Solution structure of ω-conotoxin MVIIA using 2D NMR spectroscopy

The solution structure of ω-conotoxin MVIIA (SNX-111), a peptide toxin from the fish hunting cone snail Conus magus and a high-affinity blocker of N-type calcium channels, was determined by 2D NMR spectroscopy. The backbones of the best 44 structures match with an average pairwise RMSD of 0.59 angstroms. The structures contain a short segment of triple-stranded β-sheet involving residues 6–8, 20–21, and 24–25. The structure of this toxin is very similar to that of ω-conotoxin GVIA with which is has only 40% sequence homology, but very similar calcium channel binding affinity and selectivity.