TABLE 2.

Topoisomerase amino acid alterations and MICs of levofloxacin and gatifloxacin for levofloxacin-resistant S. pneumoniae isolates collected during year 1 of the PROTEKT US study (2000-2001)

No. of isolatesAmino acid alteration in the following QRDR:Total no. of amino acid changesMIC range (mg/liter)
gyrAgyrBparCparELevofloxacinGatifloxacin
1S81F182
1S79F16>4
1D435N>164
22S81FS79F28->164->4
8S81FS79Y8-164->4
8S81FD435N8-164
7E85KS79F32>4
3S81YS79Y8-164->4
2E85KD435N8-162-4
2S81FD83Y82
1E85GS79F82
1S81FD83N82
1S81FS79A84
1S81YS79F164
1Q90HE474K84
1S79FD435N>16>4
7E85KS79FE474K3>16>4
1E85KK136TaD435N82
1E85KS79FD435N>16>4
1S81FS79YA325V16>4
1S81FS79Y, D83G164
1S81FD435N, E474K164
1S81YS79F, D83N>16>4
1D435ND435N, E474K164
1S81FS52GD435N84
1S81F, E85QS80PD435N4>16>4
1S81F, S114GS52G, S79Y, N91D516>4
1S81F, S114GS52G, D83N, N91DV144I, T186I, I241T882
1S81F, S114GS52G, S79R, N91DK214E, T2161, I241T, I493L916>4
1S81F, S114GS52G, S79R, N91D, E135DT157M, G163A, 1241T, A425S10164
  • a Uncommon amino acid substitutions that probably play no role in fluoroquinolone resistance are shown in boldface.