Prophage

=Prophage=

A **prophage** is a bacteriophage genome that has inserted itself, non-harmfully, into the bacterial chromosome during its lysogenic cycle. Upon detection of host cell damage, the prophage is excised from the genome and activated into the lytic (proliferative) cycle by a process called **induction**. Prophages are an important agent of //horizontal gene transfer// (transfer of DNA between individuals who are not parent and offspring), sometimes causing the spread of favourable genes among a bacterial population by the process of transduction. Prophages can modify the phenotype of their host, causing them to develop pathogenicity by synthesising new toxins or giving them immune resistance.