View source for 5tvm


==Crystal structure of Trypanosoma brucei AdoMetDC/prozyme heterodimer==
<StructureSection load='5tvm' size='340' side='right'caption='[[5tvm]], [[Resolution|resolution]] 2.41&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5tvm]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Trypanosoma_brucei_brucei_TREU927 Trypanosoma brucei brucei TREU927]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5TVM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5TVM 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]] 2.408&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=B3P:2-[3-(2-HYDROXY-1,1-DIHYDROXYMETHYL-ETHYLAMINO)-PROPYLAMINO]-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>B3P</scene>, <scene name='pdbligand=PUT:1,4-DIAMINOBUTANE'>PUT</scene>, <scene name='pdbligand=PYR:PYRUVIC+ACID'>PYR</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=5tvm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5tvm OCA], [https://pdbe.org/5tvm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5tvm RCSB], [https://www.ebi.ac.uk/pdbsum/5tvm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5tvm ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q587A7_TRYB2 Q587A7_TRYB2] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Catalytically inactive enzyme paralogs occur in many genomes. Some regulate their active counterparts but the structural principles of this regulation remain largely unknown. We report X-ray structures of Trypanosoma brucei S-adenosylmethionine decarboxylase alone and in functional complex with its catalytically dead paralogous partner, prozyme. We show monomeric TbAdoMetDC is inactive because of autoinhibition by its N-terminal sequence. Heterodimerization with prozyme displaces this sequence from the active site through a complex mechanism involving a cis-to-trans proline isomerization, reorganization of a beta-sheet, and insertion of the N-terminal alpha-helix into the heterodimer interface, leading to enzyme activation. We propose that the evolution of this intricate regulatory mechanism was facilitated by the acquisition of the dimerization domain, a single step that can in principle account for the divergence of regulatory schemes in the AdoMetDC enzyme family. These studies elucidate an allosteric mechanism in an enzyme and a plausible scheme by which such complex cooperativity evolved.

Relief of autoinhibition by conformational switch explains enzyme activation by a catalytically dead paralog.,Volkov OA, Kinch L, Ariagno C, Deng X, Zhong S, Grishin N, Tomchick DR, Chen Z, Phillips MA Elife. 2016 Dec 15;5. pii: e20198. doi: 10.7554/eLife.20198. PMID:27977001<ref>PMID:27977001</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5tvm" style="background-color:#fffaf0;"></div>

==See Also==
*[[SAM decarboxylase|SAM decarboxylase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Trypanosoma brucei brucei TREU927]]
[[Category: Chen Z]]
[[Category: Phillips MA]]
[[Category: Tomchick DR]]
[[Category: Volkov OA]]