13 Bacteriophages of Listeria Steven

Bacteriophages have been shown to influence the evolution of their host and, in several cases, have a major effect on pathogenicity and/or virulence of bacterial pathogens. Several mechanisms allow phages to change the biology and associated phenotypes of their host. This chapter aims at explaining these mechanisms in the context of Listeria evolution and pathogenesis, using examples from other pathogens. Our current knowledge on the biology and applications of a few selected Listeria phages is reviewed and discussed. The lack of evidence for their influence on the phenotype of lysogenized host bacteria likely reflects our fragmentary knowledge about Listeria phages, especially on the molecular level. Clearly, much more research is required to understand the full impact of phages on their hosts, both in an ecological and evolutionary context. 13.1. Bacteriophages 13.1.