1 / 24

Virus structure, classification and replication

Virus structure, classification and replication. Viruses defined. Obligate intracellular parasites. Under attack!. (From Medical Microbiology, 4 th ed., Murray, Rosenthal, Kobayashi & Pfaller, Mosby Inc., 2002, Fig. 65-1.). Structures compared.

emil
Télécharger la présentation

Virus structure, classification and replication

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Virus structure, classification and replication

  2. Viruses defined Obligate intracellular parasites

  3. Under attack! (From Medical Microbiology, 4th ed., Murray, Rosenthal, Kobayashi & Pfaller, Mosby Inc., 2002, Fig. 65-1.)

  4. Structures compared From Medical Microbiology, 5th ed., Murray, Rosenthal & Pfaller, Mosby Inc., 2005, Fig. 6-4.

  5. DNA or RNA Basic virus structure Capsid protein Naked capsid virus Nucleocapsid + = Lipid membrane, glycoproteins Nucleocapsid Enveloped virus +

  6. Matrix Lipid Glycoprotein Capsid symmetry Icosahedral Helical Naked capsid Enveloped

  7. Adenovirus Electron micrograph Foot and mouth disease virus Crystallographic model Icosahedral naked capsid viruses http://virology.wisc.edu/virusworld/ICTV8/fmd-foot-and-mouth-ictv8.jpg http://www.ncbi.nlm.nih.gov/ICTVdb/Images/Ackerman/Animalvi/Adenovir/799-16.htm

  8. Helical naked capsid viruses RNA Protein http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/em_tmv.gif Caspar and Klug, Adv Virus Res. 1960;7:225-325 Tobacco mosaic virus Electron micrograph Tobacco mosaic virus Model

  9. Icosahedral enveloped viruses http://web.uct.ac.za/depts/mmi/stannard/emimages.html http://virology.wisc.edu/virusworld/images/herpescapsid.GIF Herpes simplex virus Electron micrograph Herpes simplex virus Nucleocapsid cryoEM model

  10. Helical enveloped viruses http://web.uct.ac.za/depts/mmi/stannard/fluvirus.html http://web.uct.ac.za/depts/mmi/stannard/paramyx.html Influneza A virus Electron micrograph Paramyxovirus Electron micrograph

  11. Taxonomy of the Order Mononegavirales a V, vertebrate; I, insect; P, plant. Fields Vriology (2007) 5th edition, Knipe, DM & Howley, PM, eds, Wolters Kluwer/Lippincott Williams & Wilkins, Philadelphia Table 2.2

  12. Classification of Human Viruses Fields Vriology (2007) 5th edition, Knipe, DM & Howley, PM, eds, Wolters Kluwer/Lippincott Williams & Wilkins, Philadelphia Table 2.1

  13. Major diseases caused by human viruses

  14. Virus replication: general

  15. Virus replication:variations on the theme • dsDNA • ssDNA • (+)ssRNA • (-)ssRNA • dsRNA • RNA retro • DNA retro

  16. dsDNA virus replication (+)mRNA dsDNA dsDNA

  17. (+)mRNA (+) ssDNA dsDNA ssDNA virus replication

  18. (+)RNA (+)RNA (-)RNA (+)ssRNA virus replication

  19. (+)mRNA (+)RNA (-)RNA (-)RNA (-)ssRNA virus replication

  20. (+)mRNA dsRNA dsRNA dsRNA virus replication

  21. (+)mRNA (+)mRNA ssDNA (+)RNA (+)RNA dsDNA (+)ssRNA retrovirus replication

  22. (+)mRNA (+)mRNA ssDNA (+)RNA dsDNA dsDNA dsDNA retrovirus replication

  23. Virus growth 1,000 – 100,000 viruses/cell, 5 – 24 hours From Schaechter’s Mechanisms of Microbial Disease; 4th ed.; Engleberg, DiRita & Dermody; Lippincott, Williams & Wilkins; 2007; Fig. 31-8

  24. Summary: structure,classification & replication • Structure • Nucleic acid in a protein shell, +/- lipid envelope • Structure impacts on biological properties • Classification • Many virus families, organized by structure and biology • Replication • Generic scheme • Varying strategies depending on nucleic acid

More Related