1not
From Proteopedia
(New page: 200px<br /><applet load="1not" size="450" color="white" frame="true" align="right" spinBox="true" caption="1not, resolution 1.2Å" /> '''THE 1.2 ANGSTROM STRU...) |
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| - | [[Image:1not.gif|left|200px]]<br /><applet load="1not" size=" | + | [[Image:1not.gif|left|200px]]<br /><applet load="1not" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1not, resolution 1.2Å" /> | caption="1not, resolution 1.2Å" /> | ||
'''THE 1.2 ANGSTROM STRUCTURE OF G1 ALPHA CONOTOXIN'''<br /> | '''THE 1.2 ANGSTROM STRUCTURE OF G1 ALPHA CONOTOXIN'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Predatory marine snails of the genus Conus paralyze their fish prey by | + | Predatory marine snails of the genus Conus paralyze their fish prey by injecting a potent toxin. The alpha-conotoxin GI is a 13-residue peptide isolated from venom of Conus geographus. It functions by blocking the postsynaptic nicotinic acetylcholine receptor. After crystallization in deionized water, the three-dimensional structure of the GI neurotoxin was determined to 1.2 A resolution by X-ray crystallography. This structure, which can be described as a triangular slab, shows overall similarities to those derived by NMR, CD, and predictive methods. The principal framework of the molecule is provided by two disulfide bonds, one linking Cys 2 and Cys 7 and the other Cys 3 and Cys 13. Opposite ends of the sequence are drawn together even further by hydrogen bonds between Glu 1 and Cys 13 and between Cys 2 and Ser 12. Since the C-terminus is amidated, only one negative charge is present (carboxylate of Glu 1), and this is not implicated in receptor binding. Two positively charged regions (the alpha-amino group of Glu 1 and the guanido group of Arg 9) are situated 15 A apart at the corners of the triangular face of the molecule. phi, psi angles characteristic of a 3(10) helix were observed for residues 5-7. For residues 8-11, these angles were consistent with either a type I beta-turn or a distorted 3(10) helix. |
==About this Structure== | ==About this Structure== | ||
| - | 1NOT is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Conus_geographus Conus geographus] with NH2 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1NOT is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Conus_geographus Conus geographus] with <scene name='pdbligand=NH2:'>NH2</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NOT OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Conus geographus]] | [[Category: Conus geographus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Edmundson, A | + | [[Category: Edmundson, A B.]] |
| - | [[Category: Gray, W | + | [[Category: Gray, W R.]] |
| - | [[Category: Guddat, L | + | [[Category: Guddat, L W.]] |
| - | [[Category: Martin, J | + | [[Category: Martin, J L.]] |
[[Category: Shan, L.]] | [[Category: Shan, L.]] | ||
[[Category: NH2]] | [[Category: NH2]] | ||
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[[Category: venom]] | [[Category: venom]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:08:24 2008'' |
Revision as of 12:08, 21 February 2008
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THE 1.2 ANGSTROM STRUCTURE OF G1 ALPHA CONOTOXIN
Overview
Predatory marine snails of the genus Conus paralyze their fish prey by injecting a potent toxin. The alpha-conotoxin GI is a 13-residue peptide isolated from venom of Conus geographus. It functions by blocking the postsynaptic nicotinic acetylcholine receptor. After crystallization in deionized water, the three-dimensional structure of the GI neurotoxin was determined to 1.2 A resolution by X-ray crystallography. This structure, which can be described as a triangular slab, shows overall similarities to those derived by NMR, CD, and predictive methods. The principal framework of the molecule is provided by two disulfide bonds, one linking Cys 2 and Cys 7 and the other Cys 3 and Cys 13. Opposite ends of the sequence are drawn together even further by hydrogen bonds between Glu 1 and Cys 13 and between Cys 2 and Ser 12. Since the C-terminus is amidated, only one negative charge is present (carboxylate of Glu 1), and this is not implicated in receptor binding. Two positively charged regions (the alpha-amino group of Glu 1 and the guanido group of Arg 9) are situated 15 A apart at the corners of the triangular face of the molecule. phi, psi angles characteristic of a 3(10) helix were observed for residues 5-7. For residues 8-11, these angles were consistent with either a type I beta-turn or a distorted 3(10) helix.
About this Structure
1NOT is a Single protein structure of sequence from Conus geographus with as ligand. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of the alpha-conotoxin GI at 1.2 A resolution., Guddat LW, Martin JA, Shan L, Edmundson AB, Gray WR, Biochemistry. 1996 Sep 3;35(35):11329-35. PMID:8784187
Page seeded by OCA on Thu Feb 21 14:08:24 2008
