Chapter 18 Genetics of Viruses and Bacteria

1. Chapter 18Genetics of Viruses and Bacteria

2. Chapter 18Genetics of Viruses and Bacteria Viruses: • are much smaller than bacteria • consist of a genome in a protective coat • reproduce only within host cell • use enzymes and ribosomes of host to make more viruses

3. Chapter 18Genetics of Viruses and Bacteria Lytic cycle: Lysogenic cycle:

4. Chapter 18Genetics of Viruses and Bacteria Lytic cycle: Virus destroys host DNA, makes new viruses, digests cell wall Lysogenic cycle: Virus inserts DNA into host genome (becoming a dormant prophage). Generations later, virus reactivates.

5. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

6. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

7. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

8. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

9. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

10. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

11. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

12. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

13. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

14. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

15. Chapter 18Genetics of Viruses and Bacteria Lytic cycle:

16. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

17. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

18. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

19. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

20. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle: prophage

21. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

22. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

23. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

24. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

25. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

26. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

27. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

28. Chapter 18Genetics of Viruses and Bacteria Lysogenic cycle:

29. Chapter 18Genetics of Viruses and Bacteria Animal Viruses: • are diverse in their means of infection • often have an envelope acquired from cell membrane.

30. Chapter 18Genetics of Viruses and Bacteria Retroviruses: • made of RNA • use reverse transcriptase to make DNA from RNA template • DNA inserts into host genome as dormant provirus.

31. Chapter 18Genetics of Viruses and Bacteria Emerging viruses: • existing viruses that are expanding their host territory.

32. Chapter 18Genetics of Viruses and Bacteria Viroids: • naked RNA Prions: • infectious proteins • mad cow disease.

33. Bacteria Plasmids: • Small rings of DNA with accessory genes

34. Bacteria Plasmids: • Small rings of DNA with accessory genes. chromosome plasmid

35. Bacteria Transformation:

36. Bacteria Transformation: • Bacteria take up naked DNA

37. Bacteria Transformation: • Bacteria take up naked DNA

38. Bacteria Transformation: • Bacteria take up naked DNA

39. Bacteria Transduction:

40. Bacteria Transduction: • Phages carry bacterial DNA

41. Bacteria Transduction: • Phages carry bacterial DNA

42. Bacteria Transduction: • Phages carry bacterial DNA

43. Bacteria Transduction: • Phages carry bacterial DNA

44. Bacteria Transduction: • Phages carry bacterial DNA

45. Bacteria Conjugation:

46. Bacteria Conjugation: • Bacteria “mate” to share DNA

47. Bacteria Conjugation: • Bacteria “mate” to share DNA

48. Bacteria Conjugation: • Bacteria “mate” to share DNA

49. Bacteria Conjugation: • Bacteria “mate” to share DNA

50. Bacteria Conjugation: • Bacteria “mate” to share DNA