This family is conserved in Bacteria. It confers resistance to kanamycin, gentamicin, and tobramycin [1]. The protein is also produced by plasmids in various bacterial species and confers resistance to essentially all clinically available aminoglycosides except streptomycin, and it eliminates the synergism between aminoglycosides and cell-wall active agents [2].

1: Nucleotide sequence of the AAD(2'') aminoglycoside adenylyltransferase determinant aadB. Evolutionary relationship of this region with those surrounding aadA in R538-1 and dhfrII in R388. Cameron FH, Groot Obbink DJ, Ackerman VP, Hall RM; Nucleic Acids Res. 1986;14:8625-8635. PMID:3024112

2: Insertion sequence ISEcp1-like element connected with a novel aph(2'') allele [aph(2'')-Ie] conferring high-level gentamicin resistance and a novel streptomycin adenylyltransferase gene in Enterococcus. Chen YG, Qu TT, Yu YS, Zhou JY, Li LJ; J Med Microbiol. 2006;55:1521-1525. PMID:17030911