Toxin-antitoxin (TA) systems are ubiquitous genetic elements in bacteria that consist of a
growth-inhibiting toxin and its cognate antitoxin. These systems are prevalent in bacterial …

Bacteria are under immense evolutionary pressure from their viral invaders—
bacteriophages. Bacteria have evolved numerous immune mechanisms, both innate and …

CRISPR–Cas adaptive immune systems are widespread among bacteria and archaea.
Recent studies have shown that these systems have minimal long-term evolutionary effects …

Over the past century, Escherichia coli has become one of the best studied organisms on
earth. Features such as genetic tractability, favorable growth conditions, well characterized …

Prokaryotes have numerous mobile genetic elements (MGEs) that mediate horizontal gene
transfer (HGT) between cells. These elements can be costly, even deadly, and cells use …

Bacteria and their viral predators (bacteriophages) are locked in a constant battle. In order to
proliferate in phage-rich environments, bacteria have an impressive arsenal of defence …

Phages are now acknowledged as the most abundant microorganisms on the planet and
are also possibly the most diversified. This diversity is mostly driven by their dynamic …

Restriction-modification (RM) systems are ubiquitous and are often considered primitive
immune systems in bacteria. Their diversity and prevalence across the prokaryotic kingdom …

Host range describes the breadth of organisms a parasite is capable of infecting, with limits
on host range stemming from parasite, host, or environmental characteristics. Parasites can …

Horizontal genetic transfer (HGT) has played an important role in bacterial evolution at least
since the origins of the bacterial divisions, and HGT still facilitates the origins of bacterial …