exam 3 ch 14 pt 1 Flashcards
what year was cholera present in the US
1800s
how many Americans died form cholera
150,000
Nepal Cholera closest to
Haiti strain
parsimony informative SNPs
infectious disease that affects an unusually large proportion of the population within a
specific community
epidemic
An epidemic of infectious disease that has spread through human populations across a large
region, multiple continents, or even worldwide
pandemic
A protein shell enclosing a virus’s genetic material
Capsid
Protective coating made of lipids proteins, and carbohydrates
Viral Envelope:
spike-like projections on the envelopes surface that help the virus recognize and
attach to host cells.
Glycoproteins
Viruses can have (ssDNA) single strandedDNA (dsDNA) doubled strandedDNA, (ssRNA) single stranded RNA (dsRNA) or even double stranded RNA
nucleic acids
What are the main components of a virus?
capsid
viral envelope
nucleic acids
What kind of nucleic acids can make up a viral genome?
ssDNA
daDNA
ssRNA
dsRNA
a contagious enveloped 8 stranded RNA virus which causes respiratory illness that can result in death.
influenza
Virus surface proteins
Hemagglutinin and Neuraminidase
Molecules that can be recognized by the immune system and are capable of triggering an
immune response
antigens
Hemagglutinin and Neuraminidase are?
antigens
When a virus undergoes a gradual change in genetic makeup, but is similar to parent virus
antigenic drift
When a virus undergoes a sudden change in genetic makeup, creating a new strain
antigenic shift
The influenza genome encodes ?
the viral RNA polymerase PB2
1918 pandemic was caused by the ______________of a fully avian virus to a form that could infect humans efficiently
antigenic drift
Mutations in the viral RNA polymerase PB2, particularly in what mutation?
E627K mutation.
Influenza viruses ________________ caused the Asian Flu pandemic of 1957 & originated from an avian
influenza A virus
antigenic shift
first 3 pandemics
drift, shift, shift
The most recent 2009 H1N1 outbreak was a result of _________________ and reassortment between human,
avian, and swine viruses
antigenic shift
indicates the progenitor of the 2009 epidemic originated in
pigs & The polymerase genes, plus HA, NP and NS, emerged from a triple-reassortant virus circulating in North American swine.
Parsimonious phylogenic reconstruction
Enveloped single-stranded RNA (ssRNA) viruses
Coronaviruses
Lethal coronaviruses have ____________________________ that allow them to bind and penetrate human cells more effectively
spike & nucleocapsid proteins
The study of the past through the examination of preserved genetic material from the remains of ancient organisms
Paleogenetics
In human evolution, selection has led to the ________ of gene variants encoding virus-interacting
proteins at ___ the rate observed for other classes of genes
fixation, 3X
Selection that drives a beneficial variant to substantial frequencies in a population
Selective Sweep
-Confirmed interactions = green circle
-Mutations lie near regulatory variants in SARS-CoV-2-affected tissues (lungs)
Human virus-interacting proteins (VIP) / SARS-CoV-2 interaction analysis
kind of graph based method, to infer the timing.
Ancestral recombination graph (ARG)
Severe acute respiratory syndrome (SARS)-associated coronavirus
(SARS-CoV)
Middle East Respiratory Syndrome (MERS) coronavirus
(MERS-CoV)
A mild to severe respiratory illness that is caused by SARS-CoV-2
Coronavirus disease 2019 (COVID-19):
A single-stranded RNA coronavirus
transmitted through liquid droplets that evolved from a bat coronavirus
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2):
SARS-CoV-2 strains mainly vary in ?
the RNA polymerase and Spike proteins
RNA-dependent RNA polymerase
(RNA replicase)
Spike protein binds host ?
angiotensin converting enzyme 2 (ACE2) receptor
Cleaves the SARS-CoV-2 S2 spike protein which allows viral entry into cells
transmembrane protease serine 2 (TMPRSS2) & furin protease
An enzyme that cuts other proteins
Protease
the cleavage of the spike protein determines?
viral infectivity and host range
a membrane protein that spans the entirety of the cell membrane
transmembrane protein
SARS-CoV-2 strains mainly vary in the?
RNA polymerase and Spike proteins
Infection that is constantly maintained at a baseline level in a geographic area
endemic
what is the closest relative of SARS-CoV-2
NRR 4 Sequence from the Rhinolophus bats
SARS-CoV-2 likely had a _______________________, where a part of the virus RNA is inserted into a different copy of the virus RNA by the human cell’s enzymes indicating _____________________
recombination event
Antigenic Shift
SARS-CoV-2 evolution inserted a _______________ into the spike protein
furin cleavage site
Mutation N501Y, a change from asparagine (N) to tyrosine (Y) in
amino-acid position 501 of the spike protein
Alpha variant (B.1.1.7)
Alpha variant (B.1.1.7) was estimated to be _________ more transmissible
40–80%
Has the N501Y mutation, but gained 2 new mutations E484K and K417Nof the spike protein, that are not
found in Alpha variant
Beta variant (B.1.1.7):
Mutation at position 452, a leucine-to-arginine substitution L452R of the spike protein .
-Created stronger affinity of the spike protein for the ACE2 receptor
delta variant (B.1.1.7)
also decreases recognition capability of the immune system
delta variant
Omicron did not evolve from any other variant, but instead diverged on a distinct track, perhaps in 2020
Omicron (B.1.1.529):
