The Fungus Among Us The strange and fascinating world of our most visible decomposers.

The Fungus Among Us

The strange and fascinating world of our most visible decomposers

What we WON’T do:

• Learn to identify edible mushrooms

• Freak out because there are approximately 10,000 fungal spores in each cubic meter of air

• Panic because we have Pneumocystis carinii living in our lungs right now (yes, YOUR lungs)

What we WILL do:

• Learn about unique reproduction strategies

• Appreciate that fungi are essential for life on this planet

• Delight in all the ways that fungi make our lives richer

Characteristics of Fungi

• Eukaryotic heterotrophs– digestion is external

• Chitin in cell walls– same chemical as found in insect exoskeletons

• Dikaryotic stage (some)– cells fuse (plasmogamy) but nuclei don’t!– therefore cells are n+n instead of 2n

Terminology• -gamy = marriage or fusion

• -karyon = nucleus -plasm = gel inside cell

• -ploid = sets of chromosomes (1n, 2n)

• spore = 1n cell that can germinate into a fully functional 1n cell

myco = fungus

Functions• saprobes (decomposers)

– up to armpits in dead bodies without them– nutrient cycles come to a halt (carbon, nitrogen,

etc.)

• parasites/pathogens– you name it, including other fungi

• mutualists– you name it– especially important: plants (~ 90% of all plants

MUST have fungal associations)

Ectomycorrhizae vs. Arbuscular mycorrhizae

Unicellular fungi = yeast

Multicellular: functional unit = hypha

mushroom = fruiting body

ONLY fungi with motile cells

Chytrids

http://frogmatters.wordpress.com/2008/03/

http://www.environment.nsw.gov.au/animals/FrogChytridFungus.htm

Chytrid infection of frogs has caused extinction of several species across the world.

Ease of global travel has exacerbated the problem.

Glomeromycota: ONLY reproduce asexually, NONE are unicellular

EXTREMELY important function: arbuscular mycorrhizae

from: http://www.google.com/imgres?imgurl=http://www.nature.com/ncomms/journal/v1/n4/images_article/ncomms1046-f4.jpg&imgrefurl=http://www.nature.com/ncomms/journal/v1/n4/full/ncomms1046.html&usg=__7YegfK1Kf9F35TIwzcySA-_ewp0=&h=411&w=600&sz=80&hl=en&start=21&sig2=8ks-42yCpXd5mTIoNyp4YA&zoom=1&tbnid=eVz-gQfOr2MucM:&tbnh=112&tbnw=163&ei=pending&prev=/images%3Fq%3Dglomerulomycete%26hl%3Den%26biw%3D1276%26bih%3D558%26gbv%3D2%26tbs%3Disch:10%2C503&itbs=1&iact=hc&vpx=829&vpy=179&dur=2964&hovh=186&hovw=271&tx=129&ty=120&oei=2E6WTPvYIc6dnwel0MyeBw&esq=2&page=2&ndsp=22&ved=1t:429,r:12,s:21&biw=1276&bih=558

Glomeromycota

http://life8eiml.sinauer.com/Animations/Chapter30/Animation-30-01.swf

WEIRD!

aka Cup Fungi

Saccharomyces cerevisiae favorite ‘cup’ fungus = Brewer’s & Baker’s yeast!!

Penicilium varieties responsible for Roquefort cheese and antibiotics!

http://americanmushrooms.com/coolest.htm

Mushroom Structure

http://www.google.com/imgres?imgurl=http://fungalguide.landcareresearch.co.nz/Images/MushroomDiagram.jpg&imgrefurl=http://fungalguide.landcareresearch.co.nz/WebForms/FG_About.aspx&usg=__MPTyhWk_-4gq6NXoTEPNv879uFo=&h=490&w=500&sz=50&hl=en&start=0&sig2=LQ_ilJDUBLdMLQWzxs_WHA&zoom=1&tbnid=JVlyrP5HGZ2xLM:&tbnh=132&tbnw=135&ei=dl-WTJi1HIe2nAelxeWlBw&prev=/images%3Fq%3Dmushroom%2Bstructure%26hl%3Den%26biw%3D1276%26bih%3D558%26gbv%3D2%26tbs%3Disch:1&itbs=1&iact=hc&vpx=1006&vpy=60&dur=187&hovh=222&hovw=227&tx=133&ty=132&oei=dl-WTJi1HIe2nAelxeWlBw&esq=1&page=1&ndsp=18&ved=1t:429,r:5,s:0

3 feet in length, ~20 lbs!http://news.bbc.co.uk/2/hi/uk_news/scotland/3839363.stm http://www.youtube.com/watch?v=EF65xGRNfwo

http://healthyhomegardening.com/Most_Viewed_Pages.php?m1=12

http://www.youtube.com/watch?v=GScyw3ammmk

http://www.youtube.com/watch?v=e1E48_W0DS4

http://www.youtube.com/watch?v=q7Qem8OloIY&feature=related

Common smut (Ustilago maydis) on an ear of corn.

Deuteromycete Pneumocystis carinii in human sputum.

Penicillium sp. growing on agar.