1XGA
ALPHA CONOTOXIN GI: 2-7;3-13 (NATIVE) DISULFIDE BOND ISOMER, NMR, 35 STRUCTURES
Summary for 1XGA
| Entry DOI | 10.2210/pdb1xga/pdb |
| Descriptor | ALPHA-CONOTOXIN GI (1 entity in total) |
| Functional Keywords | alpha-conotoxin, nicotinic acetylcholine receptor, disulfide bond isomers, toxin |
| Biological source | Conus geographus (geography cone) |
| Cellular location | Secreted : P01519 |
| Total number of polymer chains | 1 |
| Total formula weight | 1442.65 |
| Authors | Gehrmann, J.,Alewood, P.F.,Craik, D.J. (deposition date: 1998-01-18, release date: 1999-02-16, Last modification date: 2024-06-05) |
| Primary citation | Gehrmann, J.,Alewood, P.F.,Craik, D.J. Structure determination of the three disulfide bond isomers of alpha-conotoxin GI: a model for the role of disulfide bonds in structural stability. J.Mol.Biol., 278:401-415, 1998 Cited by PubMed Abstract: The three possible disulfide bonded isomers of alpha-conotoxin GI have been selectively synthesised and their structures determined by 1H NMR spectroscopy. alpha-Conotoxin GI derives from the venom of Conus geographus and is a useful neuropharmacological tool as it selectively binds to the nicotinic acetylcholine receptor (nAChR), a ligand-gated ion channel involved in nerve signal transmission. The peptide has the sequence ECCNPACGRHYSC-NH2, and the three disulfide bonded isomers are referred to as GI(2-7;3-13), GI(2-13;3-7) and GI(2-3;7-13). The NMR structure for the native isomer GI(2-7;3-13) is of excellent quality, with a backbone pairwise RMSD of 0.16 A for a family of 35 structures, and comprises primarily a distorted 310 helix between residues 5 to 11. The two non-native isomers exhibit multiple conformers in solution, with the major populated forms being different in structure both from each other and from the native form. Structure-activity relationships for the native GI(2-7;3-13) as well as the role of the disulfide bonds on folding and stability of the three isomers are examined. It is concluded that the disulfide bonds in alpha-conotoxin GI play a crucial part in determining both the structure and stability of the peptide. A trend for increased conformational heterogeneity was observed in the order of GI(2-7;3-13) DOI: 10.1006/jmbi.1998.1701 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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