Chapter 9- Microbiology
Viral genomes can either be _____ or _____ genomes
DNA or RNA
delayed early: encodes _____ proteins
DNA replication
Bacteriophage T7... infects _____ Virion has an _____ head and a very ___ tail
E Coli head short
Negative Strand RNA Animal viruses Influenza... breaks down sialic acid component of host cytoplasmic membrane
Neuraminidase
Positive strand RNA virus
Phage MS2
Bacteriophage Mu is a
double stranded DNA bacteriophage
Bacteriophage T7 is a ______ Bacteriophage DNA replication employs T7 _____ and involves ______ and the formation of _____
dsDNA DNA polymerase terminal repeats concatemers
Viruses of Archaea... Most viruses that infect Archaea resemble those that infect _____ Only _______ viruses have been identified so far
enteric bacteria double stranded DNA
product is processed into 2 distinct envelope proteins
env
encodes several small viral structural proteins
gag
Retroviruses... gene expression and protein processing are complex ALL retroviruses have 3 genes _____, ________, ______
gag pol env
Negative Strand RNA Animal viruses Influenza... causes clumping of red blood cells
hemagglutinin
Hepadnaviruses... virions small, irregular shaped particles include ________ viral replication occurs through an ______ intermediate Unusual genomes: _____ and only partially ________
hepatitis B RNA tiny double stranded
Bacteriophage M13 viral infection slows _____ growth
host
Bacteriophage T7... Genome always enters _____ cell in ____ oreinetation Order of genes on the T7 chromosome influences ______ of virus replication
host same regulation
Rhabdoviruses... RNA of rhabdoviruses is transcribed in the _______ into 2 distinct classes
host cytoplasm
Herpesviruses... ______ group of viruses that cause diseases in humans and animals Able to remain _____ for extended periods of time An important group causes _____ forms of cancer example: Epstein-BArr virus
largest latent clinical
Bacteriophage M13 can be released without ____ host via a process called ______
lysing budding
Negative strand RNA Animal viruses... Negative strand RNAs are complementary to the _______ They are copied into mRNA by an _____ present in the virion Only those that infect _____ are known
mRNA enzyme Eukarya
Reoviruses... virions contain virus encoded enzymes necessary synthesize _____ and the new ______ genomes
mRNA RNA
Bacteriophage Mu... known as the _____ phage induces mutations in ____ genome Useful in ______ ______ phage
mutator host bacterial genetics temperate
Replication of positive strand RNA viruses requires a _______ intermediate from which new positive strands are synthesized
negative strand RNA
Adenoviruses.... DNA replicates in the _______ replication requires protein _______ and avoids synthesis of a ______ strand
nucleus primers lagging
Some polyoaviruses cause cancer... In _____ host cells, virus infection results in the formation of new virions and the lysis of host cells
permissive
Phage MS2... an example of a bacterial RNA virus that infects E Coli by attaching to _____ Possesses a _____ genome that is directly translated by a combination of _____ and ______ enzymes possesses _____ genes
pilus small host viral overlapping
Some bacteriophages contain ssDNA genomes of the _____ configuration
plus
is translated into a large polyprotein
pol
Positive strand RNA viruses also include
poliovirus
Some DNA animal viruses can induce cancer: these include
polymavirus SV40 Herpesviruses
among the most complex and largest animal viruses known ________ DNA replicate in the ______
pox viruses cytoplasm
Uniquely replicating DNA animal viruses... Double stranded DNA animal viruses that have unusual replication strategies include
pox viruses and adenoviurses
infectious proteins whose extracellular form contains no nucleic acids
prions
Negative strand RNA Animal viruses... Rhabdoviruses Include viruses that cause: ____ in animals and humans, ___ in cattle, pigs, and horses _____ viruses Virion is ___ shaped
rabies vesicular stomatitis enveloped bullet
Herpesviruses.. infection follows attachment of virions to specific cell _____ 3 classes of mRNA produced ______
receptors immediate early delayed early late
Poliovirus... host RNA and protein synthesis are inhibited when poliovirus _______ begins
replication
Enveloped virions that contain 2 copies of the RNA genome
retrovirus
Viruses that use reverse transcriptase
retroviruses (RNA viruses) and hepadnaviruses (DNA viruses)
Retroviruses.. virions contains several enzymes Includes _________ use to make DNA copy of genome
reverse transcriptase
Replication in Bacteriophage OX174 occurs via
rolling circle replication
Negative Strand RNA Animal viruses Influenza... Enveloped, pleomorphic virus ______ genome _______ proteins interact with host cell surface
segmented surface
poliovirus... ____ virus Viral RNA is translated ______, producing a single long giant protein called _______, that undergoes ______ to generate 20 smaller proteins necessary for _______ and virus ______
small directly polyprotein self cleavage nucleic acid replication assembly
Bacteriophage OX174 has very ____ genome with ____ genes
small overlapping
Viroids are the _________ known pathogens cause a number of important plant _______ small, circular, ssRNA molecules do not encode ______, completely dependent on ________
smallest diseases proteins host encoded enzymes
Rhabdoviruses 2 distinct classes include: 1. series of mRNAs encoding the _____ genes of virus 2. ________ RNA that is a copy of the complete viral genome
structural positive strand
Late encodes _____ of the virus particle
structural proteins
Transcription of the genome is preceded by ______ of a ______
synthesis of a complementary strand of DNA
Viruses may have played a role in transition from
RNA to DNA
Double stranded RNA viruses.... Non enveloped nucleocapsid with a double shell of icosahedral symmetry
Reoviruses
Reoviruses... genomes segmented into _____ molecules of _______ double stranded RNA Replication occurs exclusively in cytoplasm within the ______
10-12 linear nucleocapsid
3 classes of mRNA are produced... Immediate early: encodes _____ proteins
5 regulaotry
Major group of icosahedral, linear, double stranded DNA viruses is _____ cause mild ______ in humans
Adenoviruses respiratory infections
structure of neuraminidiase and hemagglutinin proteins are subtly altered
Antigenic drift
Model filamentous bacteriophage
Bacteriophage M13
Bacteriophage Mu... Invertible ____ region of genome determines host range Genomes is integrated into the host chromosomes via _____
G Transposase
Some polyoaviruses cause cancer... In _____ host cells, the virus DNA becomes integrated into host DNA (analogous to a prophage), genetically altering cells in the process
Her
Polyomavirus SV40: induces tumors in ____ ______ vision with an icosahedral head No ____ in the virion, replicate in ______ nucleus
animal Nonenveloped enzymes host
prions... known to cause disease in ____ host cell contains gene _____ that encodes native form of prion protein that is found in healthy animals prions _______ results in neurological symptoms of disease (resistance to protease, insolubility, and aggregation)
animals PrnP misfolding
Portion of the RNA genome from two genetically distinct strains of virus infecting the same cell are reassorted Generates virions that express a unique set of surface proteins
antigenic shift
Viruses may have arisen after _____, remnants of cells that replicate with the help of a ______ cell
cells live
What is the smalls viral genome size and the largest viral genome size and the names of each?
circovirus: 1.75 kbp megavirus: 1.25 mbp
Viral genomes shape some are _____, but most are _____
circular linear
Polyomavirus SV40 DNA is _______ Small genome, has _____ genes
circular overlapping
Bacteriophage OX174 contains a ______ genome inside an icosahedral virion
circular single-stranded DNA
Bacteriophage M13 is used as a _____ and DNA-sequencing vector in _____
cloning genetic engineering
Negative Strand RNA Animal viruses... Processes that help influenza elude the host _____
immune system
Coronaviruses.. _____ viruses Causes ______, including ____, in humans and animals Virions are ______, contain club shaped glycoprotein ____ on their surfaces, produces _____ mRNA
larger respiratory infections SARS enveloped spikes monocistronic
Bacteriophage Mu... in both lytic and lysogenic pathways, the genome is replicated as part of a ____ molecule Lysogenic requires sufficient amounts of a _______ to prevent transcription of integrated Mu DNA Genome is packaged into the vision with _______ of host DNA at either end
larger DNA molecule repressor protein short 5bp sequences
Bacteriophage Mu... replicates by _____ Large virus with a icosahedral head, ____ tail, and ___ tail fibers
transposition helical six
infectious RNA molecules that lack a protein coat
viriods