Transcript Introduction to the Fungi

Fungi
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)
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)
What else do fungi “eat?”
• Predatory fungi, catch
and digest other
organisms (like
nematodes)
But still absorptive nutrition! Just have to catch it first…
Some are parasites
Athlete’s foot
Ringworm
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.
• Lichens are a combination fungus and
alga.
• Commensal relationship
Lichens
What does
a fungus
body look
like?
Fungi are made of hyphae
(cells joined in thread-like strands)
Mushrooms are for sexual reproduction
(~flowers)
Mycelium = body of the fungus
Hyphae = the “bricks” from which the mushroom is built
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
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
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)
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)
Mycorrhizal benefits
Fungi increase the
water and nutrients
available to their plant
partners leading to:
•Greater plant
productivity
Left: No mycorrhizal fungi
Right: With mycorrhizal fungi
Fungi are important decomposers!
Fungi decompose
cellulose to glucose and
play a major role in the global
carbon cycle.
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
Why do fungi make antibiotics?
Fungi produce
antibiotics for the
same reason we
need them:
to fight off
bacterial
infections