Study of general characteristics, morphology, physiology, cultivation, classification and reproduction of fungi

1. Dr. Pulipati Sowjanya
Professor
Vignan Pharmacy College
Guntur
Presented By

2. S.No Cell Features Fungi Bacteria
1. Cell Type Eukaryotic Prokaryotic
2. Cell Membrane Sterols present Sterols absent except in Mycoplasma
3. Cell Wall
Glucans, mannans, chitin (no
peptidoglycan)
Peptidoglycan
4. Spores
Sexual and Asexual
reproductivespores
Endospores(not for reproduction);
some asexual reproductive spores
5. Metabolism
Limited to heterotropic;
aerobic, facultatively anaerobic
Heterophic, autotrophic; aerobic,
facultatively anaerobic, anaerobic
Comparison of Selected Features of Fungi and Bacteria

3. CHARACTERISTIC FEATURES OF FUNGI
1. Study of fungi is known as Mycology
2. Fungi are Eukaryotic organism
3. Morphology:
Fungi exists in two fundamental forms, filamentous or hyphal
form (MOLD) and singe celled or budding form (YEAST).
But for the classification of fungi, they are studied as mold,
yeast, yeast like fungi and dimorphic fungi.
Yeast is Unicellular while Mold is multicellular and filamentous

4. CHARACTERISTIC FEATURES OF FUNGI
4. Fungi lacks Chloroplast.
5. Mode of nutrition:
Fungi are organotropic heterotrophs.
Mostly Fungi are saprophytic and some are Parasitic
6. Fungi grow best in acidic environment ( tolerate acidic pH).
7. Fungi can tolerate high sugar concentration and dry condition
8. Most of the fungi are Obligate aerobes (molds) and few are facultative
anaerobes (yeasts)

5. 9. Optimum temperature of growth for most saprophytic fungi is
20-30° C while (30-37°C) for parasitic fungi.
10. Growth rate of fungi is slower than that of bacteria.
11. Cell wall is composed of chitin
12. Cell membrane consists of ergosterol
CHARACTERISTIC FEATURES OF FUNGI

6. 13. Reproduction: Both asexual and sexual mode of reproduction
Asexual methods: fragmentation, somatic budding, fission, asexual
spore formation
Sexual methods: gametic copulation, gamete-gametangium
copulation, gametangial copulation, somatic copulation and
Spermatization.
CHARACTERISTIC FEATURES OF FUNGI

7. • According to morphological features the fungi are grouped as
• Yeasts
• Yeast like fungi
• Moulds
• Dimorphic fungi
MORPHOLOGY OF FUNGI

8. Yeasts:
• They are unicellular organisms
• Round or oval in shape
• Divide by budding
• On culture media, they produce creamy mucoid
colonies
• Ex: Cryptococcus neoformans
Yeast-like Fungus:
• These fungi grow partly as yeasts and partly as chains
of elongated budding cells known as pseudohyphae.
• On culture media, they produce creamy colonies.
• Ex: Candida albicans
MORPHOLOGY OF FUNGI

9. Moulds:
• They grow as branching filaments about 2-10 mm in width.
• These filaments are known as hyphae, which may be septate or
non-septate.
• The hyphae grow and branch to form tangled mass of growth
known as mycelium.
• Aerial mycelium – grows on surface of the culture medium
• Vegetative mycelium – grows within the medium
• Moulds reproduce by forming different types of sexual and
asexual spores.
• Ex: Dermatophytes, Aspergillus, Rhizopus
MORPHOLOGY OF FUNGI

10. Dimorphic Fungi:
•Exhibit different morphologies at different temperatures.
•Grows as yeast forms at 37°C, whereas at 25°C they grow as filamentous form.
•Ex: Pathogenic fungi
MORPHOLOGY OF FUNGI

11. Fungi exhibit 4 main cellular structures
capsule, cell wall, cytoplasmic membrane & cytosols
Capsule:
• Fungi is an extracellular polysaccharide layer surrounding the fungal cell.
• It is responsible for virulence of the organism.
• Elicits host immune response.
• Presence of capsule is a diagnostic criteria for some diseases.
STRUCTURE OF FUNGI

12. Cell Wall:
• It is rigid and multilayered.
• Contains chitin, mannans, polysaccharides and
polypeptides.
• Many fungal antigens are prepared from the cell
wall material.
• It contains some adhesive molecules that take
part in the attachment and invasion of the
organisms.
STRUCTURE OF FUNGI
Figure: Fungi Cell Wall Structure

13. Cytoplasmic Membrane:
• The membrane lies next to the cell
wall and enclosing the cytosols.
• It is made up of glycoproteins,
ergosterols and lipids.
• Ergosterol in the fungal cytoplasmic
membrane is the site of attack of
many antifungal agents.
STRUCTURE OF FUNGI
Figure: Fungi Cytoplasmic Membrane Structure

14. Cytosols:
• Fungal cells possess complex structures
called cytosols in the cytoplasm.
• Since fungi are eukaryotic, these structures
include nucleus with nuclear membrane,
ribosomes, mitochondria, golgi apparatus,
endoplasmic reticulum, microvesicles
STRUCTURE OF FUNGI
Figure: Fungi Cell Structure

15. • Fungi withstand to extreme environment. Ex: Yeasts & Molds
• Grow in high sugar concentration which inhibits bacterial growth.
• Jams & jellies are spoiled by fungi but not by bacteria.
• Fungi tolerate more acidic conditions than other microbes.
• Molds & yeasts are aerobic but some yeasts are facultative anaerobic.
• Fungi can grow at temperature between 22-30°C with optimum temperature 28°C.
• Pathogenic species grow at 30-37°C.
• Some fungi grow at 0°C that spoils meat & vegetables stored in refrigerator.
PHYSIOLOGY OF FUNGI

16. • Fungi are heterotropic – cannot use CO2 as carbon source but use organic
compounds as source of carbon.
• Some species use inorganic nitrogen, nitrates, nitrites or ammonium salts.
• Most fungi use organic nitrogen, hence fungi media contains peptone.
PHYSIOLOGY OF FUNGI

17. • Fungi – molds & yeasts can grow aerobically on bacteriological culture media
• Grow at temperature ranging from 20-30°C.
• Grow well in acidic PH media 5.6.
• Grow at high concentration of sugar.
• Sabouraud derived fungi media containing maltose and peptone
• Examples of fungi media
• Potato dextrose agar media
• Sabouraud’s glucose agar media
CULTIVATION OF FUNGI

18. CLASSIFICATION OF FUNGI

19. Fungi reproduce by – Asexual reproduction
Sexual reproduction
Asexual reproduction: It is also known as somatic (or) vegetative reproduction. It
doesn’t involve the union of nuclei, se cells or sex organs. It is accomplished by
i. Fission of somatic cells yielding two similar daughter cells.
ii. Budding of somatic cells or spores
iii. Fragmentation or disjointing of the hyphal cells, each fragment becomes a
new organism.
iv. Spore formation
a. Sporangiospores b. Conidiospores c. Oidia (or) Arthrospores
d. Chlamydiospores e. Blastospores
REPRODUCTION OF FUNGI

20. a. Sporangiospores: Single celled spores are formed
within sporangia at the end of hyphae
Aplanospores - non-motile sporangiospores
Zoospores – motile sporangiospores
b. Conidiospores:
Single – celled conidia are called microconidia
Large multi-celled conidia are called macroconidia
c. Oidia (or) Arthrospores: Single – celled spores
formed by disjointing of hyphal cells.
d.Chlamydiospores: Thick walled, single celled
spores formed by disjointing of hyphal cells
e. Blastospores: These are spores formed by budding
REPRODUCTION OF FUNGI
Figure: Asexual spores

21. Sexual reproduction:
1. Gametic Copulation: Fusion of naked
gametes, one or both of which are motile
REPRODUCTION OF FUNGI
2. Gamete - Gametangial Copulation:
Two gametangia come into contact but
do not fuse; the male nucleus migrates
through a pore or fertilization tube into
the female gametangium.

22. Sexual reproduction:
3. Gametangial Copulation: Two gametangia
or their protoplasts fuse and give rise to a
zygote that develops into a resting spore.
REPRODUCTION OF FUNGI
4. Somatic Copulation: Fusion of somatic
or vegetative cells.
5. Spermatization: Union of a special
male structure called spermatium with a
female receptive structure.

23. SEXUAL SPORES OF FUNGI
Ascospores: These are single celled spores
produced in a sac called an ascus. Usually
there are 8 ascospores in each ascus.
Zygospores: Thick walled spores formed
when the two sexually compatible
hyphae or gametangia fuse together.

24. SEXUAL SPORES OF FUNGI
Basidiospores: These are single
celled spores formed in a club-
shaped structure called basidium.
Oospores: These are formed within a
female structure known as oogonium

25. IMPORTANCE OF FUNGI
i. Important agents for biodegradation and bio-deterioration
ii. Use in industrial fermentation process.
Examples; Penicillium notatum is used for production of
penicillin antibiotics
Aspergillus niger is used for production of citric acid
Saccharomyces cerevisiae is used for alcohol production
iii. Used in bioremediation (reduces toxic concentration)
iv. Used in agriculture, horticulture and forestry, example;
biofertilizer and biopesticides

26. REFERENCES
Michael J. Pelczar, JR., E.C.S. Chan, Noel R. Krieg. Microbiology. 5th
edition. 333-350.
Prescott, Harley and Klein's, Microbiology. 5th edition. 553-564.