Related Experiment Video
Updated: Aug 7, 2026
09:25
Rapid, Seamless Generation of Recombinant Poxviruses using Host Range and Visual Selection
Published on: May 24, 2020
Characterization of deoxyribonucleases induced by poxviruses
C Jungwirth1, J Launer, G Dombrowski
1Institute for Virology, University of Würzburg, Würzburg, Germany.
Journal of Virology
|December 1, 1969
Summary
Poxviruses induce deoxyribonuclease (DNAase) activity in host cells. These viral DNAases, distinct from cellular enzymes, can be separated and characterized by their unique properties.
Area of Science:
- Virology
- Molecular Biology
- Enzymology
Background:
- Poxviruses are known to replicate within host cells.
- Cellular deoxyribonuclease (DNAase) activity is crucial for DNA metabolism.
- Viral infections can alter host cell enzymatic functions.
Purpose of the Study:
- To investigate the induction of deoxyribonuclease (DNAase) activity in poxvirus-infected cells.
- To characterize the properties of viral-induced DNAases and compare them to cellular DNAases.
- To differentiate between DNAases induced by different poxviruses.
Main Methods:
- Assaying deoxyribonuclease (DNAase) activity at alkaline pH using native and denatured deoxyribonucleic acid (DNA) as substrates.
- Employing diethylaminoethyl cellulose chromatography to separate enzymes from infected and normal HeLa cells.
- Characterizing the enzymatic reaction properties of the isolated DNAases.
Main Results:
- Poxvirus infection leads to increased deoxyribonuclease (DNAase) activity.
- The induced viral DNAases can be chromatographically separated from normal cellular DNAase.
- Cowpoxvirus and vaccinia virus WR induce distinct DNAases with different chromatographic properties.
- The enzymatic properties of the two induced DNAases were further elucidated.
Conclusions:
- Poxviruses induce specific deoxyribonuclease (DNAase) enzymes in infected cells.
- These viral DNAases are biochemically distinct from host cell DNAases.
- The characterization of these viral enzymes provides insights into poxvirus replication mechanisms.
Related Concept Videos
01:24Smallpox
Smallpox is a severe contagious disease caused by the Variola major virus, a double-stranded DNA member of the Poxviridae family.Variola major transmission occurs primarily via inhalation of virus-laden droplets or direct contact with infectious scabs. The incubation period averages approximately seven days, although it may range from 7 to 17 days depending on the inoculum and host factors.Clinically, the prodromal phase is marked by an abrupt onset of high fever, malaise, headache, and myalgia.
02:47Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
01:29Viruses with RNA Genomes
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
01:25Inhibitors Of Virion Release
Viral replication and dissemination rely on efficient mechanisms for host cell entry, genome replication, assembly, and release. Influenza viruses, such as types A and B, are negative-sense single-stranded RNA viruses with a segmented genome, that depend on two critical surface glycoproteins to carry out these processes: hemagglutinin (HA) and neuraminidase (NA). HA initiates infection by binding to sialic acid residues on the surface of host epithelial cells, facilitating receptor-mediated...
01:19Inhibitors of Virion Maturation and Assembly
As part of their replication cycle, certain viruses synthesize long precursor proteins called polyproteins within infected host cells. In human immunodeficiency virus (HIV), two major polyproteins are produced: Gag and Gag-Pol. The Gag polyprotein supplies the structural components of the virus, while Gag-Pol includes essential viral enzymes such as reverse transcriptase, integrase, and protease. After synthesis, these polyproteins move to the host cell membrane, where they assemble into an...
02:10Translesion DNA Polymerases
Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...