2. The objective
• Discuss the difference between
Eukaryotic and prokaryotic organisms.
• Differentiate between different groups
of fungi.
• Microscopic examination of unicellular,
multicelluar fungi and actinomycetes.
3. • FUNGI are eukaryotic organisms (is
any organism whose cells contain
a nucleus and other structures (organelles)
enclosed within membrane).
5. • The study of Fungi is termed Mycology.
• The Diseases caused by fungi are called Mycotic
diseases or mycosis.
• In general , fungi are beneficial, while some fungi can
cause damage.
6. Yeasts
• Unicellular oval or spherical fungi.
• Increased in number asexually by a process termed
budding
7. • Yeast are facultative anaerobes : Respire
aerobically if oxygen is present, but is capable of
switching to fermentation or anaerobic respiration if
oxygen is absent.
8. • The vast majority of yeasts are nonpathogenic and
some have a great value in industrial fermentaion
such as Saccharomyces Sp. are used for both baking
and brewing.
• Because of their unicellular and microscopic nature,
yeast colonies appear similar to bacterial colonies on
solid media.
• The yeast Candida is normal flora of the
gastrointestinal tract and is also found on the skin
and on the mucous membrane of the mouth and
vagina.
9. • Candida may become an Opportunistic pathogen
(those that take advantage of certain situations).
• The most common Candida sp. Causing human
infections is C. albicans ( 50-60% ) C. glabrata is
second (15-20%) C. parapsilosis ( 10-20%)
10. Actinomycetes:
• Actinomycetes are a specific group as bacteria.
Morphologically they resemble fungi because of their
elongated cells that branch into filaments or
hyphae.
• During the process of composting mainly
thermophilic (adapted to high temperatures) and
thermotolerant actinomycetes are responsible for
decomposition of the organic matter at elevated
temperatures. In the initial phase of composting the
intensive increase of microbial activity leads to a self
heating of the organic material. High temperatures in
composting help to kill viruses, pathogenic bacteria.
11. Actinomycetes:
• Actinomycetes live predominantly aerobically, i.e.
they need oxygen for their metabolism. The compost
material should therefore be well aerated.
• Generally, actinomycetes grow on fresh substrates
more slowly than other bacteria and fungi. During
the composting process the actinomycetes degrade
natural substances such as chitin or cellulose.
• Natural habitats of thermophilic actinomycetes are
silos, corn mills, air conditioning systems.
• actinomycetes are found to be responsible for
allergic symptoms in the respiratory tract (e.g.
"extrinsic allergic alveolitis", EAA).
