Acrasin
Slime mold aggregation phermones
From Wikipedia, the free encyclopedia
An acrasin is a pheromone used by species of slime mold, which signals to the many individual cells and triggers an aggregation response, such that they form a single large cell (a plasmodium).[1] One of the earliest acrasins to be identified was cyclic AMP, found in the species Dictyostelium discoideum by Brian Shaffer, which exhibits a complex swirling-pulsating spiral pattern when forming a pseudoplasmodium.
The term "acrasin" is a reference to the character Acrasia in Edmund Spenser's Faerie Queene, who seduced men against their will and then transformed them into beasts. Acrasia is itself a play on the Greek akrasia that describes loss of free will.
Extraction
Brian Shaffer was the first to purify acrasin, now known to be cyclic AMP, in 1954, using methanol.[2] Glorin, the acrasin of Polysphondylium violaceum, can be purified by inhibiting the acrasin-degrading enzyme acrasinase with alcohol, extracting with alcohol and separating with column chromatography.[3][4]
Notes
- ^ Evidence for the formation of cell aggregates by chemotaxis in the development of the slime mold Dictyostelium discoideum - J.T.Bonner and L.J.Savage Journal of Experimental Biology Vol. 106, pp. 1, October (1947) Cell Biology
- ^ Aggregation in cellular slime moulds: in vitro isolation of acrasin - B.M.Shaffer Nature Vol. 79, pp. 975, (1953) Cell Biology
- ^ Identification of a pterin as the acrasin of the cellular slime mold Dictyostelium lacteum - Proceedings of the National Academy of Sciences United States Vol. 79, pp. 6270–6274, October (1982) Cell Biology
- ^ Hunting Slime Moulds - Adele Conover, Smithsonian Magazine Online (2001)