Downloded from www.pharmacy123.blogfa.com Fungi Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com What do fungi “eat?” Some fungi are decomposers. They break down complex molecules into simple ones. Examples: common bread mold (eats carbs in bread) shelf fungi on logs (eats carbs in cell wall of wood) white button mushrooms in store (eats sugars and cellulose in dung) Examples common bread mold (eats carbs in bread) shelf fungi on logs (eats carbs in cell wall of wood) white button mushrooms in store (eat carbs in dung - simple sugars or cellulose in cell walls ) Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com What do fungi “eat?” Some fungi are symbiotic fungi. They receive their food energy directly from a plant or algal partner Examples: mycorrhizal fungi (live on plant roots) lichens (contain algae) ADD TO DEFINITION OF FUNGI ON BOARD: 3. HETEROTROPHIC – CANNOT MAKE THEIR OWN FOOD - DECOMPOSE COMPLEX MOLECULES INTO SUGAR - RECEIVE SUGAR FROM SYMBIOTIC PARTNER MYCORRHIZAE (PARTNER WITH PLANT) LICHENS (PARTNER WITH ALGAE OR CYANOBACTERIA) 3. Downloded from www.pharmacy123.blogfa.com

What else do fungi “eat?” Predatory fungi, catch and digest other organisms (like nematodes) Fig. 10-20. The nematophagus fungus Arthrobotrys candida. Fig. 10-21. Formation of a net-like trap by  Arthrobotrys oligospora. Fig. 10-22. Arthrobotrys brocophaga developing constricting ring traps. ADD TO DEFINITION OF FUNGI ON BOARD: 3. HETEROTROPHIC – CANNOT MAKE THEIR OWN FOOD - DECOMPOSE COMPLEX MOLECULES INTO SUGAR - RECEIVE SUGAR FROM SYMBIOTIC PARTNER MYCORRHIZAE (PARTNER WITH PLANT) LICHENS (PARTNER WITH ALGAE OR CYANOBACTERIA) - PREDATORY – CATCH AND KILL OTHER ORGANISMS OR PARASITIC ON OTHER ORGANISMS But still absorptive nutrition! Just have to catch it first… Downloded from www.pharmacy123.blogfa.com

Some are parasites Athlete’s foot Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com Ringworm Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com How do fungi eat? Heterotrophs (cannot make their own food like plants) Secrete enzymes outside of their bodies, “digest” the food outside of their cells and then absorb the molecules into their cells. Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com Lichens are a combination fungus and alga. Commensal relationship Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com Lichens Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com What does a fungus body look like? Radial growth pattern Downloded from www.pharmacy123.blogfa.com

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Fungi are made of hyphae (cells joined in thread-like strands) MODULAR GROWTH - FRAGMENTATION = ASEXUAL REPRODUCTION!! Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com Mushrooms are for sexual reproduction (~flowers) Mycelium = body of the fungus Hyphae = the “bricks” from which the mushroom is built Downloded from www.pharmacy123.blogfa.com

Example of a “humungous fungus” Armillaria bulbosa – a mushroom producing wood decomposer Covers at least 38 acres in a forest in Michigan Estimated to weigh 100 tons (size of a blue whale) Estimated to be at least 1500 yrs old Draw how fungus is wood decomposer (white rot) with rhizomorphs Downloded from www.pharmacy123.blogfa.com

Why should you care about fungi? A few reasons: They make foods we like to eat Mycorrhizae are responsible for plant life on land and high productivity rates They decompose wood and organic matter Penicillin and other medicines Downloded from www.pharmacy123.blogfa.com

Examples of foods made possible by fungi Yeast Beer and Wine Bread Mushrooms White button, crimini,portabella Truffles, chanterelles Mycoprotein (food additive like tofu) Cheese Rennin, blue cheese Soy sauce Tempeh Citric acid (soft drinks) Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com Mycorrhizae “myco” = fungus and “rhiza” = root Symbiotic association between plant roots and fungi Several different types of association (defined by structure of fungus:plant interface) Types of mycorrhizae are defined by interface structures VAM - hyphae and arbuscules of an endomycorrhizal fungus in Asarum (wild ginger) (see Fig 15 in Brundrett & Kendrick 1988 Can. J. Bot. 66: 1153) Colonization of a root by an endomycorrhizal fungus. Note hyphae, arbuscules and vesicles. (Fig. 21 in Brundrett et al. 1985 Can. J. Bot. 63: 184-) ECTO - page 264 - dichotomous ectomycorrhizas (upper) and mycelial strands (lower) of Amanita muscaria on Pinus strobus.online Pictorial Supplement to The Fifth Kingdom - Chapter 17 Mycorrhizae - mutualistic plant-fungus symbioses. Photo posted by Bryce Kendrick and Mycologue Publications. Other acknowledgements Downloded from www.pharmacy123.blogfa.com

Downloded from www.pharmacy123.blogfa.com Mycorrhizal benefits Fungi increase the water and nutrients available to their plant partners leading to: Greater plant productivity (Lewis & Koide 1990, Stanley et al. 1993). Write on white board: Benefits to plant from mycorrhizal association 1. Increased plant nutrient supply by extending the volume of soil accessible to plants. 2. Increased plant nutrient supply by acquiring nutrient forms that would not normally be available to plants. 3. Increased drought tolerance. 4. Protection from parasitic fungi and nematodes. 5. Link plants together in physiological networks Root colonisation by ECM and VAM fungi can provide protection from parasitic fungi and nematodes (Duchesne et al. 1989, Grandmaison et al. 1993, Newsham et al. 1995, Little & Maun 1996, Cordier et al. 1998, Morin et al. 1999). Suppression of competing non-host plants, by mycorrhizal fungi has been observed (Allen et al. 1989). Significant amounts of carbon transfer through ECM fungus mycelia connecting different plant species has been measured (Simard et al. 1997). This could reduce competition between plants and contribute to the stability and diversity of ecosystems. Networks of hyphae supported by dominant trees may help seedlings become established or contribute to the growth of shaded understorey plants (Hogberg et al. 1999, Horton et al. 1999). Nutrient transfer from dead to living plants can occur (Eason et al. 1991). Left: No mycorrhizal fungi Right: With mycorrhizal fungi Downloded from www.pharmacy123.blogfa.com

Fungi are important decomposers! Fungi decompose cellulose to glucose and play a major role in the global carbon cycle. Fungi can break down lignin and cellulose (two most abundant organic molecules on earth) basiodiomycetes are only organisms that can break lignin down to CO2 lignin perioxidase breaks down lignin in “enzymatic combustion” removes electron from lignin molecule creating a free radical which leads to a series of uncontrolled and unpredictable reactions. Why have other organisms not evolved this ability? only save to do extracellularly. Very generalized enzyme (not specific) lignin highly variable molecule - combustion not used to harvest energy, purely to release cellulose from lignin matrix so can be digested. (Fungal “miners”) Downloded from www.pharmacy123.blogfa.com

Fungi make antibiotics - Penicillium WWI, bacterial infections killed more soldiers than bullets. 1928 Dr. Andrew Fleming working at St. Mary’s Hospital in London noticed that mold growing on staph bacterial culture plates had killed the pathogen zone of dead bacteria The action of penicillin is seen in Figure A. This shows an 'overlay plate', in which a central colony of the fungus Penicillium notatum was allowed to grow on agar for 5-6 days, then the plate was overlaid with a thin film of molten agar containing cells of the yellow bacterium, Micrococcus luteus. The production of penicillin by the fungus has created a zone of growth inhibition of the bacterium. This demonstration parallels what Alexander Fleming would have observed originally, although he saw inhibition and cellular lysis of the bacterium Staphylococcus aureus. Figure B shows the typical asexual sporing structures of a species of Penicillium. The spores are produced in chains from flask-shaped cells (phialides) which are found at the tips of a brush-like aerial structure. B&W is an actual photograph of Fleming’s dish (note clear lysed bacterial cells in zone around mold) Downloded from www.pharmacy123.blogfa.com

Why do fungi make antibiotics? Fungi produce antibiotics for the same reason we need them: to fight off bacterial infections Downloded from www.pharmacy123.blogfa.com