1gof
From Proteopedia
(New page: 200px<br /><applet load="1gof" size="450" color="white" frame="true" align="right" spinBox="true" caption="1gof, resolution 1.7Å" /> '''NOVEL THIOETHER BOND ...) |
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| - | [[Image:1gof.gif|left|200px]]<br /><applet load="1gof" size=" | + | [[Image:1gof.gif|left|200px]]<br /><applet load="1gof" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1gof, resolution 1.7Å" /> | caption="1gof, resolution 1.7Å" /> | ||
'''NOVEL THIOETHER BOND REVEALED BY A 1.7 ANGSTROMS CRYSTAL STRUCTURE OF GALACTOSE OXIDASE'''<br /> | '''NOVEL THIOETHER BOND REVEALED BY A 1.7 ANGSTROMS CRYSTAL STRUCTURE OF GALACTOSE OXIDASE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Galactose oxidase is an extracellular enzyme secreted by the fungus | + | Galactose oxidase is an extracellular enzyme secreted by the fungus Dactylium dendroides. It is monomeric, with a relative molecular mass of 68,000, catalyses the stereospecific oxidation of a broad range of primary alcohol substrates and possesses a unique mononuclear copper site essential for catalysing a two-electron transfer reaction during the oxidation of primary alcohols to corresponding aldehydes. Recent evidence arguing against a Cu(III)-Cu(I) couple implies the existence of a second redox-active site proposed to involve pyrroloquinoline quinone or a tyrosine radical. We now report the crystal structure of galactose oxidase at 1.7 A resolution. This reveals a unique structural feature at the copper site with a novel thioether bond linking Cys 228 and Tyr 272 in a stacking interaction with Trp 290. We propose that these molecular components stabilize the protein free-radical species essential for catalysis and thus provide a 'built-in' secondary cofactor. This feature may represent a new mechanism for mediating electron transfer in metalloenzymes in the absence of exogenous cofactors. |
==About this Structure== | ==About this Structure== | ||
| - | 1GOF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Hypomyces_rosellus Hypomyces rosellus] with CU, NA and ACY as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Galactose_oxidase Galactose oxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.3.9 1.1.3.9] Full crystallographic information is available from [http:// | + | 1GOF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Hypomyces_rosellus Hypomyces rosellus] with <scene name='pdbligand=CU:'>CU</scene>, <scene name='pdbligand=NA:'>NA</scene> and <scene name='pdbligand=ACY:'>ACY</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Galactose_oxidase Galactose oxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.3.9 1.1.3.9] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GOF OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Ito, N.]] | [[Category: Ito, N.]] | ||
| - | [[Category: Knowles, P | + | [[Category: Knowles, P F.]] |
| - | [[Category: Phillips, S | + | [[Category: Phillips, S E.V.]] |
[[Category: ACY]] | [[Category: ACY]] | ||
[[Category: CU]] | [[Category: CU]] | ||
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[[Category: oxidoreductase(oxygen(a))]] | [[Category: oxidoreductase(oxygen(a))]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:52:16 2008'' |
Revision as of 10:52, 21 February 2008
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NOVEL THIOETHER BOND REVEALED BY A 1.7 ANGSTROMS CRYSTAL STRUCTURE OF GALACTOSE OXIDASE
Overview
Galactose oxidase is an extracellular enzyme secreted by the fungus Dactylium dendroides. It is monomeric, with a relative molecular mass of 68,000, catalyses the stereospecific oxidation of a broad range of primary alcohol substrates and possesses a unique mononuclear copper site essential for catalysing a two-electron transfer reaction during the oxidation of primary alcohols to corresponding aldehydes. Recent evidence arguing against a Cu(III)-Cu(I) couple implies the existence of a second redox-active site proposed to involve pyrroloquinoline quinone or a tyrosine radical. We now report the crystal structure of galactose oxidase at 1.7 A resolution. This reveals a unique structural feature at the copper site with a novel thioether bond linking Cys 228 and Tyr 272 in a stacking interaction with Trp 290. We propose that these molecular components stabilize the protein free-radical species essential for catalysis and thus provide a 'built-in' secondary cofactor. This feature may represent a new mechanism for mediating electron transfer in metalloenzymes in the absence of exogenous cofactors.
About this Structure
1GOF is a Single protein structure of sequence from Hypomyces rosellus with , and as ligands. Active as Galactose oxidase, with EC number 1.1.3.9 Full crystallographic information is available from OCA.
Reference
Novel thioether bond revealed by a 1.7 A crystal structure of galactose oxidase., Ito N, Phillips SE, Stevens C, Ogel ZB, McPherson MJ, Keen JN, Yadav KD, Knowles PF, Nature. 1991 Mar 7;350(6313):87-90. PMID:2002850
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