|MYCOVIRO

2nd SEMESTER
A.Y. 2022 – 2023

MYCOLOGY AND VIROLOGY – LECTURE

Mycologists are persons or these are scientists who

INTRODUCTION TO MYCOLOGY 
study fungi.
 Mycotoxicology it's the study of fungal toxins and
Categories of Microbes their effects to the body.
 Mycosis is the study of the diseases cause by fungi.
 Cellular
Distinguishing Characteristics of Fungi
 Acellular
1. Eukaryotic and non-vascular
2. Don’t have chlorophyll, non-motile
3. Cell wall is made up of chitin
4. Obligate aerobes and grow best a a neutral pH
5. Needs moist environment which are necessary
for their growth
 fungi contains spores so that spores that they have
can withstand even dry environment and they also
reproduce by means of their spores and that spores
ADDITIONAL / PROF’S NOTES we call it condia

One of the main differentiating points of eukaryotic cells Fungi are Eukaryotic
and prokaryotic cells is that the eukaryotic cells they • With true nucleus enclosed by nuclear membrane
have two nucleus which is enclosed in a membrane so • May produce energy
that is where we can find their genetic material however •Prokaryotes don’t have true nucleus and
for prokaryotes they don't have true nucleus so they the nuclear membrane
nucleus there is what we call as the nucleoid. • Nucleoid – nucleus of prokaryotes

Archaeons these are microorganisms that can live in an Fungi don’t have chlorophyll
extreme environment like for example the thermophils. • Not capable of synthesizing own food
Thermophils they are microorganisms that can live or can - store their food as glycogen whereas the plants they
tolerate very high temperature so by the name itself store their food as starch
“Thermo” means they can tolerate extreme temperatures.
The cell wall of fungi is made of CHITIN
Halo Fields are microorganisms that can tolerate high
•Chitin
salt concentration or meaning to say they can live in an
– responsible for very rigid cell wall of
environment wherein there is high salt concentration and
Fungi
for archaeans we also have methanogens so they can
- means it gives shape to the fungi how about for the
use methane like as a source of their energy for their
plant cell wall. The plant cell wall is made up of cellulose.
growth and for their differentiation

“MYCOLOGY”
o Study of fungi
o Greek : “mykos” = mushroom

Fungi is present in the environment as subprobes so

they are saprophytic. So what do I mean by that one so
Saprobes meaning to say they rely on decaying matter
like decaying vegetation and plants for sources of
nitrogen

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 Heterotrophic meaning to say they are organisms

that eat other plants or animals for energy and
nutrient.
 Chemoautotrophic - these are organisms that obtain
their energy from chemical reaction but their source
of carbon is the most oxidized form of carbon which
is the carbon dioxide.
 Autotrophic microorganisms are also called as
photosynthetic organisms of like the green plant or
cyanobacterium so they can utilize energy from light
to synthesize organic molecules
A.Nucleus
B.Bud diving daughter cell coming from parent cell
FUNGI EXIST IN TWO FORMS C.Yeast
D.Nucleus of the Yeast

YEAST
• Single vegetative cell (unicellular)
• Typically produces smooth, creamy colonies
• Morphologic appearance of all yeast are somewhat
similar
• Identification is based on the result of biochemical
testing
• They reproduce by budding

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TYPES OF MYCELIUM

1. Vegetative – are those that penetrates the surface of

the medium and absorbs nutrients.
2. Aerial – are those that grow above the agar surface
3. Fertile – are aerial hyphae that bear reproductive
structures such as conidia or sporangia.

2 TYPES OF HYPHAE
Septate Aseptate
– contains septa/crosswalls - no septa/crosswalls

MOLDS

•Fuzzy / wooly appearance which is due to mycelium

- Mycelium is the collection of long strands of root-like
structures called hyphae

HYPHAE
 is the functional unit of fungi TYPES OF HYPHAE BASED ON PIGMENTATION
 thread-like chains of cells that form thefriuting body
and mycelium • Hyaline – don't possess any pigment in their cell
Mycelium - Underground network of hyphae that have wall (transparent)
grouped together •Phaeoid or dematiaceous – fungi that possess
Fruiting body - reproductive structure of a fungus and melanin pigments in their cell wall (pigmented)
grows above the ground • Colonies are grey, black or olive.
•Ex. Bipolaris, Cladosporium, Exophiala

FORMS OF VEGETATIVE HYPHAE

• Antler hyphae – irregular pattern

• Racket hyphae – club-like shape
• Spiral hyphae – tight coils all throughout
• Rhizoid hyphae – root-like; most common;
penetrate below the culture medium

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Dimorphism
• With 2 morphologic
states:
• Yeast at 37oC
• Molds at RT

 Spiral Hyphae- spirally coiled and they are

commonly seen or commonly observed in
Tricophyton mentagrophyes
 Pectinate body - these are short unilateral Example of Dimorphic Fungi
projections from the hyphaethat resemble a broken 1.Blastomyces dermatitidis- live in moist soil composing
comb . Commonly seen in Microscoporum audouinii. organic matter.People can be infected with blastomyces
 Favic chandelier- these are the group of hyphae tips dermatitis by inhaling the mold that produces pores
that collectively resemble a chandelier or the antlers 2.Coccidioides immitis - called as the valley fever ; live in soil
of the deer. Occur in Trichophyton schoenleinii. 3.Histoplasma capsulatum - inhalation of organisms from
 Nodular nodular hyphae- or nodular organ is an soil but they are mostly associated with bird or bad bat
enlargement of the mycelium that that consists of droppings
closely twisted hyphae. Observed in Microsporum 4.Sporothrix schenckii- also known as Rose Gardener's
canis or often times also in Trichophyton disease. This affects the cutaneous area of the skin also it
mentagrophytes. can affect the lungs
 Rocket Hyphae - regular enlargement of one end of
each segment with the opposing and remaining thin .
We can observe them in Epidermophyton flocosum
also Trichophyton mentagrophytes.
 Rhizoid Hyphae - root-like structures seen in
portions of vegetative hyphae and in some members
of zygomycytes

Reproduction of Fungi
Asexual Reproduction
•Primary basis of their identification
•Production of conidia following mitosis
•Conidiogenous cells

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Phialoconidia or Conidia are formed from conidiogenous Sexual Reproduction

cells. The phialide it's a vase-like structure that blows out •Involves 2 homogenous hyphae and these
the conidia. Conidia are product of asexual reproduction hyphae must be identical in nature
Annelide is a ring-like structure. •Joining of 2 nuclei from compatible matching
strains followed by meiosis

At the end there is the production of zygospores which is

the product of sexual reproduction. Two identical Hyphae
fusing together then two nuclei fusingtogether forming
zygospore.
Arthroconidia is another form of asexual reproduction.
It is formed by fragmentation of fertile Hyphae. These are
propagules which are formed by segmentation of existing
hyphae

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IMPORTANT / PROF’S NOTES

ADDITIONAL / PROF’S NOTES

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