Tags: Protein.
Omega-atracotoxin is an insect-specific neurotoxin of Blue mountains funnel-web spiders whose phylogenetic specificity derives from its ability to antagonise insect but not vertebrate voltage-gated calcium channels. Two spatially proximal amino acid residues Asn(27) and Arg(35) form a contiguous molecular surface that is essential for toxin activity. It has been proposed that this surface of the beta-hairpin is a key site for interaction of the toxin with insect calcium channels.