I. Introduction
A. Living vs. nonliving
1. Viruses are acellular
2. Cannot self-replicate
B. Cultivation
1. Embryonated eggs
2. Cell monolayers
II. Structure of Viruses
A. Size
B. Capsids
1. Helical
2. Spherical: Icosahedron C. Nucleic Acids (genome)
1. DNA or RNA 2. ss or ds 3. Linear or circular 4. Size
a) most DNA
virus are dsDNA
b) most RNA
virus are ssRNA
RNA+ sense
RNA- sense
D. Envelopes E. Viral Enzymes F. Complex III. Viral Taxonomy
A. Host Range
B. Pathogenesis
C. Genome
D. Capsid
E. Presence of an envelope
F. Diameter of virion or nucleocapsid
IV. Bacteriophages
A. Classification
B. Replication of DNA Phages
1. One-step growth curve
2. Replication cycle
a) adsorption:
not random
b) injection
of phage DNA
c) synthesis
of phage nucleic acids and proteins
d) assembly
e) release
of phage
C. Lysogeny
V. Viruses of Eucaryotes
A. Replication of animal viruses
1. adsorption
2. penetration
3. uncoating
4. Replication
a) DNA viruses
b) RNA viruses
ssRNA+
ssRNA-
dsRNA
5. Synthesis of late proteins
6. Maturation/Assembly
7. Release of virions
a) naked
b) enveloped
B. Effects of viral infection on animal cells
1. Cytocidal infections
a) vacuoles
b) inclusion bodies
c) syncytia
d) lysis
2. lysogenic infections
a) latent
infections
b) transformation
C. Viruses and Cancer
1. Introduction
2. Examples
a) EBV
1) Burkitt's lymphoma
2) Evidence supporting EBV's role in cancer
3) mechanism of oncogenesis
b) HBV c) HPV d) HTLV-I/HTLV-II
VI. Viroids and Prions
A. Viroids and Virusoids
circular ssRNA
B. Prions
proteinaceous infectious particles