Mipartoxin-I, a novel three-finger toxin, is the major neurotoxic component in the venom of the redtail coral snake Micrurus mipartitus (Elapidae).

摘要: The major venom component of Micrurus mipartitus, a coral snake distributed from Nicaragua to northern South America, was characterized biochemically and functionally. This protein, named mipartoxin-I, is novel member the three-finger toxin superfamily, presenting characteristic cysteine signature amino acid sequence length short-chain, type-I, α-neurotoxins. Nevertheless, it varies considerably related toxins, with identity not higher than 70% in multiple alignment 67 proteins within this family. Its observed molecular mass (7030.0) matches value predicted by its sequence, indicating lack post-translational modifications. Mipartoxin-I showed potent lethal effect mice (intraperitoneal median dose: 0.06 μg/g body weight), caused clear neuromuscular blockade on both avian mouse nerve-muscle preparations, post-synaptic action through cholinergic nicotinic receptor. Since mipartoxin-I most abundant (28%) protein M. mipartitus venom, should play role toxicity, therefore represents an important target for developing therapeutic antivenom, which very scarce or even unavailable regions where inhabits. structural information here provided might help preparation synthetic recombinant immunogen overcome limited availability.