View source for 4cvq


==CRYSTAL STRUCTURE OF AN AMINOTRANSFERASE FROM ESCHERICHIA COLI AT 2. 11 ANGSTROEM RESOLUTION==
<StructureSection load='4cvq' size='340' side='right'caption='[[4cvq]], [[Resolution|resolution]] 2.11&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4cvq]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4CVQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4CVQ 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]] 2.11&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</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=4cvq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4cvq OCA], [https://pdbe.org/4cvq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4cvq RCSB], [https://www.ebi.ac.uk/pdbsum/4cvq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4cvq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ALAA_ECOLI ALAA_ECOLI] Involved in the biosynthesis of alanine. Catalyzes the transamination of pyruvate by glutamate, leading to the formation of L-alanine and 2-oxoglutarate. Is also able to catalyze the reverse reaction.<ref>PMID:20729367</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
In order to maintain proper cellular function, the metabolism of the bacterial microbiota presents several mechanisms oriented to keep a correctly balanced amino acid pool. Central components of these mechanisms are enzymes with alanine transaminase activity, pyridoxal 5'-phosphate-dependent enzymes that interconvert alanine and pyruvate, thereby allowing the precise control of alanine and glutamate concentrations, two of the most abundant amino acids in the cellular amino acid pool. Here we report the 2.11-A crystal structure of full-length AlaA from the model organism Escherichia coli, a major bacterial alanine aminotransferase, and compare its overall structure and active site composition with detailed atomic models of two other bacterial enzymes capable of catalyzing this reaction in vivo, AlaC and valine-pyruvate aminotransferase (AvtA). Apart from a narrow entry channel to the active site, a feature of this new crystal structure is the role of an active site loop that closes in upon binding of substrate-mimicking molecules, and which has only been previously reported in a plant enzyme. Comparison of the available structures indicates that beyond superficial differences, alanine aminotransferases of diverse phylogenetic origins share a universal reaction mechanism that depends on an array of highly conserved amino acid residues and is similarly regulated by various unrelated motifs. Despite this unifying mechanism and regulation, growth competition experiments demonstrate that AlaA, AlaC and AvtA are not freely exchangeable in vivo, suggesting that their functional repertoire is not completely redundant thus providing an explanation for their independent evolutionary conservation.

Structural Analysis and Mutant Growth Properties Reveal Distinctive Enzymatic and Cellular Roles for the Three Major L-Alanine Transaminases of Escherichia coli.,Pena-Soler E, Fernandez FJ, Lopez-Estepa M, Garces F, Richardson AJ, Quintana JF, Rudd KE, Coll M, Vega MC PLoS One. 2014 Jul 11;9(7):e102139. doi: 10.1371/journal.pone.0102139., eCollection 2014. PMID:25014014<ref>PMID:25014014</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4cvq" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Coll M]]
[[Category: Fernandez FJ]]
[[Category: Garces F]]
[[Category: Lopez-Estepa M]]
[[Category: Penya-Soler E]]
[[Category: Richardson AJ]]
[[Category: Rudd KE]]
[[Category: Vega MC]]