1. Divisions of Fungi Basidiomycota Includes mushrooms
Called basidiomycetes
Basidiocarp
Dikaryotic stage (2 nuclei)
Basidiospores
Basidium

2. Divisions of Fungi: Life Cycle of Basidiomycota
Figure 8.7: The life cycle of a typical basidiomycete

3. Divisions of Fungi Basidiomycota About 25,000 named species
Puffballs
Shelf fungi
Earthstars
Stinkhorns
Jelly fungi
Gill fungi (including poisonous ones)
Rust disease
Smut disease

4. Divisions of Fungi Deuteromycota About 25,000 species
No currently identified form of sexual reproduction
Also known as deuteromycetes or Fungi Imperfecti
Conidia
Many human pathogens
Dermatophytes of athlete’s foot

5. Beneficial and Harmful Fungi
Yeasts
Saccharomyces
Ascomycota
Single cells
Saccharomyces cerevisiae
Baking
Accumulation of CO2 during Krebs cycle makes dough rise
Enzymes break down gluten, giving spongy texture
Saccharomyces ellipsoideus
Brewing
Fermentation results in production of CO2 and ethanol
Different starting materials give rise to wines and beers
Reproduced by permission of the National Research Council of Canada; E.M. Peterson, R.J. Hawlay, and R.A. Calerone. The Canadian Journal of Microbiology, 22(10):
Fig. 8.1a

6. Beneficial and Harmful Fungi
Lichens
Association between fungus and photosynthetic partner
Approximately 15,000 lichen species
Almost all have an ascomycetes as the fungus
Most frequent photosynthetic partners
Trebouxia (green algae)
Trentephila (green algae)
Nostoc (cyanobacterium)
© Popovici loan/ShutterStock, Inc.
Fig 8.10 lichens

7. Beneficial and Harmful Fungi
Lichens
Grow in a diversity of environments
Arid deserts
Arctic zones
Bare soil
Tree trunks
Rocky areas
Photosynthetic partner provides sugar and carbohydrates
Fungal partner supplies protection and basic biochemical building blocks
Can survive in as little as 2% water
Very slow growth (less than 10 mm per year)

8. Beneficial and Harmful Fungi
Mycorrhizae
Mutualistic fungi that live amongst roots of vascular plants
Over 5,000 species
Plant provides photosynthetic products
Fungi provide more nutrients than plant can absorb through roots alone
Garden plants typically associate with zygomycetes

9. Beneficial and Harmful Fungi
Fungi and human disease
Candida albicans
Normal vaginal flora
Held in check by other acid-producing flora
Overuse of antibiotics, which may kill normal flora, leads to yeast infection (candidiasis)
Can be treated
Antifungal creams
Eating yogurt
Normal oral flora
If immune depleted (e.g., AIDS), can infect mouth
Disease is called thrush
Treatment with oral antifungals
Reprinted with permission from the American Society for Microbiology (Balish, E., Balish, M.J., Salkowski, C.A., Lee, K.W., and Bartizal, K.F; Appli. Environ. Microbiol, 1984 May; 47(4): )
Figure 8.11: An SEM of Candida albicans

10. Beneficial and Harmful Fungi
Fungi and human disease
Cryptococcus neoformans
Infects lungs and meninges
Tinea diseases
Skin infections
Athlete’s foot
Barber’s itch
Jock itch
Ringworm
Reprinted with permission from the American Society for Microbiology (ASM News. December 1998, Vol. 64(12): ) Photo courtesy of Doctor Stuart Levitz, University of Massachusetts Medical Center.
Reprinted with permission from the American Society for Microbiology (Dykstra, M.A., Friedman, L. and Murphy, J.W.; Infect. Immun May; 16(1): )
Figure 8.13: Ringworm from Trichopyton tonsurans
Fig. 8.12: C. neoformans
© Medical-on-Line/Alamy Images

11. Beneficial and Harmful Fungi
Fungi and human disease
Aspergillus spp. (A. fumigatus, A. flavus, A. niger)
In large quantities or in the immunocompromised spores may infect the lungs causing Aspergillosis
Coccidioides immitis
Respiratory disease
American Southwest
May proceed to meningitis
Sometimes called Valley Fever
Histoplasma capsulatum
Found in bird droppings
Respiratory illness
Blastomyces dermititidis