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1u5b
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| - | [[Image:1u5b.jpg|left|200px]]<br /><applet load="1u5b" size="350" color="white" frame="true" align="right" spinBox="true" | ||
| - | caption="1u5b, resolution 1.83Å" /> | ||
| - | '''Crystal structure of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase'''<br /> | ||
| - | == | + | ==Crystal structure of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase== |
| + | <StructureSection load='1u5b' size='340' side='right'caption='[[1u5b]], [[Resolution|resolution]] 1.83Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[1u5b]] 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=1U5B OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1U5B 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]] 1.83Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=TPP:THIAMINE+DIPHOSPHATE'>TPP</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=1u5b FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1u5b OCA], [https://pdbe.org/1u5b PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1u5b RCSB], [https://www.ebi.ac.uk/pdbsum/1u5b PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1u5b ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Disease == | ||
| + | [https://www.uniprot.org/uniprot/ODBA_HUMAN ODBA_HUMAN] Defects in BCKDHA are a cause of maple syrup urine disease type IA (MSUD1A) [MIM:[https://omim.org/entry/248600 248600]. MSUD is an autosomal recessive disorder characterized by mental and physical retardation, feeding problems, and a maple syrup odor to the urine.<ref>PMID:2060625</ref> <ref>PMID:8037208</ref> <ref>PMID:2703538</ref> <ref>PMID:2241958</ref> <ref>PMID:1867199</ref> <ref>PMID:1885764</ref> <ref>PMID:8161368</ref> <ref>PMID:7883996</ref> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/ODBA_HUMAN ODBA_HUMAN] The branched-chain alpha-keto dehydrogenase complex catalyzes the overall conversion of alpha-keto acids to acyl-CoA and CO(2). It contains multiple copies of three enzymatic components: branched-chain alpha-keto acid decarboxylase (E1), lipoamide acyltransferase (E2) and lipoamide dehydrogenase (E3). | ||
| + | == 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/u5/1u5b_consurf.spt"</scriptWhenChecked> | ||
| + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.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=1u5b ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
The human mitochondrial branched-chain alpha-ketoacid dehydrogenase complex (BCKDC) is a 4 MDa macromolecular machine comprising three catalytic components (E1b, E2b, and E3), a kinase, and a phosphatase. The BCKDC overall activity is tightly regulated by phosphorylation in response to hormonal and dietary stimuli. We report that phosphorylation of Ser292-alpha in the E1b active site channel results in an order-to-disorder transition of the conserved phosphorylation loop carrying the phosphoryl serine. The conformational change is triggered by steric clashes of the phosphoryl group with invariant His291-alpha that serves as an indispensable anchor for the phosphorylation loop through bound thiamin diphosphate. Phosphorylation of Ser292-alpha does not severely impede the E1b-dependent decarboxylation of alpha-ketoacids. However, the disordered loop conformation prevents phosphorylated E1b from binding the E2b lipoyl-bearing domain, which effectively shuts off the E1b-catalyzed reductive acylation reaction and therefore completely inactivates BCKDC. This mechanism provides a paradigm for regulation of mitochondrial alpha-ketoacid dehydrogenase complexes by phosphorylation. | The human mitochondrial branched-chain alpha-ketoacid dehydrogenase complex (BCKDC) is a 4 MDa macromolecular machine comprising three catalytic components (E1b, E2b, and E3), a kinase, and a phosphatase. The BCKDC overall activity is tightly regulated by phosphorylation in response to hormonal and dietary stimuli. We report that phosphorylation of Ser292-alpha in the E1b active site channel results in an order-to-disorder transition of the conserved phosphorylation loop carrying the phosphoryl serine. The conformational change is triggered by steric clashes of the phosphoryl group with invariant His291-alpha that serves as an indispensable anchor for the phosphorylation loop through bound thiamin diphosphate. Phosphorylation of Ser292-alpha does not severely impede the E1b-dependent decarboxylation of alpha-ketoacids. However, the disordered loop conformation prevents phosphorylated E1b from binding the E2b lipoyl-bearing domain, which effectively shuts off the E1b-catalyzed reductive acylation reaction and therefore completely inactivates BCKDC. This mechanism provides a paradigm for regulation of mitochondrial alpha-ketoacid dehydrogenase complexes by phosphorylation. | ||
| - | + | Molecular mechanism for regulation of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase complex by phosphorylation.,Wynn RM, Kato M, Machius M, Chuang JL, Li J, Tomchick DR, Chuang DT Structure. 2004 Dec;12(12):2185-96. PMID:15576032<ref>PMID:15576032</ref> | |
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 1u5b" style="background-color:#fffaf0;"></div> | |
| - | + | == References == | |
| - | + | <references/> | |
| - | + | __TOC__ | |
| + | </StructureSection> | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
| - | [[Category: | + | [[Category: Large Structures]] |
| - | [[Category: Chuang | + | [[Category: Chuang DT]] |
| - | [[Category: Chuang | + | [[Category: Chuang JL]] |
| - | [[Category: Kato | + | [[Category: Kato M]] |
| - | [[Category: Li | + | [[Category: Li J]] |
| - | [[Category: Machius | + | [[Category: Machius M]] |
| - | [[Category: Tomchick | + | [[Category: Tomchick DR]] |
| - | [[Category: Wynn | + | [[Category: Wynn RM]] |
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Current revision
Crystal structure of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase
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Categories: Homo sapiens | Large Structures | Chuang DT | Chuang JL | Kato M | Li J | Machius M | Tomchick DR | Wynn RM
