2. Terminologies…
• Colony
– A visible mass of microbial cells arising from one cell or a
group of the same microbes.
• Procaryotes
– A cell whose genetic material is not enclosed in a nuclear
envelope
• Eucaryotes
– Cell having DNA inside a distinct membrane-enclosed nucleus.
LUDY MAE B. NALZARO, BSM, RN, MN 2
3. Terminologies…
• Algae
– Photosynthetic eukaryotes
• Bacteria
– Prokaryotic organism characterized by peptidoglycan cell wall
• Saprophytes/decomposers
– Organisms that obtain nutrients from dead organic matters
LUDY MAE B. NALZARO, BSM, RN, MN 3
4. What is Microbiology?
• Micro - too small to be seen with the naked eye
• Bio - life
• ology - study of
• Is the study of very small living organisms called
microorganisms/microbes.
• Microbes are ubiquitous
– Meaning they are virtually everywhere!
LUDY MAE B. NALZARO, BSM, RN, MN 4
6. • Microbes play important roles…
– They are living on/in our body
– Some colonize our body
– Produce oxygen thru photosynthesis
– Decomposition of dead organisms/waste
products of living organisms
• Decomposers/saprophyte
– Decompose industrial waste (oil spills) –
bioremediation
– Involved in Elemental cycle (carbon,
nitrogen,oxygen, sulfur and phosphorous
cycles)
LUDY MAE B. NALZARO, BSM, RN, MN 6
7. • Algae and bacteria serve as food for tiny
animals
• Aid in the digestion of food in human (E. coli)
• Microbes process our food and beverages –
biotechnology
• Genetic engineering
• Cause 2 categories of diseases:
– Infectious diseases (colonizes the body)
– Microbial intoxications (ingest toxin)
LUDY MAE B. NALZARO, BSM, RN, MN 7
8. Organisms included in the study
of Microbiology
• 1. Bacteria • Bacteriology
• 2. Protozoans • Protozoology
• 3. Algae • Phycology
• 4. Parasites • Parasitology
• 5. Yeasts and Molds
– Fungi • Mycology
• 6. Viruses • Virology
Microorganisms - Microbes - Germs
LUDY MAE B. NALZARO, BSM, RN, MN 8
9. 5 Kingdoms of Living Organisms
• 1. Animalia
• 2. Plantae
• 3. Fungi
• 4. Protista
• 5. Monera - Bacteria and Cyanobacteria
• Eukaryotic vs. Prokaryotic
LUDY MAE B. NALZARO, BSM, RN, MN 9
10. 5 Characteristics of Life
• 1. Cells
• 2. Maintain structure by taking up
chemicals and energy from the environment
• 3. Respond to stimuli in the external
environment
• 4. Reproduce and pass on their organization
to their offspring
• 5. Evolve and adapt to the environment
LUDY MAE B. NALZARO, BSM, RN, MN 10
11. Taxonomic Classification
• Man
• Kingdom • Animalia
• Division/Phylum • Chordata
• Class • Mammalia
• Order • Primate
• Family • Hominidae
• Genus • Homo
• species • sapien
LUDY MAE B. NALZARO, BSM, RN, MN 11
12. Taxonomic Classification
• Cat
• Kingdom • Animalia
• Phylum • Chordate
• Class • Mammalia
• Order • Carnivora
• Family • Felidae
• Genus • Felis
• species • domestica
LUDY MAE B. NALZARO, BSM, RN, MN 12
13. Binomial System of Taxonomic
Classification
• Use only the Genus and species
– Homo sapien
– Felis domestica
– Escherichia coli
• Genus and species are either underlined or
italicized
• Genus is always capitalized
• species is never capitalized
LUDY MAE B. NALZARO, BSM, RN, MN 13
14. Classification System
• 3 Domains 1978 Carl Woese
– 1. Bacteria
• Unicellular prokaryotes with cell wall containing
peptidoglycan
– 2. Archaea
• Unicellular prokaryotes with no peptodoglycan in
cell wall
– 3. Eukarya
• Protista
• Fungi
• Plantae
• Animalia
LUDY MAE B. NALZARO, BSM, RN, MN 14
15. Bacteria - what comes to mind?
• Diseases
• Infections
• Epidemics
• Food Spoilage
• Only 3% of all known bacteria cause human
diseases
• About 4% of all known bacteria cause plant
diseases
• 95% of known bacteria are non-pathogens
LUDY MAE B. NALZARO, BSM, RN, MN 15
16. Microbes Benefit Humans
• 1.Bacteria are primary decomposers -
recycle nutrients back into the environment
(sewage treatment plants)
• 2. Microbes produce various food products
– cheese, pickles, green olives
– yogurt, soy sauce, vinegar, bread
– Beer, Wine, Alcohol
LUDY MAE B. NALZARO, BSM, RN, MN 16
17. 3. Microbes are used to produce Antibiotics
• Penicillin
• Mold
– Penicillium notatum
• 1928 Alexander Fleming
LUDY MAE B. NALZARO, BSM, RN, MN 17
18. 4. Bacteria synthesize chemicals that our
body needs, but cannot synthesize
• Example: E. coli
– B vitamins - for metabolism
– Vitamin K - blood clotting
• Escherichia coli
– Dr. Escherich
– Colon (intestine)
LUDY MAE B. NALZARO, BSM, RN, MN 18
19. 5. Biochemistry and Metabolism
• Very simple structure
• rapid rate of reproduction
• provides “instant” data
LUDY MAE B. NALZARO, BSM, RN, MN 19
20. 6. Microbial Antagonism
• Our normal microbial flora prevents
potential pathogens from gaining access to
our body
LUDY MAE B. NALZARO, BSM, RN, MN 20
21. 7. Insect Pest Control
• Using bacteria to control the growth of
insects
• Bacillus thuringiensis
– caterpillars
– bollworms
– corn borers
LUDY MAE B. NALZARO, BSM, RN, MN 21
22. 8. Bioremediation
• Using microbes to clean up pollutants and
toxic wastes
• Exxon Valdez - 1989
• 2 Genera
– Pseudomonas sp.
– Bacillus sp.
LUDY MAE B. NALZARO, BSM, RN, MN 22
23. 9. Recombinant DNA Technology
Gene Therapy Genetic Engineering
• Bacteria can be manipulated to produce
enzymes and proteins they normally would
not produce
– Insulin
– Human Growth Hormone
– Interferon
LUDY MAE B. NALZARO, BSM, RN, MN 23
24. 10. Microbes form the basis of
the food chain
Marine and fresh water microorganisms
LUDY MAE B. NALZARO, BSM, RN, MN 24
25. Microbes do benefit us, but they are also
capable of causing many diseases
• Pneumonia Whooping Cough
• Botulism Typhoid Fever Measles
• Cholera Scarlet Fever Mumps
• Syphilis Gonorrhea Herpes 1
• Chlamydia Tuberculosis Herpes 2
• Meningitis Tetanus RMSV
• Strep Throat Lyme Disease AIDS
• Black Plague Diarrhea Gangrene
LUDY MAE B. NALZARO, BSM, RN, MN 25
26. History of the Study of
Microorganisms
• 1665 Robert Hooke
– “little boxes” - “cells”
– Cell Theory - all living things are made up of
cells
LUDY MAE B. NALZARO, BSM, RN, MN 26
27. Spontaneous Generation
• Theory that life just “spontaneously”
developed from non-living matter
• Example:
– toads, snakes and mice - moist soil
– flies and maggots - manure and decaying flesh
LUDY MAE B. NALZARO, BSM, RN, MN 27
28. Experiments to disprove
Spontaneous Generation
• Francesco Redi 1668
– Showed that worms which appeared on rotting meat
were from fly eggs
• Rudolph Virchow 1858
– Theory of Biogenesis
• Cells can only arise from preexisting cells
• Louis Pasteur 1861
– Showed that appearance of microbes in sterilized media
was from air-borne bacteria
– Showed that sterilized materials remained sterile if kept
isolated from the external environment
LUDY MAE B. NALZARO, BSM, RN, MN 28
29. Anton van Leeuwenhoek 1674
- 1st person to actually see living microorganisms
“wee animalcules”
LUDY MAE B. NALZARO, BSM, RN, MN 29
30. ANTON VAN LEEUWENHOEK
• 1st to see live bacteria and protozoa
• FATHER OF MICROBIOLOGY
• FATHER OF BACTERIOLOGY & PROTOZOOLOGY
• Fabric merchant, a surveyor, wine assayer and a minor city
official
• Hobby:
– ground tiny glass lenses, which he mounted in small
metal frames (single-lens microscope)
LUDY MAE B. NALZARO, BSM, RN, MN 30
31. ANTON VAN LEEUWENHOEK
• He never speculated on the
origin of microbes nor associate
them with infectious disease.
LUDY MAE B. NALZARO, BSM, RN, MN 31
33. • Scientist became convinced of the existence of tiny creature (not
seen by naked eye)
• SPONTANEOUS GENERATION THEORY /ABIOGENESIS was
established
– Life could develop spontaneously from inanimate
substances/nonliving organisms.
– UNTIL the time of Louis Pasteur and John Tyndall who
disproved the theory and prove that
• “LIFE CAN ONLY ARISE FROM
PREEXISTING LIFE ALONE”
LUDY MAE B. NALZARO, BSM, RN, MN 33
34. LOUIS PASTEUR
• Contributions makes the
foundation of
– science of microbiology
– modern medicine…
LUDY MAE B. NALZARO, BSM, RN, MN 34
35. LOUIS PASTEUR’S CONTRIBUTION…
• 1. Wine contamination: Discovered
what occurs during alcoholic
fermentation.
– Demonstrated that different microbes
produce different fermentation
products.
– E.x. yeast converts glucose in grapes
to ethanol by fermentation
– Acetobacter, a contaminating
bacteriaconverts glucose to acetic
acid (vinegar)- ruining the taste of the
wine.
LUDY MAE B. NALZARO, BSM, RN, MN 35
36. 2. Thru experiment, dealth the fatal blow to
the theory of spontaneous generation.
LUDY MAE B. NALZARO, BSM, RN, MN 36
37. Pasteur designed special “swan-necked flasks”
with a boiled meat infusion
Shape of flask allowed air in (vital force) but trapped
dust particles which may contain microbes
LUDY MAE B. NALZARO, BSM, RN, MN 37
39. LOUIS PASTEUR’S CONTRIBUTION …
• 3. Discovered forms of life that are with
no oxygen.
– Aerobes – microbes needs Oxygen
– Anaerobes – microbes can live without
oxygen
LUDY MAE B. NALZARO, BSM, RN, MN 39
40. LOUIS PASTEUR’S CONTRIBUTION…
4. Pasteurization – process that kills microbes
that cause wine to spoil
- Can be used to kill pathogens in liquids.
- Process:
- Heating and maintaining to
63-65oC for 30 minutes or
73-75oC for 15mins
- Note: not ALL microbes are killed,
ONLY the pathogens
LUDY MAE B. NALZARO, BSM, RN, MN 40
41. LOUIS PASTEUR’S CONTRIBUTION…
• 5. Discovered the causative agent that
were causing silkworm diseases in silk
industry in France and how to prevent
such disease.
• 6. Contributed on the GERM THEORY
OF DISEASE – specific microbes cause
specific infectious diseases.
– e.x. anthrax caused by Bacillus anthracis
– TB by Mycobacterium tuberculosis
LUDY MAE B. NALZARO, BSM, RN, MN 41
42. LOUIS PASTEUR’S CONTRIBUTION…
7. Championed changes in hospital
practices to minimize the spread of
disease by pathogens.
8. Developed vaccines to prevent
cholera,anthrax and swine
erysipelas (skin disease)
9. Developed RABIES vaccine in dogs
and successfully used to treat
human rabies.
LUDY MAE B. NALZARO, BSM, RN, MN 42
43. Germ Theory of Disease
• Hard for people to believe that diseases were
caused by tiny invisible “wee animalcules”
• Diseases, they thought, were caused by:
– demons
– witchcraft
– bad luck
– the wrath of God
– curses
– evil spirits
LUDY MAE B. NALZARO, BSM, RN, MN 43
44. Robert Koch - 1st to prove that
bacteria actually caused diseases
• 1876
• Microbial Etiology of Infectious Disease
– etiology - the cause of a disease
• Developed methods of fixing, staining, and
photographing bacteria
• Established “scientific rules” to show a cause and
effect relationship between a microbe and a
disease
– Koch’s Postulates
LUDY MAE B. NALZARO, BSM, RN, MN 44
45. Staining Koch Postulate
LUDY MAE B. NALZARO, BSM, RN, MN 45
46. Koch’s Postulates
• 1. The same organisms must be found in all
cases of a given disease.
• 2. The organism must be isolated and
grown in pure culture.
• 3. The isolated organism must reproduce
the same disease when inoculated into a
healthy susceptible animal.
• 4. The original organism must again be
isolated from the experimentally infected
animal.
LUDY MAE B. NALZARO, BSM, RN, MN 46
47. Exceptions to Koch’s Postulates
1. Some organisms have never been grown in
pure culture on artificial media
Treponema pallidum - Syphilis
LUDY MAE B. NALZARO, BSM, RN, MN 47
48. Exceptions to Koch’s Postulates
Mycobacterium leprae
Leprosy
Never been grown in pure culture on artificial media
Seven Banded Armadillo
LUDY MAE B. NALZARO, BSM, RN, MN 48
49. Exceptions to Koch’s Postulates
• In exclusively human diseases, it is not
morally acceptable to inoculate a deadly
pathogen into a “human guinea pig”
• HIV
LUDY MAE B. NALZARO, BSM, RN, MN 49
50. Koch established the Microbial Etiology
of 3 important diseases of his day
• 1. Cholera (fecal-oral disease)
– Vibrio cholerae
• 2. Tuberculosis (pulmonary infection)
– Mycobacterium tuberculosis
– Work on tuberculin (protein from M. tuberculosis) that led to dev’t of
skin testing to diagnose TB.
• 3. Anthrax (sheep and cattle)
– Bacillus anthracis
– Discovered that B. anthracis produce spores that is capable of resisting
adverse conditions.
LUDY MAE B. NALZARO, BSM, RN, MN 50
51. Anthrax
• Bacillus anthracis
– Gram (+), non-motile, aerobic, spore forming rod
– Streptobacilli with central spores
– Livestock
• Sheep, cattle, goats
– Humans
• Handle hides, wool, goat hair, handicrafts from the Middle
East made from animal products
LUDY MAE B. NALZARO, BSM, RN, MN 51
52. 3 Forms of Human Anthrax
• 1. Cutaneous Anthrax
– Enters thru cut or
abrasion
– Results in painless
ulcer (1-3 cm) with
black (necrotic) center
– About 20% mortality
rate in untreated cases
LUDY MAE B. NALZARO, BSM, RN, MN 52
53. • 2. Gastrointestinal Anthrax
– Contaminated meat
– Abdominal pain, fever,
vomiting blood, severe
diarrhea
– 25% to 60% mortality rate
LUDY MAE B. NALZARO, BSM, RN, MN 53
54. • 3. Inhalation Anthrax
• Initial symptoms
resemble common
cold
– Progress to severe
breathing problems
and shock
– Usually results in death
1-2 days after onset of
acute symptoms
– Mortality rate 99% in
untreated cases
– Treatment usually not
effective after
symptoms are present
LUDY MAE B. NALZARO, BSM, RN, MN 54
55. Anthrax as a Biological Weapon
• Deadly if not treated early
• Spores can be produced in large quantities using basic
knowledge of biology
• Spores may remain viable for years (60 at least)
• Spores can be spread
– Missiles, rockets, bombs, mail, crop dusters ?
• No cloud or color
• No smell
• No taste
• Antibiotics – only effective if administered early (within
24 –48 hours)
LUDY MAE B. NALZARO, BSM, RN, MN 55
56. Koch - 1st to use Agar to solidify
culture media
LUDY MAE B. NALZARO, BSM, RN, MN 56
57. Golden Age of Microbiology 1857 - 1914
• Pasteur
– Pasteurization
– Fermentation
• Joseph Lister
– Phenol to treat surgical wounds – 1st attempt to control infections
caused by microoganisms
• Robert Koch
– Koch’s Postulates
• Edward Jenner
– vaccination
• Paul Erlich
– 1st synthetic drug used to treat infections
– Salvarsan - arsenic based chemical to treat Syphilis
• “salvation” from Syphilis
LUDY MAE B. NALZARO, BSM, RN, MN 57
58. Naming of Bacteria
• Genus and species - Binomial System of
Taxonomic Classification
• Information usually given:
– 1. Describes an organism
– 2. Identifies a habitat
– 3. Honors a scientist or researcher
LUDY MAE B. NALZARO, BSM, RN, MN 58
62. Microbiology: A Human Perspective
• Microorganisms cannot be seen without the aid of a
microscope
• There are more than 200,000 known microbes
• Exist in virtually any environment that has water
• Exhibit tremendous biodiversity
• Compose the largest biomass group of living
organisms
• Microbes exist for more than 3.5 billion years
LUDY MAE B. NALZARO, BSM, RN, MN 62
63. Applications of Microbiology
• Food production: bread, beer
• Bioremediation: decontamination
of hazardous wastes
• Useful products: ethanol fuel,
antibiotics, amino acids
• Genetic engineering:
pharmaceuticals, vaccines
• Genomics: genome sequencing
permits understanding of disease
mechanisms
LUDY MAE B. NALZARO, BSM, RN, MN 63
64. Medical microbiology
• Infectious diseases have killed
more people than all wars and
natural disasters combined
• Outbreaks have changed the
course of history
• Vaccines have dramatically
decreased the incidence of
infectious diseases, especially
in children
LUDY MAE B. NALZARO, BSM, RN, MN 64
65. Medical microbiology (cont.)
• Re-emergence of “Old” Infectious
Diseases
– Cases of whooping cough have increased
in the last few years
– Many microbes have evolved antibiotic
resistance
LUDY MAE B. NALZARO, BSM, RN, MN 65
66. Medical microbiology (cont.)
• Emerging infectious diseases
– As humans encroach upon wild habitat, new infectious agents (microbes) are
discovered
– These agents are typically hosted by animals and are termed zoonotic agents
Agent Host Disease
Ebola virus Bats Ebola hemorrhagic fever
SARS virus Bats Severe acute respiratory syndrome
Sin Nombre virus Deer mouse Hantavirus cardiopulmonary syndrome
Nipah virus Bats Nipah encephalitis
Dengue virus Mosquitos Dengue fever; Dengue hemorrhagic fever
Machupo virus Vesper mouse Bolivian hemorrhagic fever
Avian influenza viruses Various birds Influenza
Some recently discovered agents and their animal hosts
LUDY MAE B. NALZARO, BSM, RN, MN 66
67. Terminologies…
• Bacteriocins
– Toxins produce by enterobacteria that are lethal to
related strains of bacteria.
• Resident flora
– Collective vegetation in a given area in one part of
the body, yet produce infection in another.
• Infection
– Is an invasion of body tissue by microbes and their
growth
LUDY MAE B. NALZARO, BSM, RN, MN 67
68. • Infectious agent
– Microbes that cause infection.
• Asymptomatic/subclinical
– Microbes do not produce clinical evidence of
disease.
• Disease
– Detectable alteration in normal tissue function
LUDY MAE B. NALZARO, BSM, RN, MN 68
69. • Virulence
– Microbe’s ability to produce disease
• Communicable disease
– Infectious agents that can be transmitted to an individual by direct
or indirect contact or as airborne infection
– e.x. common colds
• Pathogenicity
– Ability to produce disease
• Pathogen
– Disease causing microbes
– 3% of known microbes are capable of causing disease.
• Non-pathogens
– Do not cause disease.
LUDY MAE B. NALZARO, BSM, RN, MN 69
70. Terminologies…
• Opportunistic pathogen
– Causes disease only in a susceptible individual
• Asepsis
– Freedom from disease-causing microbes.
• Medical asepsis
– All practices intended to confine a specific
microbes to a specific area, limiting the #, growth,
& transmission of microbes.
LUDY MAE B. NALZARO, BSM, RN, MN 70
71. • Medical asepsis
– Objects are CLEAN (absence of almost all microbes)
• Surgical asepsis/sterile technique
– Practices that keep an area or object free of all
microbes
– Practices that destroys all microbes & spores
• Sepsis
– State of infection and can take many forms, including
septic shock.
LUDY MAE B. NALZARO, BSM, RN, MN 71
73. Microorganisms are said to be
ubiquitous.
Can you think of any locations that
would be devoid of microorganisms?
LUDY MAE B. NALZARO, BSM, RN, MN 73
74. Of all the various areas of microbiology
mentioned in this chapter, which
appeal to you the most?
Why?
LUDY MAE B. NALZARO, BSM, RN, MN 74
75. Assume that you are entering a health-related
profession.
Of what value will knowledge of
microbiology be to you?
LUDY MAE B. NALZARO, BSM, RN, MN 75
76. Many people consider Louis Pasteur’s
contributions to be the foundation of the
science of microbiology and a cornerstone
of modern medicine.
What contributions did he make that would
cause people to believe that?
LUDY MAE B. NALZARO, BSM, RN, MN 76
77. You have isolated a bacterium from the blood
of a patient with a newly described disease.
What steps would you take to prove that the
organism that you’ve isolated is the cause
of the patient’s disease?
(Hint: Remember Koch’s Postulates.)
LUDY MAE B. NALZARO, BSM, RN, MN 77
Editor's Notes
Requirements: Look for an article in the net or newspaper about certain outbreak in a certain community. Identify its chain of infection.
