2. What do you mean by Microbiology?
Study of living organisms that
are not directly visible to naked
eye but only under the
microscope.
3. What is Medical Microbiology ?
Study that deals with causative agents of
infectious diseases, their pathogenesis,
diagnosis and treatment.
– Bacteriology
– Virology
– Parasitology
– Mycology
– Immunology
4. Bacteria
• Prokaryotes
• Single celled organism
• Ubiquitous in every habitat
• 10 times more bacteria in human
body than human cells.
• Few species are pathogenic and
cause infectious diseases.
8. Yeasts
• Unicellular
• Shape - round to oval
• Size – 3-4 um
• Reproduce asexually
by mitosis (Budding)
– Saccharomyces cerevisiae
– Candida albicans
9. Molds
• Fungi that grows in the form
of multicellular filaments
called hyphae
• Forms a mass of branching
intercalating hyphae known
as a mycelium.
– Penicillium notatum
– Rhizopus sps
– Mucor sps
– Aspergillus fumigatus
12. Prions
• An infectious agent composed
of protein in a misfolded form.
• Proteinaceous infectious
particles.
• PrPc PrPsc
• Affects the structure of
the brain and neural tissues
that are currently untreatable
and universally fatal
Diseases:
• Kuru
• Creuzfeldt-Jacob disease
13. Historical perspective
• Antony Van Leeuwenhoek
• Ducth merchant (1683)
• First to observe and
describe bacteria.
• “Animalcules”
14. Louis Pasteur (1822-1895)
• French chemist
• Father of modern microbiology
• Disproved theory of spontaneous generation
• Developed methods and techniques of
cultivation of microorganisms.
• Studies on pebrine (silkmworm disease),
anthrax, chicken cholera and hydrophobia.
• Attenuated Live vaccines.
15. Joseph Lister (1867)
• Professor of surgery
• Introduced antiseptic technique in
surgery
• Used Carbolic acid to kill bacteria
in wounds
• Father of antiseptic surgery
16. Robert Koch (1843-1910)
• German General practitioner
• Introduced methods for isolation of
pure strains of bacteria.
• Used agar as a setting agent in
culture media.
• Isolated anthrax bacilli in pure
culture.
• “Father of Medical microbiology”
• Koch’s postulates
17. Koch’s Postulates
• The organism must be regularly associated
with the disease and its characteristic lesions.
• The organism must be isolated from the
diseased host and grown in pure culture.
• The disease must be reproduced when a pure
culture of the organism is introduced into a
healthy, susceptible host.
• The same organism must be reisolated from
the experimentally infected host.
