Fuligo septica

Fuligo septicais a species ofslime moldin the classMyxomycetes. It iscommonlyknown asscrambled egg slimeorflowers of tanbecause of its peculiar yellowish appearance. It is also known asdog vomit slime moldand is relatively common with a worldwide distribution, often being found on barkmulchin urban areas after heavy rain or excessive watering. Theirsporesare produced on or in aerialsporangiaand are spread by wind.
The first description of the species was provided by French botanistJean Marchantin 1727, who referred to it as "fleur de tan" (bark flower); Marchant also classified it as "des éponges" (one of the sponges).Carl Linnaeuscalled itMucor septicusin his 1763Species Plantarum.The species was transferred to the genusFuligoby German botanistFriedrich Heinrich Wiggersin 1780.
Like many slime molds, the cells of this species typically aggregate to form aplasmodium, amultinucleatemass of undifferentiated cells that may move in an ameboid-like fashion during the search for nutrients.F. septica's plasmodium may be anywhere from white to yellow-gray,typically 2.5–20 cm (1.0–7.9 in) indiameter, and 1–3 cm (0.4–1.2 in) thick.The plasmodium eventually transforms into a sponge-likeaethalium, analogous to the spore-bearing fruiting body of amushroom; which then degrades, darkening in color, and releases its dark-colored spores.F. septicaproduces the largest aethalium of any slime mold.This species is known to have its spores dispersed bybeetles(familyLatridiidae).
The spores have a two-layered wall, with a dense outer layer with spines, and a fibrous inner layer. During germination, the outer layer splits to create an opening, and more elastic inner layer ruptures later as protoplasm emerges. A remnant of the inner layer may be persistent and adhere to the protoplast after it has emerged from the spore. Aperoxidaseenzyme present in the inner cell wall plays a role in germination.
Fuligo septicagrows on rotten wood and plant debris, but can also grow on the leaves and stems of living plants.
Slime molds have a high resistance to toxic levels of metals; one author was prompted to write "The levels ofzincinFuligo septicawere so high (4,000–20,000ppm) that it is difficult to understand how a living organism can tolerate them."The resistance to extreme levels of zinc appears to be unique toF. septica.The mechanism of this metal resistance is now understood:F. septicaproduces a yellowpigmentcalledfuligorubin A, which has been shown tochelatemetals and convert them to inactive forms.
ExtractsfromF. septicashowantibioticactivity againstBacillus subtilisandCandida albicans, andcytotoxicactivity on KB cells (a cell line derived from a humancarcinomaof thenasopharynx).
Fuligo septicacontains a yellowpigmentcalled fuligorubin A that is thought to be involved inphotoreceptionand in the process of energy conversion during itslife cycle.In 2011, a Japanese research group reported isolating and characterizing a newchlorine-containing yellow pigment from a specific strain of the organism that they called dehydrofuligoic acid.
In Scandinavian folklore,Fuligo septicais identified as the vomit oftroll cats.
InFinland, the mold was believed to be used by witches to spoil their neighbors' milk. This gave it the name "paranvoi"(butter of thefamiliar spirit).
Similarly, Swedish folklore labelsTremella mesentericaas the vomit of a witch's 'carrier.'
Both are referred to inDutchas "heksenboter" (witches' butter), and inLatvian"ragansviests" (witches' butter) or "raganu spļāviens" (witches' spit).
The species is known to trigger episodes ofasthmaand allergicrhinitisin susceptible people.
Intronsare sections ofDNAthat must be properly cleaved, digested and processed prior to rendering functionalmRNAsforprotein synthesis. Because it has a large number ofgroup I introns,F. septicais used as a model to understand the processing and evolution ofRNA.