This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1x7w
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:1x7w.jpg|left|200px]] | + | [[Image:1x7w.jpg|left|200px]] |
| - | + | ||
| - | '''Crystal structure of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase''' | + | {{Structure |
| + | |PDB= 1x7w |SIZE=350|CAPTION= <scene name='initialview01'>1x7w</scene>, resolution 1.73Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=TDP:THIAMIN+DIPHOSPHATE'>TDP</scene> and <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/3-methyl-2-oxobutanoate_dehydrogenase_(2-methylpropanoyl-transferring) 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.2.4.4 1.2.4.4] | ||
| + | |GENE= BCKDHA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]), BCKDHB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | ||
| + | }} | ||
| + | |||
| + | '''Crystal structure of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 10: | Line 19: | ||
==About this Structure== | ==About this Structure== | ||
| - | 1X7W is a [ | + | 1X7W is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1X7W OCA]. |
==Reference== | ==Reference== | ||
| - | 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:[http:// | + | 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:[http://www.ncbi.nlm.nih.gov/pubmed/15576032 15576032] |
[[Category: 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)]] | [[Category: 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)]] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
| Line 39: | Line 48: | ||
[[Category: thiamin diphosphate]] | [[Category: thiamin diphosphate]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 15:06:13 2008'' |
Revision as of 13:06, 20 March 2008
| |||||||
| , resolution 1.73Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , , and | ||||||
| Gene: | BCKDHA (Homo sapiens), BCKDHB (Homo sapiens) | ||||||
| Activity: | 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring), with EC number 1.2.4.4 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of the human mitochondrial branched-chain alpha-ketoacid dehydrogenase
Contents |
Overview
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.
Disease
Known diseases associated with this structure: Maple syrup urine disease, type Ia OMIM:[608348], Maple syrup urine disease, type Ib OMIM:[248611]
About this Structure
1X7W is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
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
Page seeded by OCA on Thu Mar 20 15:06:13 2008
Categories: 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring) | Homo sapiens | Protein complex | Chuang, D T. | Chuang, J L. | Kato, M. | Li, J. | Machius, M. | Tomchick, D R. | Wynn, R M. | CL | GOL | K | MN | TDP | Acylation | Branched-chain | Flavoprotein | Ketoacid dehydrogenase | Multi-enzyme complex | Oxidative decarboxylation maple syrup urine disease | Oxidoreductase | Phosphorylation | Thiamin diphosphate
