General Virology Flashcards
Naked Virus (Nucleocapsid) Composition
Viral genome + Capsid +/- Virus-Encoded Enzymes
Enveloped Virus Composition
Nucleocapsid (Viral genome + Capsid +/- Virus-Encoded Enzymes)
+
Host Membrane with Virus-Encoded Glycoproteins
Viral Genome types
DNA vs RNA
Double-stranded (ds) vs Single-stranded (ss)
Segmented vs Non-Segmented
Linear, Circular, or Helical
Single-stranded Genome types
Positive sense (+) RNA = Coding strand Negative sense (-) RNA = Template strand Ambisense (Genome contains both (+) & (-) strands
Capsid (Capsomere) shapes
Icosahedral
Helical
Complex
Virus-Encoded Glycoproteins functions
- Attachment to host cell & initiation of infection
- Viral antigens and stimulate antibody production
- Viral attachment proteins (VAPs) that bind to host cell structures like:
- Hemagglutinin (HA): binds erthrocytes
- Neuroaminidase (NA): Facilitate virion release from host cells
- Fusion proteins (F): facilitate fusion of virion and host cell
Naked DNA viruses
Parvoviridae
Adenoviridae
Papovaviridae
Naked RNA viruses
Astroviridae
Reoviridae
Picornaviridae
Caliciviridae
All DNA viruses are double-stranded EXCEPT
Parvoviridae (B-19): ss DNA
Hepadnavirus: incomplete ds DNA
All DNA viruses have Linear genome EXCEPT
Papovaviridae & Hepadnavirus (Circular)
All DNA viruses have Icosahedral capsid EXCEPT
Poxviruses (complex, bullet-shaped capsid)
All DNA viruses replicate in the nucleus EXCEPT
Poxviruses (in the cytoplasm cuz they carry their own DNA-dependent RNA polymerase)
All RNA viruses are single-stranded EXCEPT
Reoviruses (ds RNA)
All RNA viruses replicate in the cytoplasm EXCEPT
Orthomyxoviruses & Retroviruses (in the nucleus)
Viruses with segmented genomes
Bunyaviruses (3 segments)
Orthomyxoviruses (8 segments)
Arenaviruses (2 segments)
Reoviruses (10 or 11 segments)