Abstract

Fuligo septica, which is also known as the dog vomit slime mold or scrambled slime belongs to the class myxomycetes. It is abundantly found in a varied number of terrestrial ecosystems, especially in area with higher water content. Fuligo septica exist as a colorful mass between 2-20 cm (length) and 1-3 cm (thickness).

Fuligo Septica Dog vomit slime mold

Fuligo septica is a slime mold, also commonly known as dog vomit slime mold or scrambled egg slime. The common name for Fuligo septica has originated from its physical appearance. It appears as bile- colored yellow molds on mulch or tree barks at some point in their life cycle. It is a commonly found species of slime mold spread across the eastern and mid-western region of the US and is commonly seen growing on mulch and trees.
The scientific classification of Fuligo septica can be described as Kingdom: Protists, Phylum: Myxomycota, Order: Physarales, Family: Physaraceae, Class: Myxomycetes, Genus: Fuligo. Organisms that utilize spores for reproduction are broadly classified as belonging to a family of “slime molds”. These organisms in at least one phase of their lifecycle have a gelatinous slime like appearance. Organisms belonging to the class myxomycetes including the Fuligo septica undergo two phases in their life cycles. In the first phase the organism is uninucleate, however during the growth phase the molds exist as multinuclear plasmodium aggregate form. The plasmodium is an undifferentiated multinuclear cellular mass. These undifferentiated mass of cells are simply mass of cytoplasm as they lack a well defined cellular wall. They tend to swallow up/phagocytose food from bacteria or other molds with their amoeboid like movement as they crawl over the food sources. ( Dembitsky, Rˇezanka, Spı´zˇek, & O Hanus, 2005).
The mode of propagation in Fuligo Septica is by aerial transmission of sponge. The plasmodium of the Fuligo Septica is converted to a specialized structure called aethalium. The aethalium bear the spores of the mold that are eventually dispersed by beetles. The aethalium, unlike the plasmodium are protected by a cell wall known as ‘peridium’. It has been suggested that the aethalium of Fuligo septic are the largest spore producing bodies among the various kinds of slime molds.
A unique feature of the Fuligo Septica plasmodia is their tendency to accumulate late amount of zinc. In a study published in Journal of Environmental Quality 2002, researchers collected samples of molds from two locations in Russia and North Korea. The weight of the biomass ranged from 305-968 mg. However, what was observed was nothing short of astonishing. The amount of Zinc accumulated in the samples ranged from 8400 -23000 mg/kg of the dry weight of the biomass. The mold samples were collected from a number of sources, such as tree barks, old buildings, rocks and other structures. Samples from all these locations had elevated Zn levels (4,000–20,000 ppm). The authors wonder in the article as to” how an organism survives the high levels”. The ability of the Fuligo septica to tolerate very high Zn levels stems from the presence of yellow pigments called fuligorubin (a polyene pigment) that chelate with the free metal and convert them to inactive form. Fuligorubin is also believed to be involved in energy conversion during the life cycle.( Zhulidov, Robarts, Zhulidov, Zhulidova, Markelov, Rusanov, & Headley, 2002)
In addition to fuligorubin, Fuligo Septica synthesizes amino acids, dienoic and polyenoic faty acids, lipids, amides and glycosides (Dembitsky et al. 2005). There has been one report so far describing the presence of biologically active compounds derived from this mold species. It was demonstrated that extract from the Fuligo septica possessed antibiotic activity against candida albicans and bacillus subtilis. In the same study it was reported that the Fuligo extract demonstrated inhibition of growth of cells isolated from a form of nasopharyngeal cancer. Crude extract from the mold were used in the study. A recent study published in 2011 demonstrates the characterization of a new chlorine containing compound isolated from Fuligo septica. The compound is called dehydrofugaloic acid and is a yellow pigment. (Shintani, Toume, Yamamoto, Ishibashi, 2011). A report presented by Connecticut department of agriculture states that Fuligo septica are not pathogenic to plants. There has been one study demonstrating the pathogenicity of the spores of Fuligo septica on humans. Dialyzed spore extracts were prepared from a number of slime mold including the Fuligo septica. Intradermal testing was performed on patients with asthma and tinnitis. Exposure to the mold extracts in patients with asthma generated “immediate skin reaction” while patients with rhinitis demonstrated ‘late stage sensitivity’. A study involving extracts from individual mold species would provide information about pathogenic nature of Fuligo septica ( Santilli, Rockwell, & Collins, 1985).
Fuligo septica have 12 group I introns (four in the small subunit and eight in the large subunit ribosomal RNAs) in their ribosomal DNA region. Introns are the unnecessary nucleotide sequences present between exons (actual mRNA transcript) that are removed by splicing. Splicing is a complex process that requires a high degree of precision. With its 12 group I introns, Fuligo septica was used as a model to understand and study the process of slicing and RNA evolution. (Lundblad, Einvik, Rønning, Haugli, Johansen, 2004).
Fuligo septica is a slime mold belonging to the class Myxomycetes. It occurs as a uninucleate organism first, however the multinucleate plasmodium form is involved in propagation and other unique physiological functions. It is usually recognized due to its bright yellow hue; however it also exists in other colors. It presents some unique morpho-physiological and biochemical characteristics. These slime molds are present abundantly in terrestrial environment especially in area with higher water content.

References

Dembitsky, V.M., Rˇezanka, T., Spı´zˇek, J., & O Hanus, L., (2005). Secondary metabolites of the Slime Molds. Phytochemistry 66 747–769
Latowski, D., Lesiak, A., Jarosz-Krzeminska, E., & Strzalka, K. (2008). "Fuligo septica, as a new model organism in studies on interaction between metal ions and living cells". Metal Ions in Biology and Medicine and Medicine 10: 204–9
Lundblad EW, Einvik C, Rønning S, Haugli K, Johansen S. (2004). Twelve Group I introns in the same pre-rRNA transcript of the myxomycete Fuligo septica: RNA processing and evolution. Mol Biol Evol. 21(7):1283-93.
Santilli, J.,Rockwell, W.J., Collins, R.P (1985). The significance of the spores of the Basidiomycetes (mushrooms and their allies) in bronchial asthma and allergic rhinitis. Ann Allergy. 3:469-71.
Shintani A, Toume K, Yamamoto Y, Ishibashi M. (2010). "Dehydrofuligoic acid, a new yellow pigment isolated from the myxomycete Fuligo septica f. flava". Heterocycles 82 (1): 839–42.
Zhulidov, D.A., Robarts, R.D., Zhulidov, A.V., Zhulidova, O.V., Markelov, D.A., Rusanov, V. A., & Headley, J.V. (2002). Zinc accumulation by the slime mold Fuligo septica (L.) Wiggers in the former Soviet Union and North Korea. J Environ Qual. 31(3):1038-42.