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Some Virus Resources on the Web:

ViralZone: http://viralzone.expasy.org/

International Committee on the Taxonomy of Viruses:

http://www.ictvdb.org/

Viral origins: http://www.mcb.uct.ac.za/tutorial/virorig.html

6 & 9.6 - Viruses (for more details on human pathogens see Ch 24 & 25)

A virion

Relative size

Surprise! giant Mimivirus 500 nm (or 0.5 um)

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Virus ID

*Signs & Symptoms

DNA eg: PCR

*Serology

TEM

Light & Fluorescent Microscopy

Cytopathic effects: make hosts cells strange

Classification: Type of Nucleic Acid (see also T6.2):

DNA or RNA? If RNA, which kind?

Retroviridae only

From: Clinical Microbiology Made Ridiculously Simple

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Classification: What capsid morphology?

polyhedral

eg: Adenovirus

Classification: What capsid morphology?

helical

eg: tobacco mosaic virus

complex eg: T4 bacteriophage

Classification: envelope?

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Phage plaques on bacterial lawn

Phage culturing (have to grow with host bacteria)

Phage added

close-up (TEM)

No phage

Viral Reproduction

eg: lytic Bacteriophage (like T4)

Viral Reproduction

eg: lysogenic Bacteriophage (such as lambda)

becomes a prophage/ provirus for a time

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Animal virus differences:

Entry

fusion

endocytosis

Other animal virus differences

envelope sometimes

carry along?

euk. cell compartments

effects