FlmA-FlmB toxin-antitoxin system

The FlmA-FlmB toxin-antitoxin system consists of FlmB RNA (F leading-region maintenance B), a family of non-coding RNAs and the protein toxin FlmA. The FlmB RNA transcript is 100 nucleotides in length and is homologous to sok RNA from the hok/sok system and fulfills the identical function as a post-segregational killing (PSK) mechanism. flmB is found on the F-plasmid of Escherichia coli and Salmonella enterica.

Source: Wikipedia — FlmA-FlmB toxin-antitoxin system (CC BY-SA 4.0)