TABLE 2.

Antimicrobial susceptibilities of A. faecalis FL-424/98, E. coli DH5α(pFL424), and E. coli DH5α containing various pFL424 subclonesa

Antimicrobial agentsMIC (μg/ml)b
FL-424/98 (strAB, aphA6b, blaPER-1)DH5α(pFL424) (strAB, aphA6b, blaPER-1)DH5α(pEM-43) (aphA6b)DH5α(pEM-9/rh) (aphA6b)DH5αc (none)
Ampicillin>128>128d2
Piperacillin8640.5
Cephalothin64>1288
Cefotaxime128>128≤0.12
Ceftazidime>128>128≤0.12
Cefepime>12864≤0.12
Aztreonam>128>128≤0.12
Chloramphenicol160.50.5
Tetracycline40.250.25
Streptomycin>12832221
Spectinomycin>12816161616
Kanamycin>128432161
Gentamicin160.120.250.120.12
Sisomicin320.250.250.250.25
Tobramycin>12810.50.50.5
Netilmicin160.250.250.250.25
Amikacin>1280.5210.5
  • a For details on the subclones, see Fig. 1. The antimicrobial susceptibility of DH5α is also shown for comparison.

  • b The presence of the resistance gene(s) investigated in this work is reported in parentheses.

  • c The MICs of aminoglycosides for E. coli DH5α(pBC-SK) were identical to those for DH5α.

  • d —, not determined.