|
|
| (2 intermediate revisions not shown.) |
| Line 1: |
Line 1: |
| | | | |
| | ==Crystal structure of reduced human cytosolic branched-chain aminotransferase complexed with gabapentin== | | ==Crystal structure of reduced human cytosolic branched-chain aminotransferase complexed with gabapentin== |
| - | <StructureSection load='2coj' size='340' side='right' caption='[[2coj]], [[Resolution|resolution]] 2.40Å' scene=''> | + | <StructureSection load='2coj' size='340' side='right'caption='[[2coj]], [[Resolution|resolution]] 2.40Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[2coj]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2COJ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2COJ FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[2coj]] 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=2COJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2COJ FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GBN:[1-(AMINOMETHYL)CYCLOHEXYL]ACETIC+ACID'>GBN</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.4Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2cog|2cog]], [[2coi|2coi]]</td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GBN:[1-(AMINOMETHYL)CYCLOHEXYL]ACETIC+ACID'>GBN</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene></td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Branched-chain-amino-acid_transaminase Branched-chain-amino-acid transaminase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.6.1.42 2.6.1.42] </span></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=2coj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2coj OCA], [https://pdbe.org/2coj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2coj RCSB], [https://www.ebi.ac.uk/pdbsum/2coj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2coj ProSAT]</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=2coj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2coj OCA], [http://pdbe.org/2coj PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2coj RCSB], [http://www.ebi.ac.uk/pdbsum/2coj PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2coj ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/BCAT1_HUMAN BCAT1_HUMAN]] Catalyzes the first reaction in the catabolism of the essential branched chain amino acids leucine, isoleucine, and valine. | + | [https://www.uniprot.org/uniprot/BCAT1_HUMAN BCAT1_HUMAN] Catalyzes the first reaction in the catabolism of the essential branched chain amino acids leucine, isoleucine, and valine. |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
| Line 34: |
Line 33: |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Branched-chain-amino-acid transaminase]] | + | [[Category: Homo sapiens]] |
| - | [[Category: Human]] | + | [[Category: Large Structures]] |
| - | [[Category: Goto, M]] | + | [[Category: Goto M]] |
| - | [[Category: Plp-dependent enzyme]]
| + | |
| - | [[Category: Transferase]]
| + | |
| Structural highlights
Function
BCAT1_HUMAN Catalyzes the first reaction in the catabolism of the essential branched chain amino acids leucine, isoleucine, and valine.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
This study presents the first three-dimensional structures of human cytosolic branched-chain aminotransferase (hBCATc) isozyme complexed with the neuroactive drug gabapentin, the hBCATc Michaelis complex with the substrate analog, 4-methylvalerate, and the mitochondrial isozyme (hBCATm) complexed with gabapentin. The branched-chain aminotransferases (BCAT) reversibly catalyze transamination of the essential branched-chain amino acids (leucine, isoleucine, valine) to alpha-ketoglutarate to form the respective branched-chain alpha-keto acids and glutamate. The cytosolic isozyme is the predominant BCAT found in the nervous system, and only hBCATc is inhibited by gabapentin. Pre-steady state kinetics show that 1.3 mm gabapentin can completely inhibit the binding of leucine to reduced hBCATc, whereas 65.4 mm gabapentin is required to inhibit leucine binding to hBCATm. Structural analysis shows that the bulky gabapentin is enclosed in the active-site cavity by the shift of a flexible loop that enlarges the active-site cavity. The specificity of gabapentin for the cytosolic isozyme is ascribed at least in part to the location of the interdomain loop and the relative orientation between the small and large domain which is different from these relationships in the mitochondrial isozyme. Both isozymes contain a CXXC center and form a disulfide bond under oxidizing conditions. The structure of reduced hBCATc was obtained by soaking the oxidized hBCATc crystals with dithiothreitol. The close similarity in active-site structures between cytosolic enzyme complexes in the oxidized and reduced states is consistent with the small effect of oxidation on pre-steady state kinetics of the hBCATc first half-reaction. However, these kinetic data do not explain the inactivation of hBCATm by oxidation of the CXXC center. The structural data suggest that there is a larger effect of oxidation on the interdomain loop and residues surrounding the CXXC center in hBCATm than in hBCATc.
Structural determinants for branched-chain aminotransferase isozyme-specific inhibition by the anticonvulsant drug gabapentin.,Goto M, Miyahara I, Hirotsu K, Conway M, Yennawar N, Islam MM, Hutson SM J Biol Chem. 2005 Nov 4;280(44):37246-56. Epub 2005 Sep 1. PMID:16141215[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Goto M, Miyahara I, Hirotsu K, Conway M, Yennawar N, Islam MM, Hutson SM. Structural determinants for branched-chain aminotransferase isozyme-specific inhibition by the anticonvulsant drug gabapentin. J Biol Chem. 2005 Nov 4;280(44):37246-56. Epub 2005 Sep 1. PMID:16141215 doi:10.1074/jbc.M506486200
|
