Home • Pholiota conissans CIRM-BRFM 674 v1.0
Picture from Régis Courtecuisse, Lille University, France
Picture from Régis Courtecuisse, Lille University, France

Pholiota conissans (Fr.) M.M. Moser [= Ph. graminis (Quél.) Singer] is a fungus belonging to the Strophariaceae family within the Agaricoid clade of the order Agaricales (Matheny et al., 2006). It is an uncommon fungus that usually grows on plant debris of monocotiledoneous herbaceous plants inhabiting wetlands such as Juncus, Scirpus, Thypha and Phragmites. Less frequently, it can also be found fruiting on decayed wood of trees of humid zones such as Salix and Alnus. Ph. gummosa (Lasch) Sing. is a very similar species in microscopic and macroscopic features and the Ph. conissans strain (CIRM-BRFM 674), selected for genome sequencing at JGI within the CSP15-1609 project, could constitute a taxonomic complex that would include Ph. gummosa and some other Ph. conissans strains. However, Ph. conissans can be distinguished from Ph. gummosa in habitat and lifestyle. The latter is a common and widespread white-rot wood fungus that usually fruits on hardwoods or, less frequent, on softwoods. In spite of the above mentioned habitat preferences, species identification of Pholiota has been traditionally considered a difficult matter where different studies based on microscopic features (Smith & Hesler, 1968), biosytematics (Farr et al., 1977) and cultural aspects (Jacobsson, 1989; Klan et al., 1989), are required.

Since no members of the genus Pholiota were previously sequenced at JGI, Ph. conissans, together with Ph. alnicola (Fr.) Sing., has been proposed for genome sequencing in the CSP15-1609 project within a total of 16 new genomes of Agaricales. The genome sequence of the leaf litter degrading fungus Ph. conissans will allow to compare its lignocellulolytic enzymes with those of the wood-rotting fungus Ph. alnicola.

The litter decomposing fungi (that usually grow on plant debris in soils), would be attractive for removal and mineralization of polycyclic aromatic hydrocarbons (PAHs), which are one of the most frequent organopollutants of soils. In this way, Pholiota sp. was found to remove a mixture of different PAHs, such as anthracene, pyrene and benzo(a)pyrene (BaP). This fungus degrades almost completely BaP and more than 60% and 70% of the pyrene and anthracene respectively in Mn(II) supplemented cultures (Steffen, et al., 2002). Furthermore, the closely related white-rot wood fungus Kuehneromyces mutabilis (Scop.) Sing & A. H. Smith [=Ph. mutabilis (Schaeff.) P. Kumm.], was reported to be promising for biotechnological application because of its ability to decolorize azo (Acid Red 183) and anthraquinonic (Basic Blue 22) dyes (Jarosz-Wilkolazka et al., 2002).

References

Farr, E. R., Miller, O.K. Jr. & Farr, D. F. (1977). Biosystematic studies in the genus Pholiota, stirps Adiposa. Canad. J. Bot. 55: 1167-1180.

Jacobsson, S. (1989). Studies on Pholiota in culture. Mycotaxon 36: 95-145.

Jarosz-Wilkolazka, A., Kochmanska-Rdest, Malarczyk, E., Wardas, W. and Leonowicz, A. (2002). Fungi and their ability to decolourize azo and antrhaquinonic dyes. Enzyme and Microbial Technology 30: 566-572.

Klan, J., Baudisova, D. and Rulfova, I. (1989). Cultural, enzymatic and cytological studies in the genus Pholiota. Mycotaxon 36: 249-271.

Matheny, P.B., Curtis, J.M., Hofstetter, V., Aime, M.C., Moncalvo, J.M., Ge, Z.W., Yang, Z.L., Slot, J.C., Ammirati, J.F., Baroni, T.J., Bougher, N.L., Hughes, K.W., Lodge, D.J., Kerrigan, R.W., Seidl, M.T., Aanen, D.K., DeNitis, M., Daniele, G.M., Desjardin, D.E., Kropp, B.R., Norvell, L.L., Parker, A., Vellinga, E.C., Vilgalys, R., Hibbett, D.S., 2006. Major clades of Agaricales: a multilocus phylogenetic overview. Mycologia 98, 982-995.

Smith, A. H. & Hesler, L. R. (1968). The North American Species of Pholiota. New York: Hafner. 402 pp.

Steffen, K.T., Hattaka, A. and Hofrichter, M. (2002). Removal and mineralization of polycyclic aromatic hydrocarbons by litter-decomposing basidiomycetous fungi. Appl. Microbiol. Biotechnol. 60: 212-217.