 Structures
of several conotoxins which have been used as research tools for studying ion channel
function. Click on each image to access a molecular model of the conotoxin derived
from its empirically derived 3D structure. To manipulate these images you must have Chime or RasMol. Chime is a Netscape and
Internet Explorer 4 browser plugin which allows you to view 3D structures online. The
rendered image can be rotated and viewed in any format (wire-frame, ball-and-stick, space
filling) and particular features displayed (eg. disulfide bonds, hydrogen bonds , etc). If
you have not already done so, download
Chime plugin from MDL, (or download
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Alpha-conotoxin PnIa: This is
a selective blocker of the neuronal-type nicotinic receptor, a member of the ligand-gated
ion channel family. It is from the cone snail Conus pennaceus. Reference: Hu SH, Gehrmann J, Guddat LW, Alewood PF, Craik
DJ, Martin JL (1996) The 1.1 A crystal structure of the neuronal acetylcholine receptor
antagonist, alpha-conotoxin PnIA from Conus pennaceus. Structure. 4: 417-423.
To link to original references documenting the
determination of the 3D structure of alpha-conotoxin PnIa (PDB Id: 1PEN) click here |
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Omega-conotoxin MVIIa (SNX-111, Ziconotide):
This is a selective blocker for N-type calcium channels. It is from the cone snail Conus
magus and contains a short triple stranded antiparallel beta sheet. Reference: Kohno, T, Kim, J.I., Kobayashi, K., Kodera, Y.,
Maeda, T. and Sato, K. (1995) Three-dimensional structure in solution of the calcium
channel blocker omega-conotoxin MVIIA. Biochemistry. 34: 10256-10265.
To link to the original references documenting the
determination of the 3D structure (PDB Id: 1OMG) click here. |
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Omega-conotoxin MVIIc: This
is a selective blocker for P-type calcium channels. It is from the cone snail Conus
magus. Reference: Farr-Jones S,
Miljanich G.P., Nadasdi L., Ramachandran J, and Basus V.J. (1995) Solution structure of
omega-conotoxin MVIIC, a high affinity ligand of P-type calcium channels, using 1H NMR
spectroscopy and complete relaxation matrix analysis. J Mol Biol. 248: 106-124.
To link to the original references documenting the
determination of the 3D structure (PDB Id: 1OMN) click
here. |
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mu-conotoxin Giiib: This cone
snail derived toxin (from Conus geographus) is a specific blocker of skeletal
sodium channels. Its folding is similar to scorpion toxins and insect defensins. Its
structure is stabilized by 3 disulfide bonds. Reference:
Hill, J.M., Alewood,P.F. and CraikD.J. (1986) Three-dimensional solution structure of
mu-conotoxin GIIIB, a specific blocker of skeletal muscle sodium channels. Biochemistry
3: 8824-8835.
To link to original references documenting the
determination of mu-conotoxin's 3D structure (PDB Id: 1GIB) click
here. |
For structures of
OTHER CONOTOXINS, see list updated 26/12/'98 Conotoxin Structures in the Protein Data Base
For structures of
OTHER ION CHANNEL TOXINS, see J.Christian Hesketh's Ion Channels and Toxins HomePage.
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