Remarkable Mechanisms in Microbes to Resist Phage Infections

Annu Rev Virol. 2014 Nov;1(1):307-31. doi: 10.1146/annurev-virology-031413-085500. Epub 2014 Jun 27.


Bacteriophages (phages) specifically infect bacteria and are the most abundant biological entities on Earth. The constant exposure to phage infection imposes a strong selective pressure on bacteria to develop viral resistance strategies that promote prokaryotic survival. Thus, this parasite-host relationship results in an evolutionary arms race of adaptation and counteradaptation between the interacting partners. The evolutionary outcome is a spectrum of remarkable strategies used by the bacteria and phages as they attempt to coexist. These approaches include adsorption inhibition, injection blocking, abortive infection, toxin-antitoxin, and CRISPR-Cas systems. In this review, we highlight the diverse and complementary antiphage systems in bacteria, as well as the evasion mechanisms used by phages to escape these resistance strategies.

Keywords: Argonaute; CRISPR-Cas; abortive infection; bacteriophages; horizontal gene transfer; phage resistance; toxin-antitoxin.