Why study microbes

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Game Plan
Lecture Why study microbes? Early microscopic
observations Germ theory of disease Naming
Categorization
Lab Introduction Microscopes and
measurements Pre-lab Aseptic technique Microbes
in the environment
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Why study microbes??
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Why study microbes??
INFECTIOUS DISEASE!
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Why study microbes??
INFECTIOUS DISEASE!

• Salmonella outbreak
• 2008-2009 474 people infected with Salmonella
  serotype
• Typhimurium from peanut butter produced by Peanut
  Corporation of
• America (PCA). 
• Staph infections at Miramar
• 2008 Recruits in the police academy contracted
  staph infections  
• likely caused by the mat surface and spread by
  skin to skin contact
•    
• XDR-TB in the USA
• 2007 Extensively drug resistant tuberculosis
  (XDR-TB) in US
• airline passenger extensively in California
• DRUG RESISTANT BACTERIAL OUTBREAKS
• MRSA (methicillin-resistant Staphylococcus
  aureus)
• C. diff (Clostridium difficile)

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Recent infectious disease outbreaks
International Society for Infectious Diseases
PRO/AH/EDRgt Yellow fever - South America (08)
Brazil (RS) monkey, susp.
January 22, 2009
PRO/AH/EDRgt Salmonellosis, serotype Typhimurium -
USA (07) peanut butter
PRO/AH/EDRgt Undiagnosed illness, bovine -
Cambodia (PO), RFI
PRO/EDRgt Cholera, diarrhea dysentery update
2009 (09)
January 21, 2009
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Emerging and re-emerging infectious diseases

• Definition New or changing diseases that are
  increasing in incidence
• or have potential to increase in the near future
• - Avian influenza A (H5N1)
• - Creutzfeldt- Jakob disease (CJD)- mad cow
  disease
• - Invasive Group A Streptococcus- flesh eating
  bacteria
• - Methicillin-resistant Staphylococcus aureus
  (MRSA)
• - Multidrug-resistant Mycobacterium tuberculosis
  (TB)
• - Hypervirulent drug-resistant Clostridium
  difficile

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What organisms cause disease?
Catalogued human pathogens Bacterial
538 Fungal 317 Helminthic 287 Viral 208 Proto
zoan 57 (Prions and viroids)
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Why study microbes??

• INFECTIOUS DISEASE!
• Epidemiology frequency and distribution of
  diseases (CDC, MMWR, ISID, etc.)
• Immunology study of immune system to prevent
  disease
• Edward Jenner and vaccinations

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Why study microbes??

• 2. Biotechnology
• - Food and industrial compound production

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Why study microbes??

• 2. Biotechnology
• - Food and industrial compound production
• Chemotherapy treatment of disease with a
  chemical
• Synthetic drugs- man-made chemicals
• Ex. Paul Erlichs magic bullet
  salvarsan against syphilis (1910) Gerhard
  Domagks sulfa drugs (1930s)
• Antibiotics- microbe-made chemicals
• Ex. Alexander Flemings penicillin
  from Penicillium notatum

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Why study microbes??

• 2. Biotechnology
• - Food and industrial compound production
• Chemotherapy treatment of disease with a
  chemical
• Synthetic drugs- man-made chemicals
• Ex. Paul Erlichs magic bullet
  salvarsan against syphilis (1910) Gerhard
  Domagks sulfa drugs (1930s)
• Antibiotics- microbe-made chemicals
• Ex. Alexander Flemings penicillin
  from Penicillium notatum
• Genetic manipulation
• Genetic engineering
• Gene therapy
• Microbial insecticides

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Why study microbes??

• Environmental
• Bioremediation- use of microbes or their enzymes
  to degrade,
• detoxify, or otherwise decontaminate
  environmental hazards

Berlin biotechnology company uses
fungus Penicillium jantinellum to degrade plastic
in Trabant car
Pseudomonas spp. metabolize oil spill on Alaskan
shore
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Why study microbes??
4. Microbiota - We are made up of more
bacterial cells than human cells! -
Roles Maintain health intestinal and vaginal
tracts, skin Cause disease oral microbiota,
overuse of antibiotics, opportunistic pathogens
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How do we study microbes??

• We observe them
• 2. We characterize them
• 3. We name them
• 4. We categorize them

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Observation- Spontaneous generation

• 4th century BC
• Aristotle proposes that decaying
• material could be transformed by
• the spontaneous action of Nature into
• living animals
• Examples
• Nile floods- frogs appear
• Carcass hangs in butcher shop- maggots appear
• Rain falls through thatched roof-
• spoils grain- mice appear
• Recipe for mice (Jan Baptista van Helmont, 1500s)
• Put dirty rag in a pot with grain and 21 days
  later you will have mice

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Observation- The microscope circa late 1600s
Robert Hooke and Anton van Leeuwenhoek
Figure 1.2
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Biogenesis- Omne vivum ex vivo, OR no life
without antecedent life

• 1668- Francesco Redi

1837- Schwann (Schultze)
1864 Pasteur
1768- Spallanzani
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Characterization- Germ theory of disease
1840s- Ignaz Semmelweis and handwashing

• 1860s- Joseph Lister and chemical
• disinfectants in surgery

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Characterization- Germ theory of disease and
Kochs postulates

• Kochs postulates (1884)
• The same organism must be present in every
• case of the disease
• The organism must be isolated from the
• diseased host and grown in pure culture
• The isolate must cause the disease when
• inoculated into a healthy, susceptible animal
• The organism must be re-isolated from the
• inoculated diseased animal
• (page 426)

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Naming- Binomial nomenclature
1730s Carolus Linnaeus
Genus species Escherichia coli or E. coli
Staphylococcus aureus or S. aureus Rickettsia
rickettsii or R. rickettsii
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Categorization
Kingdoms of Life Monera Archaea Bacteria Protist
a Fungi Plantae Animalia
Domains of Life Archaea Bacteria Eukarya
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Independent Study

• What factors are crucial in determining the
  probability of a
• disease being an EID or a re-EID?
• Which species of microbe are involved in the
  production of
• - Wine
• - Bread
• - Yogurt
• - Swiss cheese
• - Streptomycin
• What category do each of these microbes belong
  to bacteria,
• archaea, fungi, algae, or virus?