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I found this site with the following lecture. As you see, it's a little old but most of the information is easy to understand because it's basic. There is one group of lectures on viruses and one on bacteria. Here's the summary from the first short lecture: The General Properties of Viruses
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MEDICAL MICROBIOLOGY FALL 2000
Dr. Tritz's Lectures
Professor and Chairman of the Department of Microbiology/Imunology
Kirksville College of Osteopathic Medicine
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1. Viruses contain either DNA or RNA as their genetic material, but not both. This nucleic acid usually has unique chemical and/or physical features which makes it distinguishable from human nucleic acid.
2. Viral nucleic acid is enclosed in a capsid made up of protein subunits called protomeres.
3. Some species of viruses have a membrane, the envelope, surrounding the capsid; other species do not have an envelope, i.e., they are naked. Enveloped viruses have glyco-protein spikes arising from their envelope. These spikes have enzymatic, absorptive, hemagglutinating and/or antigenic activity.
4. The morphology of a virus is determined by the arrangement of the protomeres. When protomeres aggregate into units of five or six (capsomeres) and then condense to form a geometric figure having 20 equal triangular faces and 12 apices, the virus is said to have icosahedral (cubic) morphology. When protomeres aggregate to form a capped tube, they are said to have helical morphology. Any other arrangement of the protomeres results in a complex morphology.
5. All viruses undergo a replication cycle in their human host cell consisting of adsorption, penetration, uncoating, nucleic acid replication, maturation and release stages.
6. During the viral replication cycle, an accumulation of mature viruses, incomplete viruses and viral parts occurs within the cell. This accumulation is the inclusion body. The size, shape, location and chemical properties of the inclusion body are used by the pathologist to diagnose viral infectious disease.
7. A virally-infected cell generally presents three signals that it is infected. The first is the production of double-stranded RNA, which induces interferon; the second is the expression of viral protein on the surface of the plasma membrane, thus causing activation of cytotoxic T-cells, natural killer cells and sometimes induction of antibody synthesis. The third is the formation of an inclusion body either within the cytoplasm or the nucleus or very rarely within both the cytoplasm and nucleus.
8. In general, all DNA-containing viruses replicate in the host cell nucleus. The exceptions to the rule are the poxviruses.
9. In general, all RNA-containing viruses replicate in the host cell cytoplasm. The exceptions to the rule are the retroviruses and the orthomyxoviruses.
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From one of the other lectures:
Antibodies to the ribonucleoprotein (RNP) are used to differentiate the three major types of influenza virus (A, B or C).
Each of these types may have antigenic variants;
these are designated A1, A2 ... or B1, B2, ... or C1, C2, ...
The hemagglutinin spikes are labelled H1, H2 ... for antigenic variants
The neuraminidase spikes are labelled N1, N2 ... for antigenic variants.
Present terminology of influenza virus type A strains designates the geographic area where the strain was first isolated, the year it was isolated and the antigenic composition of its hemagglutinin and neuraminidase. Thus, an H2 N1 strain of the influenza A1 virus first isolated in Missouri in 1984 would be designated: A1/Missouri/84 (H2N1)
1. There are 19 families of viruses that are defined by chemical type of nucleic acid, capsid symmetry, presence or absence of an envelope, number of capsomeres, physical type of nucleic acid and number of genes.
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MEDICAL MICROBIOLOGY FALL 2000
Dr. Tritz's Lectures
Professor and Chairman of the Department of Microbiology/Imunology
Kirksville College of Osteopathic Medicine
-----------------------------------------------------------------------
1. Viruses contain either DNA or RNA as their genetic material, but not both. This nucleic acid usually has unique chemical and/or physical features which makes it distinguishable from human nucleic acid.
2. Viral nucleic acid is enclosed in a capsid made up of protein subunits called protomeres.
3. Some species of viruses have a membrane, the envelope, surrounding the capsid; other species do not have an envelope, i.e., they are naked. Enveloped viruses have glyco-protein spikes arising from their envelope. These spikes have enzymatic, absorptive, hemagglutinating and/or antigenic activity.
4. The morphology of a virus is determined by the arrangement of the protomeres. When protomeres aggregate into units of five or six (capsomeres) and then condense to form a geometric figure having 20 equal triangular faces and 12 apices, the virus is said to have icosahedral (cubic) morphology. When protomeres aggregate to form a capped tube, they are said to have helical morphology. Any other arrangement of the protomeres results in a complex morphology.
5. All viruses undergo a replication cycle in their human host cell consisting of adsorption, penetration, uncoating, nucleic acid replication, maturation and release stages.
6. During the viral replication cycle, an accumulation of mature viruses, incomplete viruses and viral parts occurs within the cell. This accumulation is the inclusion body. The size, shape, location and chemical properties of the inclusion body are used by the pathologist to diagnose viral infectious disease.
7. A virally-infected cell generally presents three signals that it is infected. The first is the production of double-stranded RNA, which induces interferon; the second is the expression of viral protein on the surface of the plasma membrane, thus causing activation of cytotoxic T-cells, natural killer cells and sometimes induction of antibody synthesis. The third is the formation of an inclusion body either within the cytoplasm or the nucleus or very rarely within both the cytoplasm and nucleus.
8. In general, all DNA-containing viruses replicate in the host cell nucleus. The exceptions to the rule are the poxviruses.
9. In general, all RNA-containing viruses replicate in the host cell cytoplasm. The exceptions to the rule are the retroviruses and the orthomyxoviruses.
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From one of the other lectures:
Antibodies to the ribonucleoprotein (RNP) are used to differentiate the three major types of influenza virus (A, B or C).
Each of these types may have antigenic variants;
these are designated A1, A2 ... or B1, B2, ... or C1, C2, ...
The hemagglutinin spikes are labelled H1, H2 ... for antigenic variants
The neuraminidase spikes are labelled N1, N2 ... for antigenic variants.
Present terminology of influenza virus type A strains designates the geographic area where the strain was first isolated, the year it was isolated and the antigenic composition of its hemagglutinin and neuraminidase. Thus, an H2 N1 strain of the influenza A1 virus first isolated in Missouri in 1984 would be designated: A1/Missouri/84 (H2N1)
1. There are 19 families of viruses that are defined by chemical type of nucleic acid, capsid symmetry, presence or absence of an envelope, number of capsomeres, physical type of nucleic acid and number of genes.
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