Supplement to Mycologia Vol. 60(5) October 2009 Newsletter of the Mycological Society of America — In This Issue — Feature Article Fungal zoospores are valuable food Fungal zoospores are valuable food resources in aquatic ecosystems resources in aquatic ecosystems MSA Business President’s Corner By Frank H. Gleason, Maiko Kagami, Secretary’s Email Express Agostina V. Marano and Telesphore Simi-Ngando MSA Officers 2009 –2010 MSA 2009 Annual Reports Fungal zoospores are known to contain large quantities Minutes of the 2009 MSA Annual Council Meeting Minutes of the MSA 2009 Annual Business Meeting of glycogen and lipids in the form of endogenous reserves. MSA 2009 Award Winners Lipids are considered to be high energy compounds, some of MSA 2009 Abstracts (Additional) which are important for energy storage. Lipids can be con - Mycological News A North American Flora for Mushroom-Forming Fungi tained in membrane bound vesicles called lipid globules Marine Mycology Class which can easily be seen in the cytoplasm of fungal Mycohistorybytes Peripatetic Mycology zoospores with both the light and electron microscopes Student Research Opportunities in Thailand (Munn et al . 1981; Powell 1993; Barr 2001). Koch (1968) MSA Meeting 2010 MycoKey version 3.2 and Bernstein (1968) both noted variation in the size and MycoRant numbers of lipoid globules within zoospores in the light mi - Dr Paul J Szaniszlo croscope. The ultrastructure of the lipid globule complex Symposium : Gondwanic Connections in Fungi Mycologist’s Bookshelf was carefully examined by Powell and Roychoudhury A Preliminary Checklist of Micromycetes in Poland (1992). Fungal Pathogenesis in Plants and Crops Pathogenic Fungi in the Cryphonectriaceae Preliminary studies reviewed by Cantino and Mills Recently Received Books (1976) revealed a rich supply of lipids in the cells of Blasto - Take a Break cladiella emersonii . Since then, the chemical composition of Hooked on Marine Mycology Veggie Kabobs lipids, including both fatty acids and sterols, has been char - Mycological Classifieds acterized in a number of genera of zoosporic fungi, in the Mold testing and identification services Mycological Jobs Blastocladiomycota and Chytridiomycota by Southall et al. Postdoctoral Research Associate - Plant and Microbial Ecology (1977) and Wheete et al . (1989) and in the Neocalli - Ph.D. Graduate Research Assistant - Plant and Microbial Ecology mastigomycota by Kemp et al . (1984) and Koppová et al . Graduate Research Assistantship in Mycology Mycology On-Line (2008). Calendar of Events The roles of lipids in the intermediary metabolism have Sustaining Members been studied by Cantino and his colleagues during different — Important Dates — stages of development in B. emersonii . As part of their re - November 15, 2009 search they found that endogenous reserves were consumed Deadline for submission to Inoculum 60(6) October 26-30, 2009 during the motile phase of the zoospores (Suberkropp & Fungal Conservation: science, infrastructure and politics Cantino 1973). We must assume that endogenous reserves Whitby, North Yorkshire , UK are also consumed by zoospores of other genera since ex - November 15-19, 2009 Asian Mycological Congress (AMC2009) & ogenous substrates are often absent from the external envi - XIth International Marine and Freshwater Mycology ronment. These reserves presumably provide energy for the Symposium (IMFMS) National Museum of Natural Science, Taichung, Taiwan movement of flagella during the motile phase which can last November 26-29, 2009 for up to several hours. Later we would expect these re - NAMA/GSMS Foray serves to provide energy for the fungi during attachment and Lafayette, LA December 6-10, 2009 germination of zoospores on the appropriate substrates. X International Fungal Biology Conference There is evidence that the total lipid content of B. emersonii Ensenada, Mexico February 15-19, 2010 zoospores decreases quickly after germination (Smith & Sil - Gondwanic Connections in Fungi Symposium verman 1973), but changes in lipid composition during the Bariloche, Argentina life cycle of other fungi have not been studied. There are other significant functions for the high energy Editor — Jinx Campbell Dept. of Coastal Sciences, Gulf Coast Research Lab compounds found in fungal zoospores, especially as food re - University of Southern Mississippi sources for other organisms. For example, anaerobic 703 East Beach Drive, Ocean Springs, MS 39564 Telephone: (228) 818-8878, Fax: (228) 872-4264 Continued on following page Email: [email protected] zoosporic fungi in the rumen and hind gut of herbivo - The upper size limit of most of the free-living HF rous mammals provide lipids which are known to be cells is approximately 5 µm in diameter which is important for the nutrition of the host animals (Kemp about the size of many fungal zoospores. However, et al. 1984). Cantino and Mills (1976) noted that the many of the microbes in the HF group have not been cells of Blastocladiella emersonii contain a rich sup - correctly identified (Lefèvre et al. 2007). The use of ply of carbohydrates, proteins, lipids and nucleic acids molecular methods, mainly environmental rDNA in their cytoplasm. This is undoubtedly true for all PCR for cloning and sequencing, has revealed many zoosporic fungi. For this reason we would expect fun - species of zoosporic fungi in pelagic ecosystems gal zoospores to be nutritious food items for many (Lefèvre et al. 2007; 2008). Fungal zoospores along consumers in aquatic ecosystems. In this paper we with other groups of HF are now thought to play key - will focus on the roles of fungal zoospores as food re - stone roles in aquatic food webs. Previously, the sources. modes of nutrition for all HF were thought to be re - Fungal spores and hyphae in general are known to stricted to bacterivory (Strom 2000), but fungal be eaten by a large number of different consumers in zoospores are not bacterivorous (Gleason et al . 2009). both aquatic and soil ecosystems including a variety Many zoosporic fungi can grow in the laboratory of mycophagous protozoa [amoebae (Old & Dar - on minimal synthetic media containing one carbon byshire 1978), flagellates (Hekman et al . 1992) and source such as cellulose, xylan, starch or chitin along ciliates (Petz et al. 1985)], detritivores (Arsuffi & with salts containing nitrate, sulphate and phosphate Suberkropp 1989), grazers such as filter feeding zoo - and other essential minerals (Gleason et al . 2008). plankton (Kagami et al . 2004) and benthic suspension Therefore, we would expect many zoosporic fungi to feeders (Bärlocher & Brendelberger 2004). Since grow as saprobes on allochthonous (imported) plant most of these consumers do not discriminate between and animal materials in environments which are gen - food resources except by size we would expect erally poor in carbon compounds. In these environ - zoospores as well as hyphae and nonmotile spores to ments zoosporic fungi are capable of providing many be eaten by many of these consumers, although pub - organic compounds which are necessary for the lished records are lacking. Thus fungal zoospores are growth of consumers but which are otherwise un - probably involved in many different food chains available. When this happens complex food webs ap - (Gleason et al . 2008). pear. Another important ecological role for fungal The complexity of interactions in food webs re - zoospores involves trophic upgrading. Presumably sulting from parasitism can be illustrated by one ex - many consumers must obtain at least some essential ample, the genus Coelomomyces . The life cycles of nutrients from their food sources because these com - many species in this genus involve an obligate alter - pounds cannot be produced de novo . One example of nation between two hosts: various species of mosqui - trophic upgrading is found in the cladoceran Daphnia . to larva and various species of copepods or ostracods Recent research has shown that zoospores of the par - (Whisler et al . 2009). These parasites greatly impact asitic chytrid, Zygorhizidium , are quite rich in polyun - the population sizes of both hosts. Furthermore, saturated fatty acids (PUFAs) and cholesterols, which zoospores of these parasites are eaten by grazers and are important nutrients for the cladoceran zooplank - filter feeders impacting their growth rates as well. ter, Daphnia (Kagami et al . 2007). These zoospores Therefore, populations of many different organ - are found to facilitate the trophic transfer from the isms directly and indirectly benefit from the high en - inedible large diatom, Asterionella , and the growth of ergy lipids stored in fungal zoospores. Many unknown Daphnia (Kagami et al . 2007). food chains are currently being identified (Gleason et Many species of zoosporic fungi have been re - al. 2008; Lefevre et al. 2008). This adds to the com - ported as saprobes on plant and animal materials and plexity and therefore the stability of aquatic food as parasites of both prokaryotic (i.e. cyanobacteria) webs (Lafferty et al . 2008). and eukaryotic phytoplankton, flowering plants, ro - —Frank H. Gleason tifers, nematodes, microscopic crustaceans (such as School of Biological Sciences A12, University of Sydney, Sydney, NSW, 2006, Australia copepods, ostracods and cladocera) and aquatic larvae of insects (such as diptera) in aquatic ecosystems —Maiko Kagami Department of Environmental Sciences, Toho University, Miyama (Sparrow 1960; Karling 1977; Powell 1993; Shearer 2-2-1, Funabashi, 275-8510 Japan et al. 2007
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