Introductory Material Flashcards
Give a very basic description of a virus.
An acellular microorganism that requires another host cell to replicate. Obligate intracellular parasite.
Give a very basic description of a virus.
An acellular microorganism that requires another host cell to replicate. Obligate intracellular parasite.
What is the basic structure of a virus?
Viruses have a genome, a capsid, and may have an envelope.
What is another name for a complete virus particle?
Virion
What size pore is required to make a viral sterilization filter?
10 nm
Define uncoating
Releasing a genome into a host cell
What do viruses neat from host cells in terms of machinery for replication?
Enzymes
Energy
Ribosomes
Molecular building blocks
How are the Baltimore classifications structured?
How each original genome type gets to mRNA.
What is the ICTV? What do they provide?
International Committee on the Taxonomy of Viruses - they provide official nomenclature
Define genetic economy.
When the genome’s size needs to be as small and efficient as possible so only what is necessary is incorporated and anything superfluous is left out to save space.
What is viral polyprotein processing?
A major strategy used to produce many functional viral proteins from a single open reading frame.
What are matrix proteins?
They bridge the nucleocapsid and the envelope.
What kind of capsids can viruses have?
Icosahedral and helical
Also binal and complex
How do capsids assemble?
Identical protein subunits assemble to make a protein shell which is symmetrical somehow.
Define a nucleocapsid
Capside + genome
What are viral core proteins?
Can help condense viral DNA with capsid
What are scaffold proteins?
Used to help assemble virions not retained in viral particle
What are matrix proteins?
They bridge the nucleocapsid and the envelope.
What is included in the budding out from a host cell?
cell membrane
nuclear envelope
organelles from the host cell
Describe transmembrane proteins.
3 functional domains: extracellular, transmembrane, and internal domains
Name a virus famous for creating multiple non-infectious particles.
Hep B particles
Describe the transmembrane domain of a transmembrane protein.
Anchor that holds a viral protein to the envelope.
Describe the internal domain of a transmembrane protein.
determines the protein selection for the envelope
What is a key concept in virology that is often overlooked?
Not all intact virions are infectious.
Define how you could define the state of a virion.
Defective and non-infectious? Immature? Mature and infectious? ISVP? VLP?
How many viral particles are created per virion?
The number of VLPs to virions is at least greater than 1.
Name at least three ways of counting viruses.
TCID50 Plaque assay HPLC Hemagglutination assay Q-PCR ELISA Flow cytometry Electron microscopy
What is considered to be the gold standard for virus counting? What problem can it encounter?
Electron microscopy. Does not allow for the potentially VLPs if they cannot be differentiated.
