Spider venom
Spider venom is a mixture of biologically active substances delivered through a spider’s bite, typically to subdue prey or deter threats.
Spider fang: A spider’s pointed mouthpart, used to pierce prey and deliver venom. Fangs puncture tissue and channel venom into the bite site.
Peptide: A short chain of amino acids joined by peptide bonds. Many potent spider toxins are small, structurally constrained peptides.
ω-Conotoxin MVIIA: A cone-snail peptide that blocks certain voltage-gated calcium channels and is used as the drug ziconotide. It illustrates a venom-derived medicine, while spider toxins remain mostly research leads.
Latrodectus: A genus of spiders that includes black widows and other widow spiders. Widow venom contains latrotoxins associated with intense pain and neurotransmitter release.
Spider silk: A protein fiber produced by spiders for webs, safety lines, and other functions. Silk is a spider secretion used for structure and capture, not injected through a bite.
Neurotoxin: A toxin that disrupts the function of nerve cells or their signaling. Many spider venom components act on ion channels or other targets in the nervous system.
Disulfide bond: A covalent bond between the sulfur atoms of two cysteine residues. Disulfide bonds stabilize the folded structures of many venom peptides.
ω-Agatoxin IVA: A peptide from the funnel-web spider Agelenopsis aperta that blocks P-type and Q-type calcium channels. This spider toxin became a precise probe for identifying neuronal calcium channels.
Atrax robustus: The Sydney funnel-web spider, a medically significant species native to eastern Australia. Its venom contains potent neurotoxins that can cause severe human envenomation.
Poison: A harmful substance that causes injury when absorbed, inhaled, ingested, or otherwise contacted. Venom is actively delivered by a bite; poison generally harms without such delivery.