When a virus is not a parasite: the beneficial effects of prophages on bacterial fitness

J Microbiol. 2014 Mar;52(3):235-42. doi: 10.1007/s12275-014-4083-3. Epub 2014 Mar 1.


Most organisms on the planet have viruses that infect them. Viral infection may lead to cell death, or to a symbiotic relationship where the genomes of both virus and host replicate together. In the symbiotic state, both virus and cell potentially experience increased fitness as a result of the other. The viruses that infect bacteria, called bacteriophages (or phages), well exemplify the symbiotic relationships that can develop between viruses and their host. In this review, we will discuss the many ways that prophages, which are phage genomes integrated into the genomes of their hosts, influence bacterial behavior and virulence.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Bacteria / genetics
  • Bacteria / virology*
  • Bacterial Physiological Phenomena*
  • Prophages / genetics
  • Prophages / physiology*
  • Symbiosis*