Fungi - 1.pdf

Fungi from different environments Prof. dr. hab. Agnieszka Wolna-Maruwka Department of Soil Science and Microbiology  Fungi Systematics Fungi are usually classified into five divisions: Glomeromycota Chytridiomycota Zygomycota Ascomycota...

Fungi from different environments Prof. dr. hab. Agnieszka Wolna-Maruwka Department of Soil Science and Microbiology  Fungi Systematics Fungi are usually classified into five divisions: Glomeromycota Chytridiomycota Zygomycota Ascomycota Basidiomycota Anamorphic fungi - one group which is not recognized as formal taxonomic groups. The Anamorphic fungi includes all fungi which have lost the ability to sexually reproduction.  Fungi practical section: ►molds (filamentous fungi) ►yeast. The fungi are eucaryotic organisms which are nonmotile -have cell walls bulit of chitin -have no chlorophyll -reproduce by means of spores The spores are produced either sexually or asexually. Most fungi are saprophytes, that is, they live on decaying organic matter and play main role in the degradation of organic matter (containing carbon and nitrogen). Without this kind of microorganisms we can drown in our own wastes. A few fungi, however, can cause significant plant and animal diseases. Of the more than 250 000 fungal species, only about 150 are know to cause human infections. Characteristic features of fungi: emerged 800 million years ago eukaryotic, heterotrophic organisms (saprophytes, parasites, symbionts) presence of: nuclei, mitochondria, Golgi apparatus, reserve substances (glycogen, fats). cosmopolitan (air, water, soil, skin, plant wastes, etc.) Characteristic features of fungi: they develop in aerobic and relatively anaerobic conditions (yeasts) most of them are mesophiles (25-30C), but they can develop at temperatures from -12C to + 68C the limit value of water content in the substrate for their growth is 11- 14% the optimal development at pH 5-6 (the tolerance range of some species is pH 1-10) development in the substrate with> 10% osmotic pressure light does not matter for their growth, they may only show phototropism (e.g. Mucor, Rhizopus), however, stimulates or inhibits the production of mycotoxins (e.g. aflatoxin B1)  Characteristic features: -morphology *yeast- single - cells *molds- mycelium (mycelium) single or multicellular, made of hyphae) A - multicellular B - single –cell C - budding yeast cells  Characteristic features: -cellular wall composed mainly of polysaccharides: β-glucans, cellulose, aminopolysaccharides -chitin, chitosan, as well as proteins and lipids structurally connected with glucan and chitin Fig. Structure of the cell wall of Neurospora sp. 1-outer layer (β-glucan) 2-glycoprotein lattice linked to protein and β-glucan 3-layer of proteins 4-chitin in the protein layer Pigments are located in the cell wall (the color of the mycelium from colorless to black, antigens and many enzymes (related to its synthesis, lysis, decomposition and enzymes responsible for the degradation of the substrate components).  Characteristic features: two types of mold mycelium: air nutrient Typical microbiome of polish soil Penicillium, Aspergillus, Trichoderma, Rhizopus, Mucor, Beauveria, Gliocladium, Humicola, Acremonium, Myrothecium, Paecilomyces, Ttrichothecium, Fusarium, Alternaria, Rhizoctonia, Botrytis etc.  Glomeromycota - mycorrhizal fungi - they create arbuscular mycorrhiza (fungal cells penetrate the cortical cells of plant roots) with many species of herbaceous plants and trees, fungi - symbiotes, - no sexual reproduction, - asexual reproduction by thick walled chlamydospores, e.g. the genus Glomus  Zygomycota Rhizopus sp. They are cosmpolitan genus of some 10 species of filamentous fungi in the family Rhizopodaceae Saprophytic and pathogenic fungi (R. stolonifer and R. arrhizus) Many members of Rhizopus are commonly used in industrial processes R. oryzae is useful for the production: *lactic acid *for alcoholic fermentation *the biosorption of heavy metals *R. delemar produces fumaric acid and biotin *enzymes – chitinase, lipase *surfactants  Rhizopus sp. Asexual reproduction Sexual Sexual reproduction phases: -plasmogamy - two protoplasts fuse together to form a dikaryon (pair of nuclei) -karyogamy - joining two haploid nuclei into a diploid nucleus - zygote -meiosis - reduction division restoring the haploid number of chromosomes  Ascomycota - molds Penicillium sp., Aspregillus sp. They are cosmpolitan genus of some 200 species of filamentous fungi. It is wide spread and has a wide range of habitats. saprophytic and pathogenic fungi some species are known to produce antibiotics (penicillin) and toxic compounds (mycotoxins) Use in biotechnology *production of antibiotics *production of cheeses *production of citric acid *biodegradation of organochlorine compounds *enzymes production *zinc removal from sewage  Trichoderma sp. Ascomycota the genus Trichoderma are soilborne, green-spored Benefits : - popular in nature - the ability to settle very diverse environments - they grow quickly in artificial cultures and produce conidial spores profusely - naturally resistant to many toxic compounds - production of a wide range of enzymes (cellulase, hemicellulase, xylanase, pectinase, β-1,3-glucanase, chitinase and protease) - production of antimicrobial substances (harzianic acid, tricholine, heptelidic acid, viridine, peptaibols, glyovirin, massoilacton, gliotoxins, alamethicin, 6-pentyl-a-pyrol, glisoprenin).  The estimation of interaction between microorganisms- Inoculate the medium with Trichoderma sp. and Penicillium sp. ‚0’-no inhibition ‚8’- total inhibition  Reproduction of molds belong to Ascomycota Asexual Sexual  Yeasts belonging to Ascomycota - single-cell, with round shapes - cell wall made of hemicellulose  Saccharomyces cerevisiae (yeast) fermentation process (ethanol production) backing dietary supplements due to the high content of B vitamins, proteins, amino acids and mineral compounds - zinc, phosphorus, magnesium, selenium, chromium yeast is a model organism in molecular biology of eukaryotes (23% of the yeast genome is the same compare to the human genome) production of medicines, including hirudin (anticoagulant proteins), insulin and hepatitis B vaccines S. cerevisiae is currently an ideal model for studying human neurodegenerative diseases probiotic supplement in the treatment of Clostridium difficile colitis addition to various cosmetics  Ascomycota – Saccharomyces cerevisiae (yeast) Asexual reproduction budding yeast Bud (daughter cell) Mother cell Schizosaccharomyces transverse cell division  Sexual reproduction Saccharomyces cerevisiae (yeast) Ascospore is a spore produce inside an ascus. ascus In ascus is created 4 ascospores. Sexual reproduction: ascospore - fusing haploid vegetative cells - karyogamy - meiosis - formation of 4 ascospores Sexually predominantly under unfavorable conditions by the formation of the ascus with ascospores (up to 4 pieces), Anamorphic fungi - a very numerous group of fungi characterized only by asexual reproduction (reproduction by the formation of chlamydospores or conidial spores), - their common feature is septated mycelium, - saprophytes, plant parasites, species pathogenic to humans and animals, - 3 classes: Hyphomycetes Agnomycetes Coelomycetes - Representatives of the class Hyphomycetes - Fusarium, Alternaria, Geotrichum genus  Anamorphic fungi Geotrichum candidum - It is the member of the human microflora - sparophytic has been isolated from soil, fruits and vegetables - use to production of cheeses such as CAMAMBERT - lipase production - agent of the human disease geotrichosis  Geotrichum candidum arthrospores  Anamorphic fungi Fusarium sp. It is genus widely distributed in soil and associated with plants saprophytic fungi and plant pathogenic some species are known to produce toxic compounds (mycotoxins)  Fusarium sp. macroconidia  Meaning of fungi 1. Production of secondary metabolites: - antibiotics - organic acids - enzymes 2. Production of blue cheeses 3. Production of ethyl alcohol 4. Bakery 5. Production of animal feed (yeast) 6. Mineralization of organic matter in the soil, and thus take part in the formation of humus 7.Symbiotic organisms: - mycorrhiza -digestive system of some animals. 8. In addition to saprophytic species of fungi, there are parasitic species that develop on human or animal skin, textiles, food and plants (mycoses, spoilage of milk, silage, fruit, vegetables, bread, etc.). Candida albicans Fusarium