View source for 1amk


==LEISHMANIA MEXICANA TRIOSE PHOSPHATE ISOMERASE==
<StructureSection load='1amk' size='340' side='right'caption='[[1amk]], [[Resolution|resolution]] 1.83&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1amk]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Leishmania_mexicana Leishmania mexicana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AMK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1AMK 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]] 1.83&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PGA:2-PHOSPHOGLYCOLIC+ACID'>PGA</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=1amk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1amk OCA], [https://pdbe.org/1amk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1amk RCSB], [https://www.ebi.ac.uk/pdbsum/1amk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1amk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TPIS_LEIME TPIS_LEIME] 
== 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/am/1amk_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=1amk ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The dimeric enzyme triosephosphate isomerase (TIM) has a very tight and rigid dimer interface. At this interface a critical hydrogen bond is formed between the main chain oxygen atom of the catalytic residue Lys13 and the completely buried side chain of Gln65 (of the same subunit). The sequence of Leishmania mexicana TIM, closely related to Trypanosoma brucei TIM (68% sequence identity), shows that this highly conserved glutamine has been replaced by a glutamate. Therefore, the 1.8 A crystal structure of leishmania TIM (at pH 5.9) was determined. The comparison with the structure of trypanosomal TIM shows no rearrangements in the vicinity of Glu65, suggesting that its side chain is protonated and is hydrogen bonded to the main chain oxygen of Lys13. Ionization of this glutamic acid side chain causes a pH-dependent decrease in the thermal stability of leishmania TIM. The presence of this glutamate, also in its protonated state, disrupts to some extent the conserved hydrogen bond network, as seen in all other TIMs. Restoration of the hydrogen bonding network by its mutation to glutamine in the E65Q variant of leishmania TIM results in much higher stability; for example, at pH 7, the apparent melting temperature increases by 26 degrees C (57 degrees C for leishmania TIM to 83 degrees C for the E65Q variant). This mutation does not affect the kinetic properties, showing that even point mutations can convert a mesophilic enzyme into a superstable enzyme without losing catalytic power at the mesophilic temperature.

Structural and mutagenesis studies of leishmania triosephosphate isomerase: a point mutation can convert a mesophilic enzyme into a superstable enzyme without losing catalytic power.,Williams JC, Zeelen JP, Neubauer G, Vriend G, Backmann J, Michels PA, Lambeir AM, Wierenga RK Protein Eng. 1999 Mar;12(3):243-50. PMID:10235625<ref>PMID:10235625</ref>

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

==See Also==
*[[Triose phosphate isomerase 3D structures|Triose phosphate isomerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Leishmania mexicana]]
[[Category: Wierenga R]]
[[Category: Williams JC]]