2ic1
From Proteopedia
(New page: 200px<br /> <applet load="2ic1" size="450" color="white" frame="true" align="right" spinBox="true" caption="2ic1, resolution 2.7Å" /> '''Crystal Structure of...) |
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| - | [[Image:2ic1.gif|left|200px]]<br /> | + | [[Image:2ic1.gif|left|200px]]<br /><applet load="2ic1" size="350" color="white" frame="true" align="right" spinBox="true" |
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caption="2ic1, resolution 2.7Å" /> | caption="2ic1, resolution 2.7Å" /> | ||
'''Crystal Structure of Human Cysteine Dioxygenase in Complex with Substrate Cysteine'''<br /> | '''Crystal Structure of Human Cysteine Dioxygenase in Complex with Substrate Cysteine'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Cysteine dioxygenase is a non-heme mononuclear iron metalloenzyme that | + | Cysteine dioxygenase is a non-heme mononuclear iron metalloenzyme that catalyzes the oxidation of cysteine to cysteine sulfinic acid with addition of molecular dioxygen. This irreversible oxidative catabolism of cysteine initiates several important metabolic pathways related to diverse sulfurate compounds. Cysteine dioxygenase is therefore very important for maintaining the proper hepatic concentration of intracellular free cysteine. Mechanisms for mouse and rat cysteine dioxygenases have recently been reported based on their crystal structures in the absence of substrates, although there is still a lack of direct evidence. Here we report the first crystal structure of human cysteine dioxygenase in complex with its substrate L-cysteine to 2.7A, together with enzymatic activity and metal content assays of several single point mutants. Our results provide an insight into a new mechanism of cysteine thiol dioxygenation catalyzed by cysteine dioxygenase, which is tightly associated with a thioether-bonded tyrosine-cysteine cofactor involving Tyr-157 and Cys-93. This cross-linked protein-derived cofactor plays several key roles different from those in galactose oxidase. This report provides a new potential target for therapy of diseases related to human cysteine dioxygenase, including neurodegenerative and autoimmune diseases. |
==About this Structure== | ==About this Structure== | ||
| - | 2IC1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with FE2 and CYS as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Cysteine_dioxygenase Cysteine dioxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.20 1.13.11.20] Full crystallographic information is available from [http:// | + | 2IC1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=FE2:'>FE2</scene> and <scene name='pdbligand=CYS:'>CYS</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Cysteine_dioxygenase Cysteine dioxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.20 1.13.11.20] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2IC1 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: enzyme-substrate complex]] | [[Category: enzyme-substrate complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:51:02 2008'' |
Revision as of 15:51, 21 February 2008
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Crystal Structure of Human Cysteine Dioxygenase in Complex with Substrate Cysteine
Overview
Cysteine dioxygenase is a non-heme mononuclear iron metalloenzyme that catalyzes the oxidation of cysteine to cysteine sulfinic acid with addition of molecular dioxygen. This irreversible oxidative catabolism of cysteine initiates several important metabolic pathways related to diverse sulfurate compounds. Cysteine dioxygenase is therefore very important for maintaining the proper hepatic concentration of intracellular free cysteine. Mechanisms for mouse and rat cysteine dioxygenases have recently been reported based on their crystal structures in the absence of substrates, although there is still a lack of direct evidence. Here we report the first crystal structure of human cysteine dioxygenase in complex with its substrate L-cysteine to 2.7A, together with enzymatic activity and metal content assays of several single point mutants. Our results provide an insight into a new mechanism of cysteine thiol dioxygenation catalyzed by cysteine dioxygenase, which is tightly associated with a thioether-bonded tyrosine-cysteine cofactor involving Tyr-157 and Cys-93. This cross-linked protein-derived cofactor plays several key roles different from those in galactose oxidase. This report provides a new potential target for therapy of diseases related to human cysteine dioxygenase, including neurodegenerative and autoimmune diseases.
About this Structure
2IC1 is a Single protein structure of sequence from Homo sapiens with and as ligands. Active as Cysteine dioxygenase, with EC number 1.13.11.20 Full crystallographic information is available from OCA.
Reference
An insight into the mechanism of human cysteine dioxygenase. Key roles of the thioether-bonded tyrosine-cysteine cofactor., Ye S, Wu X, Wei L, Tang D, Sun P, Bartlam M, Rao Z, J Biol Chem. 2007 Feb 2;282(5):3391-402. Epub 2006 Nov 29. PMID:17135237
Page seeded by OCA on Thu Feb 21 17:51:02 2008
Categories: Cysteine dioxygenase | Homo sapiens | Single protein | Rao, Z. | Sun, P. | Tang, D. | Wei, L. | Wu, X. | Ye, S. | CYS | FE2 | Cupin | Enzyme-substrate complex
