The role of viruses in the evolution of cyanobacteria

Cyanophages play an important role in the evolution of cyanobacteria. They control cyanobacterium abundance, population dynamics, and the structure of natural communities. Cyanophages are a global reservoir of genetic information. They act as vectors that transfer genes, endow cyanobacteria with novel properties, and affect the rate and direction of evolutionary processes. Lysogeny makes a significant contribution to the maintenance of the gene pool and ecological adaptation of cyanobacteria. The integration of many cyanobacterial genes into cyanophage genomes indicates that a genetic transfer occurs between hosts and phages. Such a gene transfer performs the driving functions in adaptive microevolution. Analysis of the molecular base of cyanophage–host interactions strongly supports the concept of the coevolution of cyanophages and cyanobacterial genomes.