DosR regulon and recovery from extended exposure to a low dose of NO. DETA-NO (100 μM) was added to aerobic growing H37Rv, DorKO, or DorCO cultures every 6 h over a 36-h period. Growth was followed by determining the OD600. Squares, strain H37Rv; triangles, DorKO; circles, DorCO; open symbols, control; filled symbols, NO added.