Bacterial toxin-antitoxin systems targeting translation

SummaryToxin-antitoxin systems (TAS) emerged more than 25 years ago and have since developed as an important field in molecular microbiology. TAS are autoregulated operons coding a stable toxin and an unstable antitoxin found in the plasmids and chromosomes of Bacteria and Archaea. The conditional activation of their toxins interferes with cell growth/viability and, depending on the context, can influence plasmid maintenance, stress management, bacterial persistence, cell differentiation and, it is likely also bacterial virulence. This review summarizes recent results on the parD system of plasmid R1 and on the chromosomal relBE systems found in Escherichia coli and in Streptococcus pneumoniae with a focus on the RNase activity of their toxins, their regulation and their biomedical applications and implications.