Stanley isolated TMV in 1930's Hershey & Chase in 1952- demonstrated nucleic
acids carried genetic info into cells while protein
remained outside -molecular biology- chemical & physical
basis of biology Life defined: Viruses defined: *dormant phase- extracellular, not active Virology defined: (recent): includes genetic engineering c "benign"
viruses; biowarfare vs. insects Sx of viral infection: Taxonomy:
History of Virology:Jenner in late 1700's- developed smallpox
vaccine
Pasteur in 1880's- developed attenuated rabies vaccine
Bawden & Pirie in 40's- demo of P in TMV, therefore
nucleic acid also present, not just pure protein
-molecular virology- biochem nature of virusesdynamic integrated state of biochem &
physical interactions
reproduce only in living cells
contain RNA or DNA vs. organisms which require both
not true life- no energy production
*vegetative phase- intracellular, complex
interaction c hostvirus transmission; epidemiology & ecology;
pathology & Rx
eradication- only one success: smallpox
can be not detectable to severe Dz to death
systemic or local lesiondifferences between bacteria, plants, animals in
nomenclature
ICTV: International Committee on Taxonomy of Viruses
working to standardize nomenclature &
link specialized collections worldwide
Next week:In-depth view of structures- read Wagner, ch. 2
& 5
Methods of studying viruses- browse Wagner, part 3
Updated 1/25/04 by thatcher@sonoma.edu