1amr

<StructureSection load='1amr' size='340' side='right' caption='[[1amr]], [[Resolution|resolution]] 2.10&Aring;' scene=''>

<table><tr><td colspan='2'>[[1amr]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AMR OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1AMR FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MAE:MALEIC+ACID'>MAE</scene>, <scene name='pdbligand=PMP:4-DEOXY-4-AMINOPYRIDOXAL-5-PHOSPHATE'>PMP</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Aspartate_transaminase Aspartate transaminase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.6.1.1 2.6.1.1] </span></td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1amr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1amr OCA], [http://pdbe.org/1amr PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1amr RCSB], [http://www.ebi.ac.uk/pdbsum/1amr PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1amr ProSAT]</span></td></tr>

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/am/1amr_consurf.spt"</scriptWhenChecked>

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== Publication Abstract from PubMed ==

The three-dimensional structures of pyridoxamine 5'-phosphate-type aspartate aminotransferase from Escherichia coli and its complexes with maleate and glutarate have been determined by X-ray crystallography at 2.2, 2.1, and 2.7 A resolution, respectively. The enzyme is a dimeric form comprising two identical subunits, each of which is divided into one large and one small domain. The complex with maleate showed that substrate (or inhibitor) binding induced a large conformational change from the "open" to the "closed" form, resulting in closure of the active site by the small domain movement, as was observed in the pyridoxal 5'-phosphate-type enzyme. In the open form, three hydrophobic residues (hydrophobic plug) at the entrance of the active site are exposed to solvent. Maleate binding make the active site more hydrophobic by charge compensation and release of water molecules, facilitating the movement of the hydrophobic plug into the active site pocket to induce a large conformational change in the enzyme. Maleate is fixed rigidly in the active site pocket by extensive salt bridges and a hydrogen bonding network, guaranteeing the stereo-specificity of the catalysis and giving a Michaelis complex model. Contrary to our expectation, the glutarate complex was in the open form, suggesting that the equilibrium between the open and closed forms lies far toward the open form in solution. The water molecules located in the active site pocket were almost completely conserved between Escherichia coli and chicken mitochondrial aspartate aminotransferase with the same type of cofactor and the same conformation.

 

== References ==

[[Category: Bacillus coli migula 1895]]

[[Category: Aspartate transaminase]]

[[Category: Hayashi, H]]

[[Category: Hirotsu, K]]

[[Category: Kagamiyama, H]]

[[Category: Miyahara, I]]