1. An intro to bacteria, infectious diseases, and antibiotic resistance
SUPERBUGS
Image: Wikipedia (
An intro to bacteria, infectious diseases, and antibiotic resistance

2. What are bacteria? Single-celled organisms
Prokaryotes: genetic material NOT contained in a nucleus
Auto-trophs and hetero-trophs
Defined as having no nucleus or membrane bound organelles
1-10um in diameterMost have cell walls
Contain a single circular chromosome found in the nucleoid region (and plasmids which are small, circular segments of DNA)
Small ribosomes
Formed about 3.5 billion years ago
An autotroph is an organism that produces complex organic compounds (such as carbohydrates, fats, and proteins) from simple inorganic molecules using energy from light (by photosynthesis) or inorganic chemical reactions (chemosynthesis).
A heterotroph (Greek heteros = "another” or "different" and trophe = "nutrition") is an organism that uses organic carbon for growth.
Left:
Right:

3. How abundant are bacteria?
Bacterial Abundance
Total bacteria on Earth
5 x 1030
Number of stars in the universe
7 x 1022
Age of the universe in seconds
4.4 x 1017
Bacteria in the human gut
1 x 1014
Global gross product ($/year)
7 x 1013
Cells in the human body
1 x 1013
Texts sent in 2009
1.5 x 1012
People on Earth
6.9 x 109
10X
“Abundance” = how many…
Notice that there are 10 times more bacterial cells in your gut alone than there are human cells in your entire body!
Do you think you are sick because they are there, or that you are healthy because they are there?

4. All about bacteria… Help make yogurt, cheese, & wine
Involved in environmental recycling and clean-up
Bacteria live almost anywhere and eat almost anything!!
Left: Image of advertisement of live bacterial cultures in yogurt (
Center: Heterotrophic bacteria (
Right: Cyanobacteria Oscillatoria (

5. How many types of bacteria are there?
Bacterial Distribution
Insect Species
1-10 million
Bacterial species in the soil
4 million
Bacterial species in the air
Bacterial species in the ocean
2 million
Bird Species
10,000
Bacterial species in the human mouth
600
Bacterial Species in the human gut
500
Pathogenic Species 55
Type = species
Note that there are really few harmful bacteria compared to all others. MOST BACTERIA ARE HARMLESS OR HELPFUL!

6. Infectious Diseases Pathogen: a biological agent that causes disease
Can be a virus, bacteria, fungi, protozoa, or parasite
Infectious diseases are communicable or transmissible from one person to another
Pathogens are microorganisms that make you sick/ill.

7. Protist: Malaria (Plasmodium)
Virus: Influenza (H1N1)
Protist: Malaria (Plasmodium)
Fungi: Plant pathogen (Rigidoporus laetus)
H1N1 Virus:
Marlaria:
Fungi:

8. Staph Infection: Staphylococcus aureus
Mycobacterium tuberculosis
Salmonella typhimurium
Tuberculosis:
Salmonella:
Staph:

9. Antibiotics Compounds that kill bacteria or inhibit their growth
Naturally produced by microorganisms to kill others
Now many are made synthetically
Antibiotics are used to treat bacterial infections.
Antimicrobials are a broader class of chemical/compounds that kill bacteria, fungi, and protists.
Antibiotics can kill a bacteria in several different ways. Some target DNA or protein synthesis, others interrupt the cell membrane.
Prontosil, the first commercially available antibacterial antibiotic was developed by a research team led by Gerhard Domagk (who received the 1939 Nobel Prize for Medicine for his efforts) at the Bayer Laboratories of the IG Farben conglomerate in Germany.
The development of penicillin led to renewed interest in the search for antibiotic compounds with similar capabilities.[17] Because of their discovery of penicillin Ernst Chain, Howard Florey and Alexander Fleming shared the 1945 Nobel Prize in Medicine.

10. Antibiotics Susceptible vs. Resistant Lawn Antibiotic Clearing
Susceptible: likely to be influenced by
Resistant: drug does not work on the bacteria (no longer kills it)
Image:
Clearing

11. Why is resistance bad? Because you can’t treat the disease!
The patient will remain sick 

12. How do you get resistance?
Usually from mutation in DNA
Genetic mutations can be passed to offspring…
Leads to evolution!
Evolution is the change in the inherited traits of a population of organisms through successive generations. (Changes in a population over time).

13. Genetic Mutation
NATURAL SELECTION!

14. Susceptible
+ Antibiotic
Antibiotic Resistant

15. What can you do to help? Follow the directions!
Take antibiotics only when necessary