Ponera toxin

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Poneratoxin (three-dimensional model of the protein registered with 1g92 code)

Poneratoxin ( POTX ) is the neurotoxin of ants generic Paraponera with the type 24-hour ant ( Paraponera clavata ), and the genus Dinoponera as Dinoponera longipes from the tropical rainforest South and Central America. It is administered through a poison sting and is considered to be particularly painful without causing tissue damage.

Venomous sting of a Dinoponera

composition

Poneratoxin is a pentacosa peptide , a neuropeptide . It is soluble below pH 4.5.

The poison is in a poisonous bladder as an inactive precursor , consisting of an amino acid sequence of 25 amino acids.

Poisonous effect

Poneratoxin is a powerful but slow acting agonist of smooth muscle . It first binds to cell walls and blocks synaptic transmissions in the insect's nervous system and, depending on the voltage, influences sodium ion channels in the central nervous system. It affects axons from insects as well as skeletal muscles from frogs and rats.

The 24-hour ant uses poneratoxin to paralyze prey or repel attackers. In humans, the extremely painful bite can cause fever, cold sweats and cardiac arrhythmias ; it is known as the most painful insect bite ever. According to the sting pain index ( Schmidt Sting Pain Index ) of the US entomologist Justin O. Schmidt , which describes the severity of pain on a scale from 1.0 to 4.0+, the insect is 4.0+. The pain is often described as being burned alive. They subside after about 24 hours - hence the name of the ant. Immediate treatment of the sting with ice water and subsequent intake of Benadryl capsules ( diphenhydramine , an antihistamine) alleviates the pain.

The toxic effect does not leave any permanent damage in the tissue.

Applications by humans

Sources of ponera toxin

Chemically synthesized poneratoxin is just as effective as natural or recombinant . Baculovirus was used as the vector for recombination . Synthetic PoTX is often used for biochemical studies. Clinical application possibilities and the use as an insecticide are explored.

Use in rituals

The giant ants are part of an initiation ritual for an indigenous group of people in South America , the Sateré-Mawé , who live in the border area between the Brazilian states of Pará and the Amazon . To do this, numerous ants are put into a glove made of plant fibers, which the boy then has to wear on his hand for almost 30 minutes. This rite is considered a test of courage  - boys who endure the pain of the stings can achieve leadership positions in the tribe. To earn this respect, this process must first be repeated up to 25 times in the boy's life.

Individual evidence

  1. ↑ a b c d e f Tom Piek, Alain Duval, Bernard Hue, Henk Karst, Bruno Lapied, Piet Mantel, Terumi Nakajima, Marcel Pelhate, Justin O. Schmidt: Poneratoxin, a novel peptide neurotoxin from the venom of the ant, Paraponera clavata. In: Comparative Biochemistry and Physiology Part C: Comparative Pharmacology 99, No. 3, 1991, pp. 487-495, doi : 10.1016 / 0742-8413 (91) 90276-Y .
  2. ↑ a b c d e f Ewa Szolajska, Jaroslaw Poznanski, Miguel López Ferber, Joanna Michalik, Evelyne Gout, Pascal Fender, Isabelle Bailly, Bernard Dublet, Jadwiga Chroboczek: Poneratoxin, a neurotoxin from ant venom In: European Journal of Biochemistry Volume 271 , No. 11, June 2004, pp. 2127-2136, doi : 10.1111 / j.1432-1033.2004.04128.x .
  3. ↑ a b Vidal Haddad Junior, João Luiz Costa Cardoso, Roberto Henrique Pinto Moraes: Description of an injury in a human caused by a false tocandira (Dinoponera gigantea, Perty, 1833) with a revision on folkloric, pharmacological and clinical aspects of the giant ants of the genera Paraponera and Dinoponera (sub-family Ponerinae). Revista do Instituto de Medicina Tropical de São Paulo, vol. 47, no.4, São Paulo, July / Aug. 2005 article (Portuguese, English).
  4. ↑ Justin O. Schmidt, MS Blum and WL Overal: Hemolytic activities of stinging insect venoms. Arch. Insect Biochem. Physiol., 1, 1984, pp. 155-160.