For rifampicin we also selected V170F and I491F in rpoB which both confer resistance, are proximal to both S450L and the antibiotic binding site, but are not in the RRDR (Fig. ). I491F is one of the so-called "disputed" mutations which either have variable or borderline rifampicin minimum inhibitory concentrations . For moxifloxacin we also tested E501D in gyrB which is close to the antibiotic binding site but not in the gyrA QRDR (Fig. ).