1qs3
From Proteopedia
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|PDB= 1qs3 |SIZE=350|CAPTION= <scene name='initialview01'>1qs3</scene> | |PDB= 1qs3 |SIZE=350|CAPTION= <scene name='initialview01'>1qs3</scene> | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=NH2:AMINO GROUP'>NH2</scene> | + | |LIGAND= <scene name='pdbligand=NH2:AMINO+GROUP'>NH2</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1qs3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qs3 OCA], [http://www.ebi.ac.uk/pdbsum/1qs3 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1qs3 RCSB]</span> | ||
}} | }} | ||
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[[Category: Han, K H.]] | [[Category: Han, K H.]] | ||
[[Category: Mok, K H.]] | [[Category: Mok, K H.]] | ||
| - | [[Category: NH2]] | ||
[[Category: antitoxic analog]] | [[Category: antitoxic analog]] | ||
[[Category: conotoxin]] | [[Category: conotoxin]] | ||
[[Category: nicotinic acetylcholine receptor]] | [[Category: nicotinic acetylcholine receptor]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 23:18:12 2008'' |
Revision as of 20:18, 30 March 2008
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| Ligands: | |||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
NMR SOLUTION CONFORMATION OF AN ANTITOXIC ANALOG OF ALPHA-CONOTOXIN GI
Overview
The three-dimensional solution conformation of an 11-residue antitoxic analogue of alpha-conotoxin GI, des-Glu1-[Cys3Ala]-des-Cys13-conotoxin GI (CANPACGRHYS-NH(2), designated "GI-15" henceforth), has been determined using two-dimensional (1)H NMR spectroscopy. The disulfide loop region (1C-6C) and the C-terminal tail (8R-11S) are connected by a flexible hinge formed near 7G, and the pairwise backbone rmsds for the former and the latter are 0.58 and 0.65 A, respectively. Superpositioning GI-15 with the structure of alpha-conotoxin GI shows that the two share an essentially identical fold in the common first disulfide loop region (1C-6C). However, the absence of the second disulfide loop in GI-15 results in segmental motion of the C-terminal half, causing the key receptor subtype selectivity residue 8R (Arg9 in alpha-conotoxin GI) to lose its native spatial orientation. The combined features of structural equivalence in the disulfide loop and a mobile C-terminal tail appear to be responsible for the activity of GI-15 as a competitive antagonist against native toxin. Electrostatic surface potential comparisons of the first disulfide region of GI-15 with other alpha-conotoxins or receptor-bound states of acetylcholine and d-tubocurarine show a common protruding surface that may serve as the minimal binding determinant for the neuromuscular acetylcholine receptor alpha 1-subunit. On the basis of the original "Conus toxin macrosite model" [Olivera, B. M., Rivier, J., Scott, J. K., Hillyard, D. R., and Cruz, L. J. (1991) J. Biol. Chem. 266, 1923-1936], we propose a revised binding model which incorporates these results.
About this Structure
1QS3 is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.
Reference
NMR solution conformation of an antitoxic analogue of alpha-conotoxin GI: identification of a common nicotinic acetylcholine receptor alpha 1-subunit binding surface for small ligands and alpha-conotoxins., Mok KH, Han KH, Biochemistry. 1999 Sep 14;38(37):11895-904. PMID:10508392
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