MICROPARA LEC
CN2026
Elton Josh Cabrito | BSN 1F
Introduction to Microbiology
TOPIC OUTLINE
I.
Microbiology
i.
Virus
ii.
Bacteria
iii.
Protozoans
iv.
Fungi
v.
Multicellular Parasites
II.
III.
IV.
Importance of Microbiology
Classification of Microorganisms
Pioneers in Microbiology
Microbiology
- study of living microorganisms including viruses
- broad discipline includes:
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Bacteriology
Virology
Mycology
Parasitology
Components
• Colds
• Influenza
• Warts
• AIDS
• Mumps
• Rubella
• Measles
• Herpes
*Vaccines are available for protection to some viruses. *
Bacteria
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Prokaryotic; single celled (cytoplasm and nucleus)
Reproduce rapidly by diffusion (split into two)
Has four shapes:
o Cocci (round)
o Bacillus (elongated)
o Vibrio (comma shaped)
o Spiral (coiled/curved
▪ Spirilum – rigid bodies
▪ Spirochete – flexible bodies
Classification
a)
b)
c)
d)
Microbe
- terminology used for virus, bacteria, fungi (yeast/molds),
protozoa
VIRUS
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Smallest infectious agent (measured per nanometer)
Can’t be seen in microscope
Electron microscope is needed to view the microbe
Subcellular organisms
Have only nucleic acid surrounded by protein coat
Must live and grow in living cells of organisms
Two types: DNA and RNA
o RNA Virus Examples: Hepatitis B,
Hepatitis C, Covid-19, HIV
▪ Arrows if may processes e.g., heat
🡪 vasodilation
Illness Caused by Virus
Elton Josh Cabrito|BSN 1F
Shape
Ability to retain dyes
Ability to grow with or without air
Biochemical Reaction
Gram’s Stain
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Divide entirely into two groups: gram positive and
gram negative
o Crystal Violet Dye – positive
o Sapphire red – negative
Acid-Fast Stain Dye
– used to detect mycobacteria (e.g., tuberculosis)
Anaerobic
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Bacteria dies du to oxygen exposure
Aerobic
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Bacteria is immune to oxygen
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MICROPARA LEC
CN2026
Elton Josh Cabrito | BSN 1F
Special Bacteria
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Parasitic Insects
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Mycobacteria – with a mycolic acid cell wall
Rickettisiae – very small; mites and ticks usually carry
this
Chlamydiae – with cell wall and have an infectious
cycle.
Mycoplasmas – lack rigid cell wall
Bites and burrows into skin
Mosquito
Ticks
Mites
Lice
PROTOZOANS
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Single cell, eukaryotic, larger than bacteria
Found in soil and water
Examples: amoeba, flagellates, paramecium,
euglena, trypanosoma
Illness caused by Protozoans
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Malaria
Amoebic dysentery
Trichomoniasis vaginitis (flagellate)
FUNGI
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Eukaryotic, with rigid cell wall (chaitin)
Has two classifications:
o Yeasts – single celled, reproduce by budding
o Molds – multicelled, large, fuzzy, produce
spores.
Illness caused by Fungi
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Athlete’s foot
Ringworm
Thrush
Systemic infection
Meningitis – yeast from pigeon droppings
MULTICELLULAR PARASITES
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Importance of Microbiology
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Play a major role in recycling essential elements
Benefit society by food production, beverage,
antibiotic, and vitamins.
Curative agents of some important diseases.
New infectious diseases continue to emerge.
Microbiology impacts every facet of daily life.
Bioremediation
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Use microbes to remove toxins (oil spills)
Use microbes to control crop pests
Normal microbiota
Use other living organisms for nourishment
Parasitic Worms
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gy
Caused by poor sanitation
Tapeworm
Flatworm
Fluke
Roundworm
Elton Josh Cabrito|BSN 1F
Microbiology Branches
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Chemotherapy
Recombinant DNA Technology
Agricultural
Environmental
Medical and clinical
Genetic engineering
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MICROPARA LEC
CN2026
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Elton Josh Cabrito | BSN 1F
Paleomicrobiology
Sanitary
Veterinary
Biotechnology
Classification of Microorganisms
Taxonomy
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Organize, classify, and name living things.
Classify according to specific criteria
Each organism is placed into a classification
Founding father: Carl Von Linne
Classification – arrange bacteria into groups
Nomenclature – naming (binomial: genus & species)
Identification – practical use of classification criteria to
distinguish certain organisms. Matching characteristics of
“unknown” to list of known organisms.
PIONEERS IN MICROBIOLOGY
ANTON VAN LEEUWENHOEK (1632-1723)
Scientific Classifications (8)
a) Domain
b) Kingdom
c) Phylum
d) Class
e) Order
f) Family
g) Genus
h) Species
Mnemonic device: Dumb Kings Play Chess On Funny Green
Squares
Domain
Eubacteria – true bacteria, peptidoglycan (protein and sugar)
Archaea – odd bacteria, live in extreme
conditions/environments (e.g., high salt, heat)
Eukarya – have nucleus and organelles
Naming Microorganism
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Gives each microbe two names:
o Genus – noun, always capitalized
o Species – adjective, lowercase
Both underlined or italicized.
Elton Josh Cabrito|BSN 1F
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First person to see live bacteria and protozoa thus,
called “Father of Microbiology,” “Father of
Bacteriology,” and “Father of Protozoology.”
Created the first simple microscope/ single-lens
microscope.
Used “animalcules” to describe tiny living creatures.
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MICROPARA LEC
CN2026
Elton Josh Cabrito | BSN 1F
ROBERT KOCH (1843-1910)
LOUIS PASTEUR (1822-1895)
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Developed a rabies vaccine for humans in
serendipity.
Discovered that microorganisms cause fermentation
and disease.
Due to his process of pasteurization, he salvaged the
liquor and silk industries in France.
Developed vaccine against anthrax, chicken cholera,
and swine erysipelas.
Discovered that life could exist without oxygen.
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Proved that anthrax bacillus was the causative agent
of anthrax using the Koch’s Postulates.
Discovered that B. anthracis produces spores,
capable of resisting adverse conditions.
Developed methods of fixing, staining, and
photographing bacteria.
Developed methods on bacteria cultivation on solid
media.
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MICROPARA LEC
CN2026
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Discovered M. tuberculosis that causes tuberculosis
as well as Vibrio cholerae that causes cholera. (Both
bacteria)
His work on a protein derived from M.tuberculosis
produced skin test for diagnosis of tuberculosis.
Elton Josh Cabrito | BSN 1F
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Kosch’s Postulates
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mainly established to prove that a specific microbe is
the underlying cause of an infectious disease.
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1) A particular microbe must be found in all cases of
the disease and must not be present in healthy
animals or humans.
2) The microbe must be isolated from the diseased
animal or human and grown in pure culture in the
laboratory.
3) The same disease must be produced when microbes
from the pure culture are inoculated into healthy
susceptible laboratory animals.
4) The same microbe must be recovered from the
experi5) mentally infected animals and grown again in pure
culture.
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find a laboratory animal that can be infected with a
pathogen that causes human disease.
Some diseases, called synergestic infections or
polymicrobial infections, are caused not by one
particular microbe, but by the combined effects of
two or more different microbes. Examples of such
infections include acute necrotizing ulcerative
gingivitis (trench mouth) as well as bacterial
vaginosis. It is difficult to reproduce such infections
in the lab.
Another difficulty that is sometimes encountered while
attempting to fulfill Koch's Postulates is that certain
pathogens become altered when grown in vitro. Some
become less pathogenic, whereas others become
nonpathogenic. Thus, they will no longer infect animals
after being cultured on artificial media.
Not all diseases are caused by microbes. Many
diseases as rickets and scurvy, result from dietary
deficiencies. Some diseases are inherited because of
an abnormality in the chromosomes, as in sickle cell
anemia. Others, such as diabetes, result from
malfunction of a body organ or system. Still others,
such as cancer of the lungs and skin, are influenced
by environmental factors. However, all infectious
diseases are caused by microbes, as are 1. as all
microbial intoxications
Note: All infectious diseases and microbial
intoxications are by microbes.
Koch's Postulates not only helped to prove the
germ theory of disease but also gave a
tremendous boost to the development of
microbiology by stressing laboratory culture and
identification of microbes.
Exceptions to Kosch’s Postulates
- To fulfill Koch's Postulates, it is necessary to grow
the pathogen in the laboratory (in vitro) in or on
artificial culture media. However, certain pathogens
will not grow on artificial media (e.g., viruses,
rickettsias, chlamydias.)
- To fulfill Koch's Postulates, it is necessary to infect
laboratory animals with the pathogen being studied.
However, many pathogens are species-specific,
meaning that they infect only one species of animal.
For example, some pathogens that infect humans will
infect only humans. Thus, it is not always possible to
Elton Josh Cabrito|BSN 1F
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