Type II toxin-antitoxin loci: The mazEF family

Abstract

The mazEF locus is one of the most extensively characterized toxin-antitoxin (TA) systems. MazF is an endoribonuclease that cleaves RNA at a specific sequence. MazF is conserved in most bacterial and some archaeal species. Since the discovery of MazF in Escherichia coli, a number of MazF homologues and other mRNA interferases with different mRNA cleavage specificities have been elucidated. Here we describe their unique biochemical features, the regulatory mechanisms of the MazF activity and presumed physiological roles of MazF in the cells.