View source for 1ekv


==HUMAN BRANCHED CHAIN AMINO ACID AMINOTRANSFERASE (MITOCHONDRIAL): THREE DIMENSIONAL STRUCTURE OF ENZYME INACTIVATED BY TRIS BOUND TO THE PYRIDOXAL-5'-PHOSPHATE ON ONE END AND ACTIVE SITE LYS202 NZ ON THE OTHER.==
<StructureSection load='1ekv' size='340' side='right'caption='[[1ekv]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ekv]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EKV OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1EKV 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]] 2.25&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene>, <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</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=1ekv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ekv OCA], [https://pdbe.org/1ekv PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ekv RCSB], [https://www.ebi.ac.uk/pdbsum/1ekv PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ekv ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/BCAT2_HUMAN BCAT2_HUMAN] Catalyzes the first reaction in the catabolism of the essential branched chain amino acids leucine, isoleucine, and valine. May also function as a transporter of branched chain alpha-keto acids.
== 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/ek/1ekv_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=1ekv ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
X-ray crystal structures of three forms of human mitochondrial branched-chain aminotransferase (BCAT) were solved by molecular-replacement methods, using Escherichia coli BCAT as the search model. The enzyme is a homodimer and the polypeptide chain of each monomer has two domains. The small domain is composed of residues 1--175 and the large domain is composed of residues 176--365. The active site is close to the dimer interface. The 4'-aldehyde of the PLP cofactor is covalently linked to the epsilon-amino group of the active-site lysine, Lys202, via a Schiff-base linkage in two of the structures. In the third structure, the enzyme is irreversibly inactivated by Tris. The overall fold of the dimer in human mitochondrial BCAT is similar to the structure of two bacterial enzymes, E. coli BCAT and D-amino acid aminotransferase (D-AAT). The residues lining the putative substrate-binding pocket of human BCAT and D-AAT are completely rearranged to allow catalysis with substrates of opposite stereochemistry. In the case of human mitochondrial branched-chain aminotransferase, a hydrogen-bond interaction between the guanidinium group of Arg143 in the first monomer with the side-chain hydroxyl of Tyr70 in the second monomer is important in the formation of the substrate-binding pocket.

The structure of human mitochondrial branched-chain aminotransferase.,Yennawar N, Dunbar J, Conway M, Hutson S, Farber G Acta Crystallogr D Biol Crystallogr. 2001 Apr;57(Pt 4):506-15. PMID:11264579<ref>PMID:11264579</ref>

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

==See Also==
*[[Aminotransferase 3D structures|Aminotransferase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Conway M]]
[[Category: Dunbar JH]]
[[Category: Farber GK]]
[[Category: Hutson SM]]
[[Category: Yennawar NH]]