1dub: Difference between revisions
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==Overview== | ==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, ... | 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== | ||
1DUB is a | 1DUB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with CAA as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Enoyl-CoA_hydratase Enoyl-CoA hydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.17 4.2.1.17] Structure known Active Sites: CR1 and CR2. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1DUB OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: lyase]] | [[Category: lyase]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:57:06 2007'' | ||
