Microbiology for nursing students Introduction to microbiology History of microbiology

1. Microbiology
An introduction to microbiology
designed for allied health majors
By BugLady

2. How to Ace this Class
Book and slides are no substitute for active
engagement
Participate: post questions and ask for help
Don’t wait to ask
Take notes aka active learning
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3. Writing Essays
Take brief notes as you go
Record all references
Create an outline
Rewrite information in your own words Use peer-review
or credible sources
 PMC: full length, peer-reviewed articles
 HON: Health on the Net; look for badge on the website
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4. Introduction to Microbiology
Overview of course
What is microbiology?
History of microbiology
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5. Course Overview
Biochemistry and Microscopy
Biology of microorganisms
Metabolism
Growth and Ecology
Containment of Microorganisms
Genetics and Bioengineering
Mutations and Bacterial Recombination
Viruses
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6. Course Overview
Antibiotics
Innate Immune System
Adaptive Immune System
Host Microbe Interactions
Disorders of the Immune System
Epidemiology
Classification
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7. Microbiology
Microbiology is the study of all the
organisms that are too small to be seen
with the naked eye (<0.1mm)
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8. Size of Particles and
Microorganisms
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Limit of light microscope

9. Why Study Microbiology?
Impact on human life
Decomposers
Microbes are ubiquitous: soil, water, ice cap,
hot vents, body
Extremely adaptable
Simple models to study biological processes
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10. Positive Impact on Human Life
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Microbiome Decomposers
Food source Ecological balance
Antibiotics and other
chemicals
Biodegradation
Bioengineering Bioremediation

11. Negative Impact on Human Life
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Pathogens (disease causing agents)
Food spoilage
Corrosion
Bad smells

12. Scientific Names
Escherichia coli
o Honors the discoverer, Theodor Escherich, and
describes the bacterium’s habitat, the large intestine
or colon.
Staphylococcus aureus
o Describes the clustered arrangement of the cells
(staphylo-) and the golden color of the colonies.
After the first use, scientific names may be abbreviated with
the first letter of the genus and the species:
• Staphylococcus aureus and Escherichia coli are found in the human body: S
aureus on skin and E coli in the large intestine.
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13. Use of Latin
One bacterium – many bacteria
One medium – several media
One bacillus – many bacilli
One staphylococcus – many
staphylococci
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14. Two Empires and Three Domains
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Pathogens are disease causing agents or
organisms

15. Prions
Prions Proteinaceous infectious particles
Diseases linked to the presence of prions
are transmissible spongiform
encephalopathies (e.g. mad cow disease).
Misfolded proteins
Slow infection (20-30 years)
No cure
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16. Viruses
Not cells
Will not propagate on their own
No metabolism
Contain genetic/protein material
Phages, tobacco mosaic virus,
HIV, causative agents of common
cold, flu, polio, chicken pox
Viruses infect organisms from the
3 domains of life
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National Institute of General Medical Sciences

17. Three Domains
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http://www.ucmp.berkeley.edu/exhibits/historyoflife.php

18. Prokaryotes and Eukaryotes
Prokaryote = no nucleus
Archaea and Bacteria are prokaryotes
Eukaryote = true nucleus
Protists, plants, fungi, and animals are
eukaryotes
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19. Archaea are Prokaryotes
No true nucleus, no organelles, 1-5µ length
Classified as Bacteria until 1979
Molecular structures closer to Eukaryotes
Eukaryotes and Bacteria diverged from
Archaea
Oldest known organisms on Earth.
o Fossil records show over 3.6 BILLION years ago
No known pathogens
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20. Extremophiles
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Hydrothermal vent
Courtesy: NASADead Sea Courtesy: EXACT-ME
Geyser
Courtesy: Volcano Hazards
Team/USGS
Polar ice Courtesy: NOAA

21. Bacteria
Bacteria are unicellular microscopic organisms that
lack a true nucleus.
Less than 10% of bacteria cause diseases
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Staphylococcus epidermidis Neisseria sicca

22. Bacteria or Eubacteria
Bacteria grow in a wide variety of habitats
and conditions.
Bacteria have a wide range of environmental
and nutritive requirements.
Bacteria play important roles in the global
ecosystem.
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23. Bacteria
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Bacilli
Escherichia coli
Courtesy: Public Health Library
Courtesy: Environmental Protection Agency

24. Eukarya
The word 'eukaryote' means 'true nucleus’
Eukaryotes contain a true nucleus and membrane-
bound organelles
Nucleus: genetic material
Organelles:
o specific function
o subcellular structures bound by membranes
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25. Protists
Unicellular or poorly differentiated organisms
Plankton, flagellates, protozoa, algae…are all
protists.
Important infectious diseases are caused by
parasitic protists: malaria, sleeping sickness,
dysentery
Red tide causes poisoning
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Trypanosoma brucei gambiense
Courtesy of CDC
Cyclospora cayetanensis
Courtesy of CDC

26. Fungi
Use organic materials for energy
Both multicellular (molds and mushrooms) and
unicellular - single cell- (yeasts) organisms
Source of antibiotics, food, bread and alcohol
Mycosis are fungal infections
o Pneumocystis (pneumonia in HIV patients), tinea
(athlete’s foot), thrush
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Courtesy: CDC

27. Helminthes
Helminthes are parasitic worms
o Tape worms, flukes, pinworms
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Courtesy of the Public Health Library

28. Review
http://www.quia.com/rr/240939.html
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29. History of Microbiology
The Golden Ages
1850s: Gram, Pasteur, Koch…
1940-1950s: antibiotics
Now: Microbiome, metagenomics,
probiotics, asthma, MS, RA

30. History of Microbiology I
The Golden Age (mid-19th century)
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Scientific Discovery Technical Progress
Cell theory – Schwann, Virchow
1858
Growth media – Koch’s Lab
1880s
Disproving spontaneous
generation – Pasteur 1865
Staining protocols – Gram 1884
Postulate rules – Koch 1890 Disinfection - Semmelweis
1847 Lister 1867
Development of vaccines-
Jenner 1796
Sterilization procedures – 1879
Tyndall, Pasteur’s Lab

31. The First Observations
Antoni van Leeuwenhoek
(1673-1723)
Described live
microorganisms in teeth
scrapings, rain water, and
peppercorn infusions.
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Figure 1.2b

32. Vaccination
1796: Edward Jenner and cowpox
Called vaccination from vacca for cow
The protection is called acquired immunity
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33. The Debate Over Spontaneous
Generation
Spontaneous Generation:
oLiving organisms arise
from nonliving matter.
Biogenesis
oLiving organisms arise
from preexisting life.
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Louis Pasteur

34. Louis Pasteur
Pasteur developed swan necked flask to show
that air is filled with microbes
Was able to demonstrate infusions remained
sterile even if flask was left open
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Original sketches of Pasteur (1861)

35. The Germ Theory of Disease
Pasteur’s work showed microbes are in the air, can
spoil food, and cause animal diseases
Joseph Lister (1860s)
o used a chemical disinfectant to prevent surgical
wound infections.
Robert Koch (1876)
o provided proof that a bacterium causes
anthrax
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36. Koch’s Postulates
The agent must be present in every case of
infection and absent from healthy individuals
The agent can be isolated from infected organism
and grown in a pure culture
The disease can be reproduced by inoculating a
healthy organism with a pure culture
The agent can be isolated from the newly
infected organism
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37. Jul-14 37
Courtesy: CDC Adapted from: Hosp Epidemiol Infect Control, 2nd Edition, 1999

38. History of Microbiology II
Antibiotics 1940-current
Biotechnology 1978-current
Genetics 1920-current
Human Microbiome Project
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39. Gentlemen, microbes will have the last
word!
“…It is time to close the book on infectious diseases…”
William Stewart, US Surgeon General in a message to Congress
1969
Antibiotics resistance
The big 3: TB, HIV, malaria
Microbiome, obesity, allergies
New threats: Health Acquired Infection (HAI), MERS,
H7N9, Ebola virus
Ecological balance
Bioremediation
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