BIODIVERSITY I BIOL 1051 What are Viruses?

1. BIODIVERSITY IBIOL 1051What are Viruses? Professor Marc C Lavoie mlavoie@uwichill.edu.bb

3. What are Viruses?

4. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

5. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

6. 1. Viruses are very very small

7. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

8. 2. Viruses are NOT cells. • Obligate intracellular parasites • Small- filterable through bacteriological filters • Contain a single type of nucleic acid, either DNA or RNA • Contain a protein coat (the capsid) consisting of individual protein units (capsomeres) • May contain a host-derived lipid membrane (the envelope) through which may be inserted viral proteins (spikes or peplomeres) • Multiply inside living cells by using the biosynthetic machinery of the host

9. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

10. 3. Size and shape of viruses Icosahedral (20 faces) symmetry

11. 1.3 Size and shape of viruses

12. Poliovirus Foot & Mouth Disease Virus (FMDV) 3. Size and shape of viruses

13. 3. Size and shape of viruses Helical symmetry

14. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

15. 4. Viral structures

16. 4. Viral structures

17. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

18. 5. Virus multiplication

19. 5. Virus multiplication

20. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

21. 6. Virus diversity

22. 6. Virus diversity(Baltimore classification)

23. What are Viruses? • 1. Viruses are very very small • 2. Viruses are NOT cells. • 3. Size and shape of viruses • 4. Viral structures • 5. Virus multiplication • 6. Virus diversity • 7. Viroids and Prions

24. 7. Viroids

25. 7. Viroids Potato Spindle Tuber Viroid

26. 7. Prions

27. 7. Prions PrP C : host-derived prion protein PrP SC : Infectiousconformational isomer

28. 7. Prions

29. 7. Prions: Reproduction theories

30. What are Viruses? • REFERENCE:MADIGAN, MT, MARTINKO, JM, & PARKER, J. Brock Biology of Microorganisms, 10th ed, 2003, PRENTICE HALL, p.231-265. • PURVES, WK, SADAVA, D, ORIANS, GH, HELLER, HC. Life, The Science of Biology, 6th ed, 2001, Sinauer Assiciates Inc., p. 239-244. • Charles Weissmann,THE STATE OF THE PRION, NATURE REVIEWS,MICROBIOLOGY VOLUME 2 | NOVEMBER 2004 | 861-871

31. Lecture 4: What are Viruses? • WEB sites: • http://library.thinkquest.org/13373/intro/intro.htm • http://www.tulane.edu/~dmsander/WWW/224/Classification224.html • http://www.bocklabs.wisc.edu/ed/genomes.gif • http://www.tulane.edu/~dmsander/WWW/224/Classification224.html • http://www.uct.ac.za/microbiology/tutorial/other_autonomous_or_semi.htm • http://www.uct.ac.za/microbiology/tutorial/other_autonomous_or_semi.htm • Russell Kightley Media • http://www.mad-cow.org/prion_evol.html