Snake toxins belong to a family of proteins [1,2,3] which groups short and
long neurotoxins, cytotoxins and short toxins, as well as a other miscellanous
venom peptides. Most of these toxins act by binding to the nicotinic
acetylcholine receptors in the postsynaptic membrane of skeletal muscles and
prevent the binding of acetylcholine, thereby blocking the excitation of
Snake toxins are proteins that consist of sixty to seventy five amino acids.
Among the invariant residues are eight cysteines all involved in disulfide
bonds. A signature pattern was developed  which includes four of these
cysteines as well as a conserved proline thought to be important for the
maintenance of the tertiary structure. The second cysteine in the pattern is
linked to the third one by a disulfide bond.
May 2004 / Text revised.
PROSITE method (with tools and information) covered by this documentation:
Classification of elapid snake neurotoxins and cytotoxins according to chain length: evolutionary implications.
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