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2nnx
From Proteopedia
(New page: 200px<br /> <applet load="2nnx" size="450" color="white" frame="true" align="right" spinBox="true" caption="2nnx, resolution 2.30Å" /> '''Crystal Structure o...) |
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| - | [[Image:2nnx.gif|left|200px]]<br /> | + | [[Image:2nnx.gif|left|200px]]<br /><applet load="2nnx" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="2nnx" size=" | + | |
caption="2nnx, resolution 2.30Å" /> | caption="2nnx, resolution 2.30Å" /> | ||
'''Crystal Structure of the H46R, H48Q double mutant of human [Cu-Zn] Superoxide Dismutase'''<br /> | '''Crystal Structure of the H46R, H48Q double mutant of human [Cu-Zn] Superoxide Dismutase'''<br /> | ||
==Overview== | ==Overview== | ||
| - | A subset of superoxide dismutase 1 (Cu/Zn-SOD1) mutants that cause | + | A subset of superoxide dismutase 1 (Cu/Zn-SOD1) mutants that cause familial amyotrophic lateral sclerosis (FALS) have heightened reactivity with (-)ONOO and H(2)O(2) in vitro. This reactivity requires a copper ion bound in the active site and is a suggested mechanism of motor neuron injury. However, we have found that transgenic mice that express SOD1-H46R/H48Q, which combines natural FALS mutations at ligands for copper and which is inactive, develop motor neuron disease. Using a direct radioactive copper incorporation assay in transfected cells and the established tools of single crystal x-ray diffraction, we now demonstrate that this variant does not stably bind copper. We find that single mutations at copper ligands, including H46R, H48Q, and a quadruple mutant H46R/H48Q/H63G/H120G, also diminish the binding of radioactive copper. Further, using native polyacrylamide gel electrophoresis and a yeast two-hybrid assay, the binding of copper was found to be related to the formation of the stable dimeric enzyme. Collectively, our data demonstrate a relationship between copper and assembly of SOD1 into stable dimers and also define disease-causing SOD1 mutants that are unlikely to robustly produce toxic radicals via copper-mediated chemistry. |
==Disease== | ==Disease== | ||
| Line 11: | Line 10: | ||
==About this Structure== | ==About this Structure== | ||
| - | 2NNX 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 ZN, SO4 and ACE as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Superoxide_dismutase Superoxide dismutase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.15.1.1 1.15.1.1] Full crystallographic information is available from [http:// | + | 2NNX 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=ZN:'>ZN</scene>, <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=ACE:'>ACE</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Superoxide_dismutase Superoxide dismutase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.15.1.1 1.15.1.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2NNX OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Superoxide dismutase]] | [[Category: Superoxide dismutase]] | ||
| - | [[Category: Hart, P | + | [[Category: Hart, P J.]] |
| - | [[Category: Schuermann, J | + | [[Category: Schuermann, J P.]] |
[[Category: ACE]] | [[Category: ACE]] | ||
[[Category: SO4]] | [[Category: SO4]] | ||
| Line 25: | Line 24: | ||
[[Category: oxidoreductase; human; cu-zn superoxide dismutase; superoxide acceptor; familial amyotrophic lateral sclerosis mutant]] | [[Category: oxidoreductase; human; cu-zn superoxide dismutase; superoxide acceptor; familial amyotrophic lateral sclerosis mutant]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:08:58 2008'' |
Revision as of 16:09, 21 February 2008
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Crystal Structure of the H46R, H48Q double mutant of human [Cu-Zn] Superoxide Dismutase
Contents |
Overview
A subset of superoxide dismutase 1 (Cu/Zn-SOD1) mutants that cause familial amyotrophic lateral sclerosis (FALS) have heightened reactivity with (-)ONOO and H(2)O(2) in vitro. This reactivity requires a copper ion bound in the active site and is a suggested mechanism of motor neuron injury. However, we have found that transgenic mice that express SOD1-H46R/H48Q, which combines natural FALS mutations at ligands for copper and which is inactive, develop motor neuron disease. Using a direct radioactive copper incorporation assay in transfected cells and the established tools of single crystal x-ray diffraction, we now demonstrate that this variant does not stably bind copper. We find that single mutations at copper ligands, including H46R, H48Q, and a quadruple mutant H46R/H48Q/H63G/H120G, also diminish the binding of radioactive copper. Further, using native polyacrylamide gel electrophoresis and a yeast two-hybrid assay, the binding of copper was found to be related to the formation of the stable dimeric enzyme. Collectively, our data demonstrate a relationship between copper and assembly of SOD1 into stable dimers and also define disease-causing SOD1 mutants that are unlikely to robustly produce toxic radicals via copper-mediated chemistry.
Disease
Known disease associated with this structure: Amyotrophic lateral sclerosis, due to SOD1 deficiency OMIM:[147450]
About this Structure
2NNX is a Single protein structure of sequence from Homo sapiens with , and as ligands. Active as Superoxide dismutase, with EC number 1.15.1.1 Full crystallographic information is available from OCA.
Reference
Disease-associated mutations at copper ligand histidine residues of superoxide dismutase 1 diminish the binding of copper and compromise dimer stability., Wang J, Caruano-Yzermans A, Rodriguez A, Scheurmann JP, Slunt HH, Cao X, Gitlin J, Hart PJ, Borchelt DR, J Biol Chem. 2007 Jan 5;282(1):345-52. Epub 2006 Nov 8. PMID:17092942
Page seeded by OCA on Thu Feb 21 18:08:58 2008
