Textbook Question
Compare and contrast production of viral proteins for dsDNA viruses and ssRNA+ viruses.
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Ch. 6 - Viruses and Prions
Norman-McKay2nd EditionMicrobiology: Basic and Clinical PrinciplesISBN: 9780137661619
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Table of contents
- Ch. 1 - Introduction to Microbiology22
- Ch. 2 - Biochemistry Basics19
- Ch. 3 - Introduction to Prokaryotic Cells17
- Ch. 4 - Introduction to Eukaryotic Cells16
- Ch. 5 - Genetics25
- Ch. 6 - Viruses and Prions12
- Ch. 7 - Fundamentals of Microbial Growth20
- Ch. 8 - Microbial Metabolism16
- Ch. 9 - Principles of Infectious Disease and Epidemiology11
- Ch. 10 - Host Microbe Interactions and Pathogenesis19
- Ch. 11 - Innate Immunity24
- Ch. 12 - Adaptive Immunity22
- Ch. 13 - Immune System Disorders15
- Ch. 14 - Biomedical Applications: Vaccines, Diagnostics, Therapeutics, and Molecular Method14
- Ch. 15 - Antimicrobial Drugs18
- Ch. 16 - Respiratory System Infections16
- Ch. 17 - Skin and Eye Infections19
- Ch. 18 - Nervous System Infections12
- Ch. 19 - Digestive System Infections20
- Ch. 20 - Urinary and Reproductive System Infections10
- Ch. 21 - Cardiovascular and Lymphatic Infections15
Norman-McKay2nd EditionMicrobiology: Basic and Clinical PrinciplesISBN: 9780137661619Not the one you use?Change textbook
Chapter 6, Problem 1
An RNA virus with an antisense or negative strand must have which of the following enzymes to replicate?
a. Reverse transcriptase
b. Host DNA polymerase
c. RNA-dependent RNA polymerase
d. Host RNA polymerase
Verified step by step guidance1
Understand the nature of the virus's genome: an RNA virus with an antisense (negative) strand means its RNA is complementary to the mRNA that can be translated into proteins.
Recall that for replication, the virus must produce a positive-sense RNA strand (mRNA) from its negative-sense RNA template.
Identify the enzyme responsible for synthesizing RNA from an RNA template, which is not typically found in host cells because host cells usually transcribe RNA from DNA, not RNA from RNA.
Recognize that this enzyme is called RNA-dependent RNA polymerase, which synthesizes a complementary RNA strand from an RNA template.
Conclude that the virus must carry or encode RNA-dependent RNA polymerase to replicate its genome and produce mRNA for protein synthesis.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Antisense (Negative) Strand RNA Virus
An antisense or negative strand RNA virus has a genome complementary to the mRNA needed for protein synthesis. It cannot be directly translated by host ribosomes and must first produce a positive-sense RNA strand to serve as mRNA for viral protein production.
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04:28
Replication of Double-Stranded RNA Viruses
RNA-dependent RNA Polymerase
RNA-dependent RNA polymerase is a viral enzyme that synthesizes RNA from an RNA template. Negative strand RNA viruses carry or encode this enzyme to transcribe their genome into a positive-sense RNA strand, enabling translation and replication.
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04:191) RNA Processing
Role of Host Enzymes in Viral Replication
Host DNA and RNA polymerases typically do not replicate RNA viruses directly, especially negative strand RNA viruses. These viruses rely on their own RNA-dependent RNA polymerase rather than host enzymes like DNA polymerase or RNA polymerase for genome replication.
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04:26Animal Viruses: 3. Synthesis & Replication
Related Practice
Textbook Question
Assume a new enveloped RNA virus is causing an epidemic. Which of the following may be useful to manage the disease? Select all that apply.
a. Injectable antibodies
b. Interferons
c. Antibiotics
d. Nucleoside analogs
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Textbook Question
A young mother who has hepatitis B is under your care. Your main concern is to prevent the spread of the virus from infected cells to healthy ones. You would recommend:
a. Acyclovir
b. Retrovir
c. Interferon
d. Valtrex
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