1dub: Difference between revisions
No edit summary |
No edit summary |
||
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
The crystal structure of rat liver mitochondrial enoyl-coenzyme A (CoA) | The crystal structure of rat liver mitochondrial enoyl-coenzyme A (CoA) hydratase complexed with the potent inhibitor acetoacetyl-CoA has been refined at 2.5 angstroms resolution. This enzyme catalyses the reversible addition of water to alpha,beta-unsaturated enoyl-CoA thioesters, with nearly diffusion-controlled reaction rates for the best substrates. Enoyl-CoA hydratase is a hexamer of six identical subunits of 161 kDa molecular mass for the complex. The hexamer is a dimer of trimers. The monomer is folded into a right-handed spiral of four turns, followed by two small domains which are involved in trimerization. Each turn of the spiral consists of two beta-strands and an alpha-helix. The mechanism for the hydratase/dehydratase reaction follows a syn-stereochemistry, a preference that is opposite to the nonenzymatic reaction. The active-site architecture agrees with this stereochemistry. It confirms the importance of Glu164 as the catalytic acid for providing the alpha-proton during the hydratase reaction. It also shows the importance of Glu144 as the catalytic base for the activation of a water molecule in the hydratase reaction. The comparison of an unliganded and a liganded active site within the same crystal form shows a water molecule in the unliganded subunit. This water molecule is bound between the two catalytic glutamates and could serve as the activated water during catalysis. | ||
==About this Structure== | ==About this Structure== | ||
| Line 14: | Line 14: | ||
[[Category: Rattus norvegicus]] | [[Category: Rattus norvegicus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Engel, C | [[Category: Engel, C K.]] | ||
[[Category: Wierenga, R | [[Category: Wierenga, R K.]] | ||
[[Category: CAA]] | [[Category: CAA]] | ||
[[Category: beta-oxidation]] | [[Category: beta-oxidation]] | ||
| Line 24: | Line 24: | ||
[[Category: lyase]] | [[Category: lyase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:20:30 2008'' | ||
Revision as of 10:20, 21 February 2008
|
2-ENOYL-COA HYDRATASE, DATA COLLECTED AT 100 K, PH 6.5
Overview
The crystal structure of rat liver mitochondrial enoyl-coenzyme A (CoA) hydratase complexed with the potent inhibitor acetoacetyl-CoA has been refined at 2.5 angstroms resolution. This enzyme catalyses the reversible addition of water to alpha,beta-unsaturated enoyl-CoA thioesters, with nearly diffusion-controlled reaction rates for the best substrates. Enoyl-CoA hydratase is a hexamer of six identical subunits of 161 kDa molecular mass for the complex. The hexamer is a dimer of trimers. The monomer is folded into a right-handed spiral of four turns, followed by two small domains which are involved in trimerization. Each turn of the spiral consists of two beta-strands and an alpha-helix. The mechanism for the hydratase/dehydratase reaction follows a syn-stereochemistry, a preference that is opposite to the nonenzymatic reaction. The active-site architecture agrees with this stereochemistry. It confirms the importance of Glu164 as the catalytic acid for providing the alpha-proton during the hydratase reaction. It also shows the importance of Glu144 as the catalytic base for the activation of a water molecule in the hydratase reaction. The comparison of an unliganded and a liganded active site within the same crystal form shows a water molecule in the unliganded subunit. This water molecule is bound between the two catalytic glutamates and could serve as the activated water during catalysis.
About this Structure
1DUB is a Single protein structure of sequence from Rattus norvegicus with CAA as ligand. Active as Enoyl-CoA hydratase, with EC number 4.2.1.17 Known structural/functional Sites: CR1 and CR2. Full crystallographic information is available from OCA.
Reference
Crystal structure of enoyl-coenzyme A (CoA) hydratase at 2.5 angstroms resolution: a spiral fold defines the CoA-binding pocket., Engel CK, Mathieu M, Zeelen JP, Hiltunen JK, Wierenga RK, EMBO J. 1996 Oct 1;15(19):5135-45. PMID:8895557
Page seeded by OCA on Thu Feb 21 12:20:30 2008
