Characteristic Resistance Mechanism of Mycobacterium tuberculosis to DC-159a, a New Respiratory Quinolone

A G88C mutation in GyrA is one of the key alterations by which Mycobacterium tuberculosis mutants acquire DC-159a resistance in vitro. A novel double mutation in GyrA, G88C D94H, conferred high DC-159a resistance. Different mutation patterns in GyrA were demonstrated for DC-159a-resistant mutants and quinolone-resistant multidrug-resistant (QR-MDR) M. tuberculosis isolates, with a mutation either at position 90 or 94 and double mutations at 90 and 91 or at 90 and 94. DC-159a might be promising for QR M. tuberculosis treatment.