morphology of fungi
TRANSCRIPT
![Page 1: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/1.jpg)
Morphology of fungi
![Page 2: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/2.jpg)
Introduction• Mykes (Greek word) : Mushroom• Fungi are eukaryotic protista; differ from bacteria and
other prokaryotes.1. Cell walls containing chitin (rigidity & support), mannan & other
polysaccharides 2. Cytoplasmic membrane contains ergosterols3. Possess true nuclei with nuclear membrane & paired chromosomes4. Cytoplasmic contents include mitochondria and endoplasmic
reticulum5. Divide asexually, sexually or by both6. Unicellular or multicellular7. Most fungi are obligate or facultative aerobes
![Page 3: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/3.jpg)
![Page 4: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/4.jpg)
Difference from Bacteria• Cell wall consists of chitin not peptidoglycan like bacteria
• Thus fungi are resistant to antibiotics as penicillins
• Chitin is a polysaccharide composed of long chain of n-acetylglucosamine.
• Also the fungal cell wall contain other polysaccharide, β-glucan, which is the site of action of some antifungal drugs.
• Cell membrane consist of ergosterol rather than cholesterol like bacterial cell membrane
• Ergosterol is the site of action of antifungal drugs, amphotericin B & azole group
![Page 5: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/5.jpg)
Downloded from www.pharmacy123.blogfa.com
![Page 6: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/6.jpg)
![Page 7: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/7.jpg)
Fungal Morphology Molds Yeasts
Many pathogenic fungi are dimorphic, forming hyphae at ambient temperatures but yeasts at body temperature.
05/02/2023 Dr.T.V.Rao MD 7
![Page 8: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/8.jpg)
Structure of Fungus
• Yeast :- Unicellular budding yeast
• Hypha :- Elongation of apical cell produces a tubular, thread like structure called hypha. Hyphae may be septate or nonseptate.
• Mycelium :- Tangled mass of hyphae is called mycelium. Fungi producing mycelia are called molds or filamentous fungi.
![Page 9: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/9.jpg)
Mycelium• Mass of branching intertwined hyphae
a. Vegetative Mycelium- hyphae that penetrate the supporting medium and absorb nutrients
b. Aerial Mycelium- hyphae projects above the surface of medium and bearr the reproductive structure called conidia.
![Page 10: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/10.jpg)
Vegetative types
• Favic chandeliers
• Nodular organs
• Racquet hyphae
• Spiral hyphae
![Page 11: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/11.jpg)
Classification of fungi
1.Morphological classification
2.Systematic classification
![Page 12: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/12.jpg)
1. Yeasts
2. Yeast-like fungi
3. Filamentous fungi (molds)
4. Dimorphic fungi
Morphological classification
![Page 13: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/13.jpg)
Yeasts These occur in the form of round or oval bodies
which reproduce by an asexual process called budding in which the cell develops a protuberance which enlarges and eventually separates from the parent cell.
Yeasts colonies resemble bacterial colonies in appearance and in consistency
Examples are- Saccharomyces cerevisiae, Cryptococcus neoformans
![Page 14: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/14.jpg)
Yeast form
![Page 15: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/15.jpg)
Yeast colonies
Mucoid colonies
![Page 16: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/16.jpg)
Cryptococcus neoformans
Downloded from www.pharmacy123.blogfa.com
![Page 17: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/17.jpg)
Yeast-LikeYeast like fungi grow partly as yeast and partly as
elongated cells resembling hyphae. The latter form a pseudomycelium.
Example: Candida albicanspseudomycelium
![Page 18: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/18.jpg)
Molds or Filamentous Fungi The basic morphological elements of filamentous fungi
are long branching filaments or hyphae, which intertwine to produce a mass of filaments or mycelium
Colonies are strongly adherent to the medium and unlike most bacterial colonies cannot be emulsified in water
The surface of these colonies may be velvety, powdery, or may show a cottony aerial mycelium.
Reproduce by the formation of different types of spores
Example: Dermatophytes, Aspergillus, Penicillium, Mucor, Rhizopus
![Page 19: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/19.jpg)
mycelium: septate mycelium: non septate
![Page 20: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/20.jpg)
Downloded from www.pharmacy123.blogfa.com
![Page 21: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/21.jpg)
Colony Morphology
![Page 22: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/22.jpg)
Dimorphic FungiThese are fungi which exhibit a yeast form in the
host tissue and in vitro at 370C on enriched media and mycelial form in vitro at 250C
Examples:Histoplasma capsulatumBlastomyces dermatitidisCoccidioides immitisParacoccidoides brasiliesisPenicillium marneffeiSporothrix schenckii
![Page 23: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/23.jpg)
Histoplasma capsulatum - Dimorphism
• Filamentous mold in environment– Thin septate hyphae, microconidia, and tuberculate
macroconidia (8-14 µm)• Budding yeast (2-4 µm) in tissue
– Dimorphic transition is thermally dependent and reversible (25°C 37°C).
Hyphae, micro- and macroconidia Yeast within histiocyte
![Page 24: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/24.jpg)
Systematic classification
• Based on sexual spores formation: 4 classes
1. Zygomycetes 2. Ascomycetes reproduce sexually3. Basidiomycetes4. Deuteromycetes (fungi imperfectii)
![Page 25: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/25.jpg)
Zygomycetes • Lower fungi• Broad, nonseptate hyphae• Asexual spores -
Sporangiospores: present within a swollen sac- like structure called Sporangium
• Examples: Rhizopus, Absidia, Mucor
![Page 26: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/26.jpg)
Ascomycetes
• Sexual spores called ascospores are present within a sac like structure called Ascus.
• Each ascus has 4 to 8 ascospores
• Includes both yeasts and filamentous fungi
![Page 27: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/27.jpg)
Ascomycetes• Narrow, septate hyphae• Asexual spores are called conidia borne on
conidiophore• Examples: Penicillium, Aspergillus
![Page 28: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/28.jpg)
BasidiomycetesSexual fusion results in the formation of a club shaped organ called base or basidium which bearspores called basidiospores
Examples: Cryptococcus neoformans, mushrooms
![Page 29: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/29.jpg)
Deuteromycetesor Fungi imperfectii
• Group of fungi whose sexual phases are not identified
• Grow as molds as well as yeasts• Most fungi of medical importance belong to
this class• Examples: Coccidioides immitis,
Paracoccidioides brasiliensis, Candida albicans
![Page 30: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/30.jpg)
Reproduction and sporulation
Types of fungal spores
1.Sexual spores
2.Asexual spores
![Page 31: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/31.jpg)
Sexual spores• Sexual spore is formed by fusion of cells and
meiosis as in all forms of higher life• Ascospores
– Ascus– Ascocarp
• Basidiospores
• Zygospores
![Page 32: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/32.jpg)
Asexual spores
These spores are produced by mitosis
1. Vegetative spores
2. Aerial spores
![Page 33: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/33.jpg)
Vegetative spores • Blastospores: These are formed by budding from
parent cell, as in yeasts
• Arthrospores – formed by segmentation & condensation of hyphae
• Chlamydospores – thick walled resting spores developed by rounding up and thickening of hyphal segments.
![Page 34: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/34.jpg)
Aerial spores
1. Conidiospores Spores borne externally on sides or tips of hyphae are called conidiospores or simply conidia
2. Microconidia- conidia are small and single
3. Macroconidia- conidia are large
4. Sporangiospores- spores formsWithin the sporangiophores.
![Page 35: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/35.jpg)
• Microconidia - Small, single celled
• Macroconidia – Large and septate and are often multicellular
![Page 36: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/36.jpg)
Pictures of fungi on LPCB mount
Aspergillus Penicillium
![Page 37: Morphology of fungi](https://reader036.vdocument.in/reader036/viewer/2022062503/58cee8a81a28ab333d8b57e3/html5/thumbnails/37.jpg)