Difference between revisions of "Panaeolus cyanescens"
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Edited by students of [mailto:firstname.lastname@example.org Jennifer Talbot] for [http://www.bu.edu/academics/cas/courses/cas-bi-311/ BI 311 General Microbiology], , [http://www.bu.edu/ Boston University].
[[Category:Pages edited by students of Jennifer Talbot at Boston University]]
[[Category:Pages edited by students of Jennifer Talbot at Boston University]]
Revision as of 15:43, 10 December 2018
a. Higher order taxa
Domain: Fungi, Phylum: Basidiomycota, Class: Agaricomycetes, Order: Agaricales, Family: Panaeolus, Genus: P. cyanescens
Panaeolus cyanescens is a fungal species found all over the world, including islands in Oceania, Australia, Europe, and North and South America (1,2). Most notably, it naturally contains the two psychoactive compounds psilocybin and psilocin (the former being a phosphorylated version of the latter) which produce intense sensory, mood, and thought experiences culminating in an altered state of consciousness in humans (3). For this reason, P. cyanescens is often used as a recreational drug, or “magic mushroom”, although psilocybin and psilocin are both controlled substances in many countries (4). P. cyanescens has the potential to play an integral role in psychotherapy and neuropharmacology in treatment of various psychological disorders (5). Other than fitness advantages in the dung and wood decay niche environment, it is unclear what evolutionary advantages the fungus might have obtained from producing psilocin (5). There is limited information on the genomic structure of P. cyanescens.
3. Genome structure
Little is known about the genome structure of P. cyanescens. It has a genome size of approximately 45 Mbp and expresses more than 13,000 different proteins (12). wThe genes that code for the enzymes that allow for biosynthesis of urea are thought to have arisen from horizontal gene transfer of metabolic gene cluster (12). Some unique proteins coded for in the mushroom are tryptophan decarboxylases that produce psilocin (12). As of current research, the chromosome number of P. cyanescens is unknown.
4. Cell structure & Morphology
P. cyanescens has a pale gray or brownish convex cap varying from 1.5 cm - 4 cm in diameter (4). The mushroom has a smooth or cracked surface texture. The whitish colored stem is smooth and can grow up to 70mm (4). At the microscopic level, P. cyanescens has parallel hyphae, and gills underneath the cap. It contains black, non-transparent, elliptical spores with a size of up to 14 ×10 μm (4).
5. Metabolic Processes
Due to its reputation as a psychoactive mushroom, much of the research on the metabolism of P. cyanescens deals with its production of psychoactive compounds. The mushroom contains tryptophan and tryptamine precursors to psilocin and serotonin located in its fruiting bodies, and is able to produce urea to metabolize toxic ammonia (2). All strains of P. cyanescens contain psilocin, but some strains (those from Australia and Thailand) have a negligible or nonexistent psilocybin content. The mushroom is an inamyloid, meaning it does not contain starch (4). Psilocin and psilocybin production is a relatively simple process, comprising 5 enzymatic steps and 4 enzymes that use L-tryptophan as the basis for synthesis. The end result of this process is the formation of psilocybin, some of which is intracellularly dephosphorylated into psilocin - a reversible process within the cell (8). There is competing evidence as to whether or not psilocin or psilocybin is the dominant species within P. cyanescens, although current research suggest such rations might be strain based (4,8).
P. cyanescens is found in both tropical and subtropical regions primarily Australia, Europe, North America, South America, and islands of Oceania (6). P. cyanescens requires specific conditions for optimal growth. A pH of 8, the presence of oxygen, and the absence of light are needed for the mushroom to grow to a large diameter (7). P. cyanescens is coprophilous or a dung inhabiting species (6). Carabao dung and cow dung are an ideal habitat for P. cyanescens growth because the fungus can colonize rapidly in this environment (7). In this media, the mushroom also produces the most fruiting bodies because mushroom its ability to obtain water and nutrients from the dung and the leftover minerals from the animal's digestive tract (7).
P. cyanescens contains high psilocybin and psilocin concentrations, which can reach up to 0.2% and 0.6%, respectively, by dry weight in some strains, but concentrations of these compounds vary from mushrooms sampled around the world (2). Both psilocybin and psilocin are hallucinogenic compounds which, upon consumption, can cause an altered state of consciousness as well as other hallucinogenic effects that include but are not limited to changes to the visual field, mood, perception of color, and feelings of euphoria (2, 9). P. cyanescens has been shown to have three times the psilocin and psilocybin content than that of the more common recreational variety of hallucinogenic mushroom, Psilocybe cubensis (10). Due to it’s high psilocin content, P. cyanescens is found to be potent with the onset of hallucinogenic effects occurring soon after ingestion (2).
8. Current Research
Current research focuses on the effects of psilocin and psilocybin on psychological disorders. Psilocybin is structurally very similar to the neurotransmitter serotonin, the hormone melatonin, and N,N-Dimethyltryptamine, all endogenous compounds in the human body, and is neuropsychologically relevant for its possible therapeutic purposes (11,9). There have been a handful of studies that researched the hallucinogenic effects on humans of the compound psilocybin, found in P. cyanescens and various other psychedelic fungi. A recent study tracked the effects of the compound on individuals with treatment resistant depression (12). This was done through functional magnetic resonance imaging (fMRI) and analysis of the cerebral blood flow to various regions of the brain before and after treatment with psilocybin (12). The amygdala, or the processing center for various emotions such as fear and anxiety, decreased in activity which led to an improvement in symptoms of depression, while the default mode network - a collaboration of different cranial regions - became more stable. The results of this study have shown that psilocybin seem to ‘reset’ the brain, thus alleviating symptoms of depression (12). Other research focuses on establishing the genetic mechanism and pathway for psilocybin production in P. cyanescens in order to replicate its production synthetically for its therapeutic effects (13). Preliminary studies have have shown potential for psilocybin to treat obsessive compulsive disorder, tobacco and addiction, and major depressive disorder (9).
(1) Allen, John W. Ethnomycological Journals: Sacred Mushroom Studies. Exotic Forays, 2009. (2) Bustillos, R. G., Dulay, R. M. R., Kalaw, S. P., Reyes, R. G., 2014. Optimization of culture conditions for mycelial growth and basidiocarp production of Philippine strains of Panaeolus antillarium and Panaeolus cyanescens. Mycosphere 5:398-404 (3) Carbonaro, T. M., & Gatch, M. B. (2016). Neuropharmacology of N,N-dimethyltryptamine. Brain research bulletin, 126(Pt 1), 74-88. (4) Carhart-Harris, Robin L, et al. Psilocybin for Treatment-Resistant Depression: FMRI-Measured Brain Mechanisms. Nature News, Nature Publishing Group, 13 Oct. 2017. (5) Dos Santos Silva-Filho, A., Seger, C. and Cortez, V. 2018. The Neurotropic Genus Copelandia (Basidiomycota) in western Parana State, Brazil. Revista Mexicana De Biodiversidad 89:15-21. (6) Fricke, J., Blei, F., & Hoffmeister, D. (2017). Enzymatic Synthesis of Psilocybin. Angewandte Chemie International Edition, 56(40), 12352–12355. (7) Geiger, H.A., Wurst, M.G., and Daniels, R.N. (2018). DARK Classics in Chemical Neuroscience: Psilocybin. ACS Chemical Neuroscience 9, 2438–2447. (8) Guzmán G., Allen J.W., Gartz J. (1998). A worldwide geographical distribution of the neurotropic fungi, an analysis and discussion Annali del Museo civico di Rovereto (14): 189–280. (9) Laussman, T., Meier-Giebing, S. 2009. Forensic analysis of hallucinogenic mushrooms and khat (Catha edulis FORSK) using cation-exchange liquid chromatography. Forensic Science International. (10) Musshoff F., Madea B., Beike J. 2000. Hallucinogenic Mushrooms on the German Market — Simple Instructions for Examination and Identification. Forensic Science International 113.1 (2000): 389-95. Web. (11) Pokorny, T., Preller, K. H., Kraehenmann, R., & Vollenweider, F. X. 2016. Modulatory effect of the 5-HT1A agonist buspirone and the mixed non-hallucinogenic 5-HT1A/2A agonist ergotamine on psilocybin-induced psychedelic experience. European Neuropsychopharmacology, 26(4), 756–766. (12) Reynolds, H., Vijayakumar, V., Gluck‐Thaler, E., Korotkin, H., Matheny, P., & Slot, J. (2018). Horizontal gene cluster transfer increased hallucinogenic mushroom diversity. Evolution Letters, 2(2), 88-101. (13) Stijve T. 1992. Psilocin, psilocybin, serotonin and urea in Panaeolus cyanescens from various origin. Persoonia. (14) Panaeolus cyanescens [Digital image]. (2010, January 11). Retrieved November 25, 2018, from https://commons.wikimedia.org/wiki/File:Panaeolus-cyanescens.jpg