A prophage is a bacteriophage (often shortened to "phage") genome inserted and integrated into the circular bacterial DNA chromosome or exists as an extrachromosomal plasmid. This is a latent form of a phage, in which the viral genes are present in the bacterium without causing disruption of the bacterial cell.

What is the difference between a phage and a virus?

Bacteriophages inject DNA into the host cell, whereas animal viruses enter by endocytosis or membrane fusion. Animal viruses can undergo latency, similar to lysogeny for a bacteriophage.

Are there phages for viruses?

We have bacteria that live on us, and bacteria have bacterial viruses that live on them (Figure 1). These viruses are called bacteriophages (or phages). Viruses differ from bacteria in that they are not made of cells, but instead consist of a piece of DNA (or RNA) packed within a protein coat.