Mutations in the superoxide-responsive regulator SoxR confer fluoroquinolone resistance in Stenotrophomonas maltophilia
Highlights • soxR mutations cause constitutive activation of SmeVWX and MfsA efflux pumps. • Mutations in soxR confer resistant to levofloxacin, a drug option for S. maltophilia. • Single R49 substitution activates SoxR and drives multidrug resistance.