Abstract:
The amino acid sequence of the first neurotoxic phospholipase A2, acanthoxin AI,
purified from the venom of the Common death adder (Acanthophis antarcticus) was
determined. Acanthoxin Al shows high homology with other Australian elapid PLA2
neurotoxins, in particular Acanthin -I and -II, also from Death adder, Pseudexin A from
the Red-bellied black snake (Pseudechis porphyriacus), and Pa-I2a and Pa-9c from the
King brown snake (Pseudechis australis). Acanthoxin Al is a single-chain 118 amino acid
residue PLA2, including 14 half cystine residues and the essential residues forming the
ubiquitous calcium binding pocket and catalytic site. Critical analysis of the residues
hypothesized to be important for neurotoxicity is presented.
