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2dpr
From Proteopedia
(New page: 200px<br /><applet load="2dpr" size="350" color="white" frame="true" align="right" spinBox="true" caption="2dpr, resolution 1.7Å" /> '''The crystal structure...) |
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==Overview== | ==Overview== | ||
| - | Short peptides that have the ability to form stable alpha-helices in | + | Short peptides that have the ability to form stable alpha-helices in solution are rare, and a number of strategies have been used to produce them, including the use of metal chelation to stabilize folding of the backbone. However, no example exists of a structurally well-defined helix stabilized exclusively through metal ion chelation. Conantokins (con)-G and -T are short peptides that are potent antagonists of N-methyl-D-aspartate receptor channels. While con-G exhibits no helicity alone, it undergoes a structural transition to a helical conformation in the presence of a variety of multivalent cations, especially Mg2+ and Ca2+. This complexation also results in antiparallel dimerization of two peptide helices in the presence of Ca2+, but not Mg2+. A con-T variant, con-T[K7gamma], displays very similar behavior. We have solved the crystal structures of both Ca2+/con-G and Ca2+/con-T [K7gamma] at atomic resolution. These structures clearly show the nature of the metal-dependent dimerization and helix formation and surprisingly also show that the con-G dimer interface is completely different from the con-T[K7gamma] interface, even though the metal chelation is similar in the two peptides. This represents a new paradigm in helix stabilization completely independent of the hydrophobic effect, which we define as the "metallo-zipper." |
==About this Structure== | ==About this Structure== | ||
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The crystal structures of the calcium-bound con-G and con-T[K7gamma] dimeric peptides demonstrate a metal-dependent helix-forming motif., Cnudde SE, Prorok M, Dai Q, Castellino FJ, Geiger JH, J Am Chem Soc. 2007 Feb 14;129(6):1586-93. Epub 2007 Jan 23. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17243678 17243678] | The crystal structures of the calcium-bound con-G and con-T[K7gamma] dimeric peptides demonstrate a metal-dependent helix-forming motif., Cnudde SE, Prorok M, Dai Q, Castellino FJ, Geiger JH, J Am Chem Soc. 2007 Feb 14;129(6):1586-93. Epub 2007 Jan 23. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17243678 17243678] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Castellino, F | + | [[Category: Castellino, F J.]] |
| - | [[Category: Cnudde, S | + | [[Category: Cnudde, S E.]] |
[[Category: Dai, Q.]] | [[Category: Dai, Q.]] | ||
| - | [[Category: Geiger, J | + | [[Category: Geiger, J H.]] |
[[Category: Prorok, M.]] | [[Category: Prorok, M.]] | ||
[[Category: CA]] | [[Category: CA]] | ||
| Line 23: | Line 23: | ||
[[Category: nmdar antagonist]] | [[Category: nmdar antagonist]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:01:21 2008'' |
Revision as of 15:01, 21 February 2008
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The crystal structures of the calcium-bound con-G and con-T(K7Gla) dimeric peptides demonstrate a novel metal-dependent helix-forming motif
Overview
Short peptides that have the ability to form stable alpha-helices in solution are rare, and a number of strategies have been used to produce them, including the use of metal chelation to stabilize folding of the backbone. However, no example exists of a structurally well-defined helix stabilized exclusively through metal ion chelation. Conantokins (con)-G and -T are short peptides that are potent antagonists of N-methyl-D-aspartate receptor channels. While con-G exhibits no helicity alone, it undergoes a structural transition to a helical conformation in the presence of a variety of multivalent cations, especially Mg2+ and Ca2+. This complexation also results in antiparallel dimerization of two peptide helices in the presence of Ca2+, but not Mg2+. A con-T variant, con-T[K7gamma], displays very similar behavior. We have solved the crystal structures of both Ca2+/con-G and Ca2+/con-T [K7gamma] at atomic resolution. These structures clearly show the nature of the metal-dependent dimerization and helix formation and surprisingly also show that the con-G dimer interface is completely different from the con-T[K7gamma] interface, even though the metal chelation is similar in the two peptides. This represents a new paradigm in helix stabilization completely independent of the hydrophobic effect, which we define as the "metallo-zipper."
About this Structure
2DPR is a Protein complex structure of sequences from [1] with as ligand. Full crystallographic information is available from OCA.
Reference
The crystal structures of the calcium-bound con-G and con-T[K7gamma] dimeric peptides demonstrate a metal-dependent helix-forming motif., Cnudde SE, Prorok M, Dai Q, Castellino FJ, Geiger JH, J Am Chem Soc. 2007 Feb 14;129(6):1586-93. Epub 2007 Jan 23. PMID:17243678
Page seeded by OCA on Thu Feb 21 17:01:21 2008
