Transcript Viral Structure & Types - Narragansett Pier School

STRUCTURE
Three components:
-
Capsid (capsomeres)
-
Genome
-
Envelope (some have this)
-
Viral Envelope
-viral glycoproteins
- derived from host membrane
(3-5 average, - over 100 expressed proteins)
Mimivirus! – size of small becteria
- Bring questions as to evolutionary history
TYPES OF VIRUSES
-
Capsid structure
- rod-shaped
-polyhedral
-or more complex
Host Range
Bacteriophage – viruses that infect bacteria
I’D LIKE TO INFECT YOU WITH MY DNA ;)
;)
Viral Reproduction
TWO MECHANISMS OF REPLICATION BY PHAGES:
LYTIC AND LYSOGENIC CYCLES
Animation: Phage T4 Lytic Cycle
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.
Animation: Phage Lambda Lysogenic and Lytic Cycles
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.
EVOLUTION
Replication occurs in host cell
Uses host cell’s organelles to synthesis progeny viruses
FIGURE 19.8
Glycoprotein
Viral envelope
HIV
Capsid
Reverse
transcriptase HIV
RNA (two
identical
strands)
Membrane
of white
blood cell
HOST
CELL
Reverse
transcriptase
Viral RNA
RNA-DNA
hybrid
0.25 m
DNA
HIV entering a cell
NUCLEUS
Provirus
Chromosomal
DNA
RNA genome
for the
next viral
generation
mRNA
New virus
New HIV leaving a cell
K A R A HEAT HERTO N , JA K E RO ST, G R IFFIN S C HRO ET ER
VIRAL DISEASE IN ANIMALS & PLANTS
Symptoms
Severity of the virus
Vaccine
Treatment
EMERGING VIRUSES
Epidemic
Pandemic
3 factors
 1. mutations
 2. spread from humans
 3. spread from animals
VIROIDS AND PRIONS
I’D LIKE TO INFECT YOU WITH MY DNA ;)
;)
Viral Reproduction
TWO MECHANISMS OF REPLICATION BY PHAGES:
LYTIC AND LYSOGENIC CYCLES
Animation: Phage T4 Lytic Cycle
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.
Animation: Phage Lambda Lysogenic and Lytic Cycles
Right-click slide / select “Play”
© 2011 Pearson Education, Inc.
EVOLUTION
Replication occurs in host cell
Uses host cell’s organelles to synthesis progeny viruses
FIGURE 19.8
Glycoprotein
Viral envelope
HIV
Capsid
Reverse
transcriptase HIV
RNA (two
identical
strands)
Membrane
of white
blood cell
HOST
CELL
Reverse
transcriptase
Viral RNA
RNA-DNA
hybrid
0.25 m
DNA
HIV entering a cell
NUCLEUS
Provirus
Chromosomal
DNA
RNA genome
for the
next viral
generation
mRNA
New virus
New HIV leaving a cell
K A R A HEAT HERTO N , JA K E RO ST, G R IFFIN S C HRO ET ER
VIRAL DISEASE IN ANIMALS & PLANTS
Symptoms
Severity of the virus
Vaccine
Treatment
EMERGING VIRUSES
Epidemic
Pandemic
3 factors
 1. mutations
 2. spread from humans
 3. spread from animals
VIROIDS AND PRIONS