Introduction to virology
This presentation is the property of its rightful owner.
Sponsored Links
1 / 35

Introduction to Virology PowerPoint PPT Presentation


  • 126 Views
  • Uploaded on
  • Presentation posted in: General

Introduction to Virology. I. Objectives. What is a virus How do viruses multiply How are viruses classified (What are some of the diseases viruses cause). II. Historical Perspective. A. Ancient times 1. poliovirus 2. smallpox B. More recent history 1. 1790’s Iwanowski 2. 1890’s

Download Presentation

Introduction to Virology

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Introduction to virology

Introduction to Virology


I objectives

I. Objectives

  • What is a virus

  • How do viruses multiply

  • How are viruses classified

  • (What are some of the diseases viruses cause)


Ii historical perspective

II. Historical Perspective

  • A. Ancient times

    • 1. poliovirus

    • 2. smallpox

  • B. More recent history

    • 1. 1790’s

      • Iwanowski

    • 2. 1890’s

      • Jenner


Iii what is a virus

III. What is a virus?

  • A. Characteristics


B comparison to bacteria 1 overall

B. Comparison to bacteria1. overall

  • Bacteria Virus

  • Intracellular parasite (no) yes

  • Plasma membraneyes no

  • Binary fission yes no

  • Filterable no yes

  • Possess DNA & RNAyes no

  • ATP production yes no

  • Ribosomesyes no

  • Antibiotic sensitive yes no


Introduction to virology

  • 2. Growth comparison

  • 3. Size comparison

  • 4. Genome size comparison


Iv nucleocapsid morphology

IV. Nucleocapsid morphology


Introduction to virology

  • A. Helical

  • B. Polyhedral

  • C. Complex


V how viruses multiply 13 10

V. How viruses multiply (13.10)

  • 1. Basic strategy

    • Attachment

    • Penetration

    • Synthesis of viral proteins and nucleic acids

    • Maturation

    • Release


2 bacterial viruses fig 13 12

2. Bacterial viruses: Fig 13.12

  • Lytic vs lysogenic cycle


3 general animal virus multiplication

3. General Animal Virus Multiplication


A virus budding fig 13 20

a.Virus Budding: Fig 13.20


4 differences in lab culture of viruses

4. Differences in lab culture of viruses

  • a. bacteriophage

  • b. animal viruses


Vi differences in multiplication due to differences in genome organization

VI. Differences in multiplication due to differences in genome organization

  • A. Genome organization


B dna viruses life cycle fig 13 17

B. DNA Viruses: Life Cycle: Fig 13.17


C replication of rna viruses fig 13 17

C. Replication of RNA viruses: Fig 13.17


Vi classification schemes

VI. Classification schemes

  • A. Formal taxonomies

  • B. Baltimore Classification


C nucleic acid type baltimore classification

C. Nucleic acid type --> Baltimore classification

  • Class I

    • ds DNA

  • Class II

    • ssDNA (positive and negative)

  • Class III

    • dsRNA

  • Class IV

    • ssRNA (positive)


Introduction to virology

  • Class V

    • ssRNA (negative)

  • Class VI

    • ssRNA (positive, replication intermediate DNA)


1 class i dsdna viruses

1. Class I: dsDNA Viruses

  • Bacterial

    • Bacteriophage

  • Plant

    • Caulomoviridae


Introduction to virology

  • Human

    • Herpesviridae

    • Adenoviridae

    • Poxviridae

    • Papovaviridae

      • Papillomavirus

      • Polyomavirus

      • Vacuolating agent


Introduction to virology

  • Hepadnaviridae

    • After protein synthesis, DNA replicated through RNA intermediate


2 class ii ssdna viruses

2. Class II: ssDNA viruses

  • Bacteria

  • Plant

  • Animal


3 class iii dsrna viruses

3. Class III: dsRNA viruses

  • Reoviridae


4 class iv ss rna viruses

4. Class IV: ss (+) RNA viruses

  • Picornaviridae

  • Togaviridae

  • Flaviviridae

  • Coronaviridae

  • Calciviridae


5 class v ss rna viruses

5. Class V: ss (-) RNA viruses

  • Rhabdoviridae

  • Filoviridae

  • Paramyxoviridae

  • Orthomyxoviridae

  • Bunyaviridae

  • Deltaviridae

  • Arenaviridae


Retrovirus life cycle fig 13 19

Retrovirus Life Cycle: Fig 13.19


6 class vi ss viruses dsdna intermediate

6. Class VI: ss (+) viruses (dsDNA intermediate)

  • Retroviridae

    • Oncoviruses

    • Lentivirus


D review of replication strategies

D. Review of Replication Strategies


Vii effects of viral infection on cell

VII. Effects of Viral Infection on Cell


Viii oncogenic viruses

VIII. Oncogenic Viruses


Ix plant viruses

IX. Plant viruses

  • Morphologically similar to animal viruses

  • Enter through wounds or parasites

  • Some multiply in insects


X viroids

X. Viroids

  • Plant pathogens

    • infectious naked RNA

  • 20-25 identified so far

  • ss covalent circle


Xi prions

XI. Prions

  • A. Fig 13.21

  • B. PrPC vs PrPSc

    • Structural differences

    • Detergent solubility differences

    • Differences in susceptibility to protein degrading enzymes


Prion diseases of humans and animals

Prion diseases of humans and animals


  • Login