1. Microorganisms Bacteria and Viruses Chapter 19

2. Review  Prokaryote and Eukaryote  Cell Structure and Function  Classification

3. Prokaryotes Classifying Prokaryotes Kingdoms  Eubacteria  Archaebacteria

4. Kingdom Archaebacteria  3.5 billion years ago  Characteristics Unusual lipids in their cell membrane DNA similar to eukaryotes No peptidoglycan in their cell wall

5.  Categories of Archaebacteria Methanogens  Use hydrogen gas  Reduce carbon dioxide to methane Extremophiles  Thermophiles (60-80 o C)  Halophiles Non-extremophiles  Same environment as eubacteria, DNA is unique

6. Kingdom Eubacteria  Shapes Bacilli  Straight rod Cocci  spherical Spiral  Long and spiral Groupings  Staph- graph cluster  Strep - chain

7. Gram Staining Bacteria Steps: 1. crystal violet 2. iodine stain 3. alcohol wash 4. safranin Positive = purple Negative = pink

8. Gram Positive Bacteria Gram Negative Bacteria Mixed Bacteria

9. What Gram Indicates  Difference in the cell wall (peptidoglycan) Why Gram Stain?  Determines antibiotic efficiency  Indicates different toxins  React to disinfectants differently

10. Structure of Bacteria

11. The Biology of Eubacteria  Cell Wall Peptidoglycan protection  Cell membrane and Cytoplasm Lipids and enzymes surface area ribosome

12.  Pili Hair-like outgrowths for attachment  Endospore Thick wall around the chromosome during unfavorable growth conditions Resistant Live for decades!  Bacillus and Clostridium strains

13.  Movement Flagella  Run and Tumble slime  Obtaining Energy Autotrophs Heterotrophs

14.  Releasing Energy Obligate anaerobes  Clostridium botulinum Facultative anaerobes  Escherichia coli Obligate aerobes  Clostridium tuberculin

15.  Reproduction and Growth Binary Fission  Identical clones Transformation Transduction Conjugation  Two living bacteria bind and one transfers genetic information to the other through a sex pili  Creates genetic diversity

16. Bacteria in Nature Decomposers  Recycle nutrients in the ecosystem  Sewage treatment Nitrogen Fixers  Converting nitrogen gas into a usable form for the production of amino acids

17. Bacteria and Disease  Pathology – study of disease  Pathogens Damage to tissues Release of toxins  Exotoxins (Gram+, Clostridium tetani)  Endotoxins (Gram-, Escherichia coli)

18. Modes of Transmission 1. Airborne legionellosis, pertussis, diphtheria 2. Animal lyme disease, bubonic plaque 3. Direct Contact gonorrhea, anthrax 4. Food or Waterborne salmonella, cholera, diarrhea

19.  Antibiotics Drugs to combat bacteria only! Complete entire course of medication Water is essential Check Gram +/- status  Resistance Abuse and Misuse Evolution mutations

21. Human Uses of Bacteria  Soil  Food  Industry  Biotechnology

22. Viruses Latin word for POISON What is a virus?  Wendell Stanley Not living! Nucleic acid and protein Cause infection Take over the machinery of their host Tobacco Mosaic Virus

23. Viruses are not members of the Six- Kingdom System of Classification Detached Fragment of a genome Infect all taxonomic levels! They are highly specific

24. Characteristics  Size Smallest biological particle 17 nm to 1000 nm  Structure Not cellular Nucleic acid (DNA or RNA) Protein coat  Shape Helical or isometric

25. Bacteriophage Infect bacteria DNA Example: T4 phage

26. Viral Infection Lytic Cycle - Virulent 1. Attachment 2. Entry 3. Replication

27. 4. Assembly 5. Release  lysis!

28. http://www.cat.cc.md.us/courses/bio141/le cguide/unit2/viruses/adlyt.html http://www.cat.cc.md.us/courses/bio141/le cguide/unit2/viruses/adlyt.html

29. Lysogenic Cycle - temperate

30. Lysogenic Cycle  Stages 1. Attachment 2. Injection 3. Integration of Prophage 4. Cell multiplication 5. Conversion * May stay dormant for many a unknown period of time

31. http://www.cat.cc.md.us/courses/bio141/le cguide/unit2/viruses/lysosum.html http://www.cat.cc.md.us/courses/bio141/le cguide/unit2/viruses/lysosum.html

32. Viruses and Disease  Vaccine protection Attenuated Inactivated  Oncogenic viruses  Retroviruses  Prions Stanley Prusiner Scrapie, BSE, CJD

33. Lysogeny of HIV Typical animal virus Cause of Acquired Immune Deficiency Syndrome (AIDS) US since 1981 Virus closely related to a chimpanzee virus Persons die from opportunistic infections