Prophage
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Prophage
A prophage is a temperate phage in its integrated status. Its genome can be integrated into the bacterial host chromosome or exists as an extrachromosomal plasmid.
Prophage
A temperate phage genome whose lytic functions are repressed and which replicates in synchrony with the bacterial chromosome.
prophage
A phage genome that has been inserted into a specific site on the bacterial chromosome.
prophase ...
What does the prophage do while it is a part of its host genome? It can express certain of its genes. For example, the gene that encodes diphtheria toxin is the property of a prophage in the diphtheria bacillus, not of the bacillus itself.
Genes within the prophage will be expressed providing their promoters are active.
Marker A gene which, on expression, allows easy identification of cells which carry it.
The lysogenic cycle occurs when the viral DNA is incorporated into the host DNA as a prophage. When the cell replicates the prophage is passed along as if it were host DNA.
When this occurs, the phage is latent, and the viral DNA is called a prophage. This prophage is replicated along with host DNA, so all subsequent cells produced by the infected but latent cell (lysogenic cells) carry a copy of the prophage.
The integrated phage, called a prophage, can confer new properties to the bacterium. For example, strains of Corynebacterium diptheriae, which have undergone lysogenic conversion, synthesize the toxin in diphtheria that damages human cells.
2. Regarding temperate phages, the process causing a prophage to become virulent.
3. In development, an interaction between two cell lineages to alter the developmental fate of one or both of them.
Lysogenic bacterium A bacterial cell whose chromosome contains a prophage.
Lytic bacteriophage A phage that replicates in its host and then lyses, or destroys, it.
 See also: Phage, Bacteria, Cell, Host, DNA
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