Virology Fundamentals Flashcards
Baltimore group I classification
DS DNA viruses
Baltimore group II classification
SS (+/-) DNA viruses
Baltimore group III classification
DS RNA viruses
Baltimore group IV classification
SS (+) RNA viruses
Baltimore group V classification
SS (-) RNA viruses
Baltimore group VI classification
SS (+) RNA RT viruses
Baltimore group VII classification
pDS DNA RT viruses
Baltimore group I viral families (4)
Herpes, Papoma (polyoma and papiloma), Adeno, Pox
Baltimore group II Viral families (1)
Parvo
Adenovirus-associated virus
Baltimore group III Viral families (1)
Reoviridae (Rotavirus)
Double stranded RNA
Replication in cytoplasm
Baltimore group IV viral families (6)
Calico, Picorna, Hepe (Non-ENV)
Toga, Flavi, Corona (ENV)
Baltimore group V viral families (6)
Filo, Bunya, Arena (Lassa, Junin) Rhabdo, Orthomyxo, Paramyxo (Measles, mumps, PIV)
Negative sense RNA single strand
Baltimore group VI viral families (1)
Retro
Baltimore group VII viral families (1)
Hepadna
Name 3 enveloped DNA viral families
Herpes, Pox, hepadna
Name 3 non enveloped DNA viral families
Adeno, Papoma, Parvo.
Which viral family has a complex capsid
Pox
Name 3 viral families with circular DNA
Papilloma, polyoma and Hepadna
Papilloma and polyoma are non enveloped
Hepadna (hbv is partially double stranded, enveloped)
Which Baltimore groups contain DNA viruses
I, II, VII
Which Baltimore groups contain RNA viruses
III, IV, V, VI
Do any DNA viruses have helical capsids?
No, most are icosahedral, Pox is complex.
This DNA virus contains repeated sequences and has a hairpin structure at one end
Parvovirus
This linear dsDNA virus has two unique sequences flanked by reiterated sequences
Herpes
This DS-DNA virus contains covalently closed circular DNA in a superhelix
Papoviridae
(includes papilloma and polyomavirus
60nm
Icosohedral
No envelope
This linear DS-DNA virus has inverted terminal repeats and a covalently bound protein
Adeno
This linear DS-DNA virus has and x-linled genome, both ends are covalently closed and it contains inverted terminal repeats
Pox
Poxviruses replicate in discrete factories in the cytoplasm. Their double-stranded DNA genomes, which encode proteins for DNA replication, are linked at the ends, forming one continuous polynucleotide chain
These RNA Viruses have helical capsids (7)
Corona (IV)
Rhabdo, Filo, Bunya, Arena, Orthomyxo, Paramyxo (V)
These RNA viruses have Icosahedral capsids (7)
Reo (III)
Flavi, Toga, Hepe, Calico, Picorna, (IV)
Retro (VI)
Name 5 non enveloped RNA viral families
(CHAPS is acronym fir the group 4)
Reo (III)
Calico, Picorna, Hepe (IV), Astro
Name 10 enveloped RNA families
Toga, Flavi, Corona (IV)
Rhabdo, Filo, Bunya, Arena, Orthomyxo, Paramyxo (V)
Retro (VI)
Are RNA viral genomes typically linear or circular?
Linear, no circular.
Virion polymerase is required for replication is some viruses (mostly those with cytoplasmic replication cycles). Name 10 viral families with virion polymerase.
Pox (I)
Reo (III)
Rhabdo, Filo, Bunya, Arena, Orthomyxo, Paramyxo (V)
Retro (VI)
Hepadna (VII)
Viral family with 10-18 segmented genome.
Reo
Most RNA viruses use 3′ end cleavage and polyadenylation (CPA) to aid the exit from the nucleus. Which RNA viral family doesn’t?
Flavi (IV)
Except for a few of the tick-borne flaviviruses the 3′-end is not polyadenylated—instead there is a 3′-hairpin loop
These 2 RNA virus families have VPg linked genomes and proteins attached at the 5’ end.
Calico and Picorna (IV)
This RNA virus family is tri-segmented with ambisense coding
Bunya (V)
This RNA virus family is bi-segmented with ambisense coding
Arena
This RNA virus family is has 7-8 segments and sequesters host 3’ cap from host pre-mRNA
Orthomyxo
This viral family had a diploid genome (contains 2 copies)
Retro
Which virus replicates via a double rolling RNA syntheseis
HDV
Encodes a single structural protein Small protein for viral replication and Large protein (promotes packaging of mature virions)
C-terminus: facilitated by an isoprenoid prosthetic side chain covalently bound to its C-terminus
With regards to HIV, what do the following Env, Pol, gag
Env: encodes envelope proteins for cell entry and tropism
Pol: encodes reverse transcriptase and integrase
Gag: viral structural proteins
Retroviruses are a family of viruses, the common feature of which is the use of an enzyme called reverse transcriptase to convert viral RNA into proviral DNA within infected/transduced host cells. Another viral enzyme, integrase, then integrates the proviral DNA into the host cell’s genome. Host cell molecular machinery then expresses this proviral DNA to produce new viruses that can infect other cells
Enterovirus D 68 is easily detectable is poop. T/F?
False
D68 is acid labile, unlike other enteroviruses is rarely detected in stool
List 4 families of viruses that cause VHF
Arenaviruses
Filoviruses
Bunyavirus
Flavivirus
What baltimore groups is adeno virus associated virus
It is a ssDNA, group 2, parvovirus
What baltimore group is torque tenovirus
ssDNA , group 2
What virus family is adeno-associated virus
Parvoviridae
Baltimore Group 2: others in group are bocapovirus, parvo
What is RNase H
a ubiquitous enzyme that degrades the RNA strand of an RNA–DNA duplex
Functions of reverse transcriptase
RT is a multifunctional enzyme possessing each of RNA and DNA polymerase activities as well as an RNase H activity and is responsible for converting the single-stranded viral RNA genome into dsDNA. which becomes integrated into host cell DNA
RNase H degrades RNA
Inhibited by NNRTI and NRTI and NRTTI
NRTI: act as competitive inhibitors and cause chain termination of the growing viral DNA chain (need phosphorylation step)
NNRTI: non-competitive
binding of the NNRTI to the reverse transcriptase and the creation of a hydrophobic pocket proximal to the active site. This pocket creates a new spatial configuration of the substrate-binding site to reduce the overall polymerase activity. By creating a different configuration, DNA synthesis becomes slowed overall. Because of the non-competitive inhibitor action of NNRTI, it is not effective against HIV-2 reverse transcriptase
Receptor for HSV-1
Heparin Sulphate
Heparan sulfate interacts with HSV-1 envelope glycoproteins gB and gC during the initial attachment step during HSV-1 entry. Present on most cells
Replication by host RNA polymerase II
Latency in nerve ganglia
Which virus uses GM1
ganglioside receptor
SV40
DC-SIGN receptor
HHv8
CAR
Integrin
avß3 or ayßs receptors
Adenovirus
CD155 receptor
poliovirus
SLAM CD150
Measles
Which receptor P- antigen
Parvo B19
Erthrocyte progenitor, endothelial and fetal myocytes, placental trophoblasts
What is syncytia
Syncytia result from the fusion of an infected cell with neighboring cells, leading to the formation of multinucleated, enlarged cells. This process is triggered by the surface expression ofviral fusion proteinsthat are fusogenic directly at the host cell membrane.
Syncytia can only arise with viruses that are able to fuse directly at the cell surface without requiring endocytosis.
