AcrD of Escherichia coli is an aminoglycoside efflux pump

AcrD, a transporter belonging to the resistance-nodulation-division family, was shown to participate in the efflux of aminoglycosides. Deletion of the acrD gene decreased the MICs of amikacin, gentamicin, neomycin, kanamycin, and tobramycin by a factor of two to eight, and Delta acrD cells accumulated higher levels of [H-3]dihydrostreptomycin and [H-3]gentamicin than did the parent strain.