abkBA toxin-antitoxin system may act as antipersister modules in clinical isolates.

Persistence cells comprise a subpopulation of bacteria that is resistant to treatment. In this study, the role of the toxin-antitoxin (TA) system in the formation of persistence cells of isolates was investigated. After confirming all isolates, TA systems abkBA, mqsRA and higBA were identified. Persister cells were confirmed using the standard method. Real-time PCR was used to compare the expression of TA systems in isolates in persistence and normal states. The abkAB system was present in all isolates; 4% of isolates formed persister cells. The expression level of the  gene in persistent isolates showed a sevenfold increase compared with nonpersistent isolates.  The abkBA system is proposed as an antipersistence target in isolates.