1. Prokaryotes vs. Eukaryotes

3. The Endosymbiotic Theory

4. Why study prokaryotes?

5. They cause disease

6. Why study prokaryotes? They cause disease True, but most prokaryotes want nothing to do with humans

7. Why study prokaryotes that don’t cause disease?

8. Prokaryotes were the first living organisms on the planet

9. Prokaryotes live everywhere life is possible

12. Enzymes useful for medical or industrial uses may be discovered in prokaryotes living in extreme environments

13. Prokaryotes likely constitute the largest component of the planet’s biomass

14. Entire ecosystems depend on their activities

15. Prokaryotes play a vital role in the ecosystem

16. Prokaryotes are required for the cycling of nutrients throughout the environment

17. The carbon cycle

18. The nitrogen cycle

19. The sulfur cycle

20. The iron cycle

21. Louis Pasteur

22. Discovered that wine was souring due to bacterial contamination

23. Louis Pasteur Discovered that wine was souring due to bacterial contamination Specific microorganisms are responsible for specific changes in chemical compounds

24. Louis Pasteur Discovered that wine was souring due to bacterial contamination Specific microorganisms are responsible for specific changes in chemical compounds Sugar  ethanol (yeast) Sugar  lactic acid (bacteria)

25. Louis Pasteur and Robert Koch

26. Robert Koch Aseptic slices of potato used as first solid media

27. Robert Koch Aseptic slices of potato used as first solid media Gelatin used as solidifier Agar suggested by wife of Koch’s assistant

28. Robert Koch Petri invented dishes to pour agar into

29. Many microorganisms either cannot grow in artificial media or are at very low concentrations compared to other microorganisms

30. Sergei Winogradsky and Martinus Beijerinck developed enrichment techniques and selective media

31. Sergei Winogradsky Discovered that bacteria can oxidize iron, sulfur and ammonium to obtain energy Discovered that some bacteria can fix CO 2 like photosynthetic plants

32. Winogradsky column Used to isolate photosynthetic organisms

33. Winogradsky column Used to isolate photosynthetic organisms Column packed with mud, sulfur, carbonate and cellulose Column exposed to light

34. Winogradsky column Different organisms grow at different layers Samples from different layers plated on selective media

35. Prokaryotes often live in complex communities Biofilms

36. Prokaryotes often live in complex communities Microbial mat Stromatolites