Agatoxin

NMR structure (PDB: 1OAV​) of Omega-agatoxin IVA. The peptide backbone is depicted by a curved cartoon diagram while the amino acid side chains are represented by capped sticks. Carbon atoms are colored grey, nitrogen blue, oxygen red, and sulfur atoms yellow.

Agatoxins are a class of chemically diverse polyamine and peptide toxins which are isolated from the venom of various spiders. Their mechanism of action includes blockade of glutamate-gated ion channels, voltage-gated sodium channels, or voltage-dependent calcium channels. Agatoxin is named after the funnel web spider (Agelenopsis aperta) which produces a venom containing several agatoxins.[1] There are different agatoxins. The ω-agatoxins are approximately 100 amino acids in length and are antagonists of voltage-sensitive calcium channels and also block the release of neurotransmitters. For instance, the ω-agatoxin 1A is a selective blocker and will block L-type calcium channels whereas the ω-agatoxin 4B will inhibit voltage sensitive P-type calcium channels. The μ-agatoxins only act on insect voltage-gated sodium channels.[2]

  1. ^ Adams ME (2004). "Agatoxins: ion channel specific toxins from the American funnel web spider, Agelenopsis aperta". Toxicon. 43 (5): 509–25. doi:10.1016/j.toxicon.2004.02.004. PMID 15066410.
  2. ^ Lackie, John (2019). Nation, Brian (ed.). A Dictionary of Biomedicine. Oxford University Press. doi:10.1093/acref/9780191829116.001.0001. ISBN 978-0-19-182911-6.