Why Study?
Kingdom Fungi
Are microorganisms
Can cause human disease
(directly or by toxins)
Can affect plants we eat
Wheat rust is a fungus
The famous potato famine in
Ireland was caused by a fungus
(Almost instantly destroyed the primary food source
(Unicellular)
Are Useful
for the majority of the population. Approximately one
million people died during the 5 years of the famine.)
(Multicellular)
Mycology = Study of Fungus
Metabolic activities, particularly yeasts, are
used in many industrial fermentation
processes (beer, wine, cheese, bread)
Used in other products – Citric acid in Coke is
produced by Aspergillus
Used to produce Antibiotics and other drugs
Penicillium
Streptomycium
Cephalosporin
Cyclosporin
Mycosis = A fungal disease
DIFFERENCES BETWEEN FUNGI AND BACTERIA
CHARACTERISTIC
BACTERIA
FUNGI
Cell Wall
Peptidoglycan
Chitin
Classification
Prokaryotes
(“pre-nucleus” or
no nucleus)
Eukaryotes
(true nuclei)
Exoenzyme
Yes
Yes
Acidic conditions
Variable growth
Grows well
Moisture
Variable
Tolerate less moisture
(although like humidity)
Motility
Variable
Non motile
# of cells
Unicellular
Unicellular/Multicellular
Nutrition
Some bacteria can
make own food
Heterotrophs/chemoheterotrophs
(Obtain nutrients by adsorbing dissolved
organic material through cell wall and
plasma membrane)
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CHARACTERISTIC
BACTERIA
Grow in a wide variety of
environmental conditions
FUNGI
Organelles
No
Yes – Specialized structures
with specific functions
Osmotic Pressure
Variable
Tolerate higher osmotic
pressure (sugar, salt)
Oxygen Requirements
Aerobic &
Anaerobic
Molds – Aerobic
Yeast - Facultative anaerobe
Primary identification
Metabolism &
Morphology
Morphology
Reproduction
Asexual
(Binary fission)
Asexual (mitotic)
Sexual (Meiotic)
Size
Smaller
Larger
Spores
Survival
Reproduction
Structural Complexity
Less Complex
More Complex
Temperature
Mostly mesophiles
Tolerate wide range
Decomposition of organic matter
Recycle nutrients
Capable of ingesting complex carbohydrates
such as lignin (composed of wood) that
bacteria cannot use for nutrients
Can grow on walls, shoe leather, & old
newspaper, etc
Yeasts
Function
Soil
Water
Fruits
Jelly
Refrigerator
Humidity
Dry climate
Yeasts
Non-filamentous
Unicellular
Widely distributed in
nature
Frequently found on
fruits, leaves, and bark
as a white, powdery
coating
Yeasts – asexual reproduction
Widely used in the food industry
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Yeasts – Sexual reproduction by spore formation
Yeasts
Pseudohypha – occurs when buds fail to
detach themselves resulting in a short chain
Budding Yeast
Pseudohypha
Candida albicans
Common pathogenic yeast
Candidiasis refers to a Candida infection
Features & Descriptive Terms Used to
Classify fungus and fungal growth
Moniliasis – another name for Candidiasis
Morphology
Mucocutaneous candidiasis
Monilial intertrigo
Thallus – Macroscopic
mold colony
Mycelia – Mass of
strands forming
the thallus
Dimorphism
Oral candidiasis = thrush
Hypha – Strand of a mycelia
(Hypha = singular / Hyphae = pleural)
Thallus
Mycelium
Haustorium
Hyphal Organization
Sexual Spores
Asexual Spores
Haustorium - A rootlike attachment in
parasitic plants including fungi that
penetrates and obtains food from the host
Vegetative Hyphae – grows in or on surface of
growth medium
Reproductive Hyphae / Aerial Hyphae –
Originates from vegetative hyphae and produce
spores
Septate Hyphae – Hyphal strand composed of
individual cells by a crosswalk or septum
Coenocytic Hyphae (non septate) – Mass of
cytoplasm with multiple nuclei
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Type of hyphae
Septate – Hyphal strand composed of
individual cells by a crosswalk or
septum
Coenocytic (Non-septate) –
Hypha lack septum. Composed of
a mass of cytoplasm with multiple
nuclei
Reproductive or aerial hyphae
Vegetative Hyphae
Oospores
The mold you see on bread is reproductive
hyphae with spores. Actually have mold
before you see it (vegetative hyphae)
Septate Hyphae
Sexual Spores
Ascospores
Asexual spores
Basidiospores
Zygospores
Sporangiospores
Conidiospores
Chlamydiospores
Zoospores
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Dimorphism – difference in structure
among the same species
Fungal dimorphism refers to the ability of some
fungi to exhibit different characteristics when
grown at different temperatures
Example; Histoplasma capsulatum
Is a Unicellular yeast at 370C
Is a filamentous mold/hypha at 250C
4 major fungal phyla
Ascomycota
Omycota
Basidiomycota
Zygomycota
Zygomycota
Conjugation Fungi/Produce Zygospores
Zygomycota
Ascomycota
Sac Fungi/Produce Ascospores
“Conjugation Fungi”
Saprophytic Molds
Coenocytic hypha
Zygospores (sexual
spore formation)
Sporangiospores
(asexual spore
formation)
Examples
Rhizopus
Mucor
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Ascomycota
“Sac Fungi”
Septate Hyphae
Ascospores = Sexual spore
formation
Conidiospores = Asexual
spore formation
Examples
Alternaria
Aspergillus
Fusarium
Penicillium
Sordaria
Basidiomyocta
Club fungi/produce basidiospores
Basidiomycota
Oomycota
Water molds/produce oospores
& motile zoospores
“Fleshy Fungi”
“Club Fungi”
Mushrooms
Septate hyphae
Basidiospores = Sexual spore
formation
Fragmentation = Asexual
spore formation
Examples
Coprinus
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Oomycota
“Water Molds”
Aquatic habitat
Coenocytic hyphae
Oogonia with oospores
= sexual spore
formation
Zoospores = asexual
spore formation
(motile/have flagella)
Examples
Saprolegnia
Non Classified - Physarium polycephalium
Also known as “slime mold”
Feeds by phagocytosis /
and “cytoplasmic streaming”
Has properties like an amoeba
CLASSIFICATION
(Named by sexual reproduction)
Phylum
Example
Location or
Description
Ascomycota
(Molds & some
yeasts =
Saccharomyces
)
Alternaria
Aspergillus
Fusarium
Penicillium
Sordaria
“Sac Fungi”
Bacidiomycota
(Macroscopic
species)
Coprinus
Oomycota
Zygomycota
SPORES
Hyphal
Organization
Sexual spore
Formation
Asexual
spore
formation
Septate
Ascospores
Produced in a sac
or ascus called a
perithecium
Conidiospores –
Budding –
identical to
parents
“Fleshy Fungi”
“Club fungi”
(Mushrooms)
Septate
Bacidiospores
produced in club
shaped cap called
basidium
Fragmentation
Saprolegnia
Aquatic habitats
“Water Molds”
Coenocytic
Formed by fusion
of 2 hyphae =
oogonia with
oospores inside
Zoospores
(Motile / have
flagella)
Mucor
Rhizopus
Saphrophytic
Molds
“Conjugation
Fungi”
Coenocytic
Zygospores
formed by fusion
of 2 hyphae with
mixing of DNA
Sporangiospores
Formed in a
sporangium
(spore sac)
which is on the
end of a
sporangiophore)
Observation Techniques
PLATE GROWTH (of Penicillium notatum)
WET MOUNT (of Saccharomyces cerrevisiae)
AGAR BLOCK/Slide culture
SPORE PRINT (of a gill fungus)
half amoeba/half mold
Media used to isolate yeast and other fungi
Differences between molds & bacteria on
agar plates
Sabouraud agar – simple nutrients
of glucose and peptone and a low
pH which inhibits the growth of most
other organisms
Potato Dextrose Agar – PDA
Malt Extract Agar - MEA
Mold on an agar plate
Bacteria on an agar plate
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Saccharomyces cerevisiae – on agar
Microscopic Saccharomyces cerevisiae
Yeast used in making bread, wine, beer
Microscopic Fusarium
Microscopic Mucor
Microscopic Sordaria
Microscopic Aspergillus
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Microscopic Penicillium
Microscopic Rhizopus
Microscopic Alternaria
What’s the largest thing in the world?
Compounds used in treating superficial
and systemic fungal infections
Superficial = at or near surface
Nystatin, Miconazole
It's..... a fungus!
Scientific name Armillaria ostoyae
Located in the Malheur National
Forest in eastern Oregon.
Carpets nearly 10 square kilometers
(an area equivalent to about 1,600 football fields).
Lives in soil and spreads mainly along tree roots by
shoestring-like threads called rhizomorphs
Only surface evidence are its fruiting bodies, known
commonly as honey mushrooms.
Up to 8,500 years old
Causes large production losses due to root disease
Systemic Mycosis - Histoplasmosis
Systemic – deep seated infections
Ketoconazole, Itraconazole
Histoplasma capsulatum – A Dimorphic fungus
Amphotericin B (fungazone)
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Systemic mycosis - Coccidioidomycosis
Coccidioides immitis – also called San Joaquin Valley Fever
Systemic mycosis - Blastomycosis
Systemic mycosis - Aspergillosis
Aspergillus spp – similar infections are also caused by Rhizopus & Mucor
Systemic mycosis - pneumocystis
Pneumocystis carnii
Blastomyces dermatitidis
Pneumocystis carnii pneumonia is the 2nd most common opportunistic
infection of AIDS patients (Most common = tuberculosis)
originating as a respiratory infection, and usually spreading to the lungs, bones, and skin.
Superficial subcutaneous mycosis –
typically results from fungus entering
tissue via a wound.
Sporotrichosis – Sporothrix schenckii
Superficial subcutaneous mycosis
Candidiasis – Candida albicans
More oral thrush
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Superficial Cutaneous Mycosis
Caused by dermatophytes (dermatomycosis)
Stachybotrys
Tinea capitis or
Tinea unguim or
Tinea pedis or
“Ringworm of scalp”
“Nail infection”
“Athlete’s Foot”
Tinea cruris or
“Jock Itch”
Tinea corpora or
Tinea barbae or
“Ringworm of the body”
“Barber’s Itch”
Diseases/Conditions associated with the
mycotoxins
A culture of Stachybotrys chartarum on PDA
Diagnosis
Ergot Poisoning –
Has toxic spores that cause a multitude of
symptoms including cognitive impairment and
pulmonary hemorrhage
Can grow in walls of homes
Produces hallucinations and gangrene;
associated with infected rye
Aflatoxin –
Carcinogen associated with peanuts and grains;
Produced by Aspergillus flavus
Wood Lamp (UV) causes superficial fungal infections to fluoresce
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