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</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=3krg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3krg OCA], [https://pdbe.org/3krg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3krg RCSB], [https://www.ebi.ac.uk/pdbsum/3krg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3krg ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PLY_BACSU PLY_BACSU] Produces unsaturated products from polygalacturonate.
== 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/kr/3krg_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=3krg ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Pectate lyases harness anti beta-elimination chemistry to cleave the alpha-1,4 linkage in the homogalacturonan region of plant cell wall pectin. We have studied the binding of five pectic oligosaccharides to Bacillus subtilis pectate lyase in crystals of the inactive enzyme in which the catalytic base is substituted with alanine (R279A). We discover that the three central subsites (-1, +1, and +2) have a profound preference for galacturonate but that the distal subsites can accommodate methylated galacturonate. It is reasonable to assume therefore that pectate lyase can cleave pectin with three consecutive galacturonate residues. The enzyme in the absence of substrate binds a single calcium ion, and we show that two additional calcium ions bind between enzyme and substrate carboxylates occupying the +1 subsite in the Michaelis complex. The substrate binds less intimately to the enzyme in a complex made with a catalytic base in place but in the absence of the calcium ions and an adjacent lysine. In this complex, the catalytic base is correctly positioned to abstract the C5 proton, but there are no calcium ions binding the carboxylate at the +1 subsite. It is clear, therefore, that the catalytic calcium ions and adjacent lysine promote catalysis by acidifying the alpha-proton, facilitating its abstraction by the base. There is also clear evidence that binding distorts the relaxed 2(1) or 3(1) helical conformation of the oligosaccharides in the region of the scissile bond.

Structural insights into substrate specificity and the anti beta-elimination mechanism of pectate lyase.,Seyedarabi A, To TT, Ali S, Hussain S, Fries M, Madsen R, Clausen MH, Teixteira S, Brocklehurst K, Pickersgill RW Biochemistry. 2010 Jan 26;49(3):539-46. PMID:20000851<ref>PMID:20000851</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3krg" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bacillus subtilis]]
[[Category: Large Structures]]
[[Category: Pickersgill RW]]
[[Category: To TT]]