From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Anatoxin-a(S) skeletal.svg
IUPAC name
3D model (JSmol)
Molar mass 252.211 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Anatoxin-a(S) "Salivary"[a] is a naturally occurring cyanotoxin commonly isolated from cyanobacteria (specifically of the genus Anabaena) and causes excess salivation in mammals via inhibition of acetylcholinesterase.[1] Anatoxin-a(S) is structurally a cyclic N-hydroxyguanine organophosphate with a phosphate ester moiety.

Toxicity and treatment[edit]

The main mechanism of action for anatoxin-a(S) is by irreversibly inhibiting the active site of acetylcholinesterase leading to excess acetylcholine in the parasympathetic and peripheral nervous systems; inducing poisoning via nicotinic and muscarinic cholinergic receptor stimulation.[2] Treatment of afflicted case by atropine has attested to suppress the muscarinic mediated toxicity; which prevents the namesake salivation that similarly reacts to prevent the toxin's other poisoning symptoms which include lacrimation, urinary incontinence and defecation. Atropine will not, however, counter another mechanism of the compounds toxicity as it also mediates a nicotinic adverse toxicity affecting muscle tremors, fasciculation, convulsions and respiratory failure.[citation needed]

See also[edit]

  • Anatoxin-a – a cyanotoxin with an almost identical name that shares near to same active mechanism and also relates to same cyanobacteria genera but with different chemical structure


  1. ^ "Anatoxin-a".
  2. ^ Hyde, E. G.; Carmichael, W. W. (1991). "Anatoxin-a(s), a naturally occurring organophosphate, is an irreversible active site-directed inhibitor of acetylcholinesterase (EC". Journal of Biochemical Toxicology. 6 (3): 195–201. doi:10.1002/jbt.2570060305. PMID 1770503.
  1. ^ (The "(S)" its name stands for 'salivary' indicating its manner of affliction to distinguish it from a toxin having otherwise the same conventional name. cf. "See also" for aforementioned compound of shared nomenclature.)