Chapter 1 Flashcards
(17 cards)
What are Viruses ?
submicroscopic, obligate intracellular parasites
what is the largest virus particle known?
Pithovirus = 1500 nm
What is the largest virus genome?
Pandoravirus = 2.47 Mbp
Four times as big as the smallest bacterial genome
What are the three unique features of viruses?
1) Virus particles are produced from the assembly of preformed components, other biological agents grow from an increase in the integrated sum of their components and reproduce by division.
2) Virus particles (virions) do not grow or divide.
3) Viruses lack the genetic information that encodes tools necessary for the generation of metabolic energy or protein synthesis (ribosomes).
When was the first time viral infection was documented?
3700bc - Parylictic poliomyelitis
What vaccine did Edward Jenner make and when?
Smallpox vaccination, 1796
What did Louis Pasteur do?
Made a rabbies vaccine from rabbits
What did Robert Koch and Louis Pasteur do?
Germ theory of disease 1880s
Who discovered filterable particles?
1892: Dimitri Iwanowski
What did Walter Reed do?
Discovered the yellow fever virus was spread by mosquito’s
Why do animal host studies still have to be used ?
1) some viruses cannot be effectively studied in vitro (hep B)
2) To study the pathogenesis of virus infections (e.g. HIV and SIV)
3) To test vaccine safety (e.g. oral poliovirus vaccine)
What are transgenic animals?
animals which which carry the genes of other organisms.
Why are transgenics useful ?
Transgenics are useful for understanding the pathogenesis of viruses, prions.
Describe different cell culture methods and how these are carried out- not on answer flash card.
1949: John Enders propagates poliovirus in human cells
1950s and 1960s: identification and isolation of many viruses
1952: Renato Dulbecco - plaque assay
What did George Hurst discover in 1941?
haemagglutination of red blood cells by influenza virus.
Name some improved detection methods for virus detection.
Radioimmunoassays
Immunofluorescence (direct detection of virus antigens in infected cells or tissue)
Enzyme-linked immunosorbent assays (ELISAs)
Radioimmune precipitation
Western blot assays
What is virus metagenomics?
Analysis of all the virus genomes in a particular environment (virome) rather than the genome of a single organism
