Antitoxin component of a type II toxin-antitoxin (TA) system. Upon expression in E.coli and M.smegmatis neutralizes the effect of cognate toxin MazF3. Overexpression of MazE3 alone decreased persister cells formation in M.smegmatis upon challenge with gentamicin or kanamycin. Forms a complex with cognate toxin MazF3, possibly with 1:1 stoichiometry. Mildly induced (about 4-fold) when grown in a non-replicating state.