Phage Conversion

Phage conversion

Phage conversion (Latin conversio - change, transformation; synonym lysogenic conversion) is a process in which a bacteriophage integrated into a bacterial chromosome changes the phenotype of the host cell without affecting its genotype.

After infecting a bacterium, the phage can either kill the cell by multiplying within it (lysogenic cycle) or integrate into the bacterial genome, transferring the cell to a state of lysogeny. In this case, phage DNA can be integrated into certain parts of the chromosome or plasmid of the host cell. The embedded phage DNA is called a provirus.

The presence of a provirus in the bacterial genome leads to the expression of phage genes, which can change the properties of the cell. For example, phages often transfer genes for toxins, enzymes, or virulence factors, making the bacterium more pathogenic. Thus, phage conversion is one of the mechanisms of horizontal gene transfer that increases the adaptability of bacteria.

Phage conversion is the process by which phage viruses enter a bacterial cell and capture its genetic material. This occurs thanks to specific viral proteins (fagin), which recognize certain sections of bacterial DNA and can penetrate into the cell. As a result, phage replication begins, which leads to the formation of new copies of the virus inside the bacterium. After reproduction is completed, the phages leave the cell, leaving behind the altered genetic material of the bacteria. This process can lead to various changes in the genetic material of bacteria, such as changes in DNA structure, inclusion or exclusion of genes, etc. Phage conversion can be used in genetic research to obtain mutations in various breeds of plants and animals, as well as to create new strains of bacteria with desired properties. In addition, phage conversion can be used industrially to produce various biologically active substances, such as antibiotics, enzymes and other useful substances. However, it must be remembered that the use of virions can lead to epidemics, so this technology must be controlled and safe.