1. Bacteria “bacteria by Jonathan Coulton

2. Objectives Define Bacteria, eubacteria, & archaebacteria, and note the relationships between them. Methods used to classify bacteria Describe 3 types of archaebacteria Gram-positive vs. Gram-negative bacteria Structure of a bacteria cell How they move Bacterial genetic recombination

3. It’s their planet, they were here first, and there’s more of them than us. They’re microscopic prokaryotes –No nucleus, ect… The bacteria save us in War of the Worlds

4. Evolution They’ve been evolving for 3.5 billion years, that’s a lot of time to turn into different species. They’ve found ways to survive almost everywhere. Some can “hibernate” in space –Leads to interesting ideas

6. How many? 40 million bacteria in a gram of dirt 1 million in a mL of fresh water 5x10 30 bacteria in the world Your body has 10x’s more bacteria cells than human cells in it

7. Classification A lot of bacteria look pretty much alike Group them on… –Structure, physiology, how they react to dif. Types of staining techniques OR group them on RNA similarity

9. Why did the bacteria cross the microscope? To get to the other slide.

10. Two kinds of bacteria Eubacteria Archaebacteria –More ancient group

11. Archaebacteria Have weird lipids on their membranes Have introns in their DNA Have NO Peptidoglycan –A protein/carb mix

12. Extremophiles Love extremes No competition there Places to salty, acidic, hot or cold, for life

13. Methanogens Oxygen kills them Live at bottom of swamps, or in sewage Can combine O 2 and CO 2 into methane –Swamp gas And in your gut –Enteric bacteria –E. Coli  a facultative anaerobe: It can live with or without O 2 –Obligate anaerobes: Have to live where there’s no O 2

14. Halophiles & Acidophiles Halophiles: Love salt –Live in the dead sea –2 nd saltiest water on Earth –8x’s saltier than oceans –Lowest point on earth not covered by ice –418 M below sea level

15. Dead Sea King David, Herod, Jesus, John The Baptist, Jericho is just north (oldest continually occupied town But the sea is shrinking –People need water

16. Volcanic acid lake in Gorley (Kamchatka, Russia) A crowbar will dissolve in about an hour in this lake

17. Acid Lake in Taal, Phillipines Sulfuric vents at the lake’s edge

18. Eubacteria Rod shaped: Bacilli Sphere shaped: cocci –Linked in a chain: streptococci –Grape-like clusters: staphylococci Spiral shpaed: Spirilla

19. Gram Stain Gram-positive: keep the stain, show up purple –They have peptidoglycan –These bacteria make yogurt Gram-negative: don’t take the gram stain, but do take a pink stain instead –Rhizobium: makes N 2 gases usable by plants The difference: Make dif, chemicals, react to dif antibiotics and disinfectants

20. Cyanobacteria Not plants, but do photosynthesis Heterocysts: a kind that makes Nitrogen usable for plants If you put a lot of nitrogen into a water supply you get a population bloom –Eutrophication: all these bacteria suck up the oxygen and everything else in the water dies

22. Genetic recombination Without reproducing bacteria can acquire and express new genetic info Transformation: Bacteria take in DNA around it Conjugation: Bacteria use pilli to make a bridge between each other and uses plasmids Transduction: viruses carry DNA between bacteria