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From Proteopedia
Solution Structure of alpha-Conotoxin OmIA
Overview
alpha-Conotoxin OmIA from Conus omaria is the only alpha-conotoxin that shows a approximately 20-fold higher affinity to the alpha3beta2 over the alpha6beta2 subtype of nicotinic acetylcholine receptor. We have determined a three-dimensional structure of alpha-conotoxin OmIA by nuclear magnetic resonance spectroscopy. alpha-Conotoxin OmIA has an "omega-shaped" overall topology with His(5)-Asn(12) forming an alpha-helix. Structural features of alpha-conotoxin OmIA responsible for its selectivity are suggested by comparing its surface characteristics with other functionally related alpha4/7 subfamily conotoxins. Reduced size of the hydrophilic area in alpha-conotoxin OmIA seems to be associated with the reduced affinity towards the alpha6beta2 nAChR subtype.
About this Structure
Full crystallographic information is available from OCA.
Reference
Solution conformation of a neuronal nicotinic acetylcholine receptor antagonist alpha-conotoxin OmIA that discriminates alpha3 vs. alpha6 nAChR subtypes., Chi SW, Kim DH, Olivera BM, McIntosh JM, Han KH, Biochem Biophys Res Commun. 2006 Jun 23;345(1):248-54. Epub 2006 Apr 27. PMID:16678128 Page seeded by OCA on Sun May 4 04:57:49 2008
