TABLE 3.

Topoisomerase mutations and OST in selected clinical isolates of K. pneumoniae

IsolateaCiprofloxacin MIC (μg/ml)Amino acid at DNA gyrase A position:Amino acid at topoisomerase IV position 80OSTb
8387
S80.5Ser→Tyrc
S382Ser→Tyr
S284Ser→TyrC, P
S294Ser→LeuAsp→AsnC, P
S308Ser→TyrC
S378Ser→TyrC
S716Ser→TyrSer→IleC, P
S916Ser→TyrAsp→AsnSer→Trp
S1216Ser→IleAsp→AsnSer→Ile
S1032Ser→TyrAsp→AsnSer→ArgC
S2732Ser→TyrAsp→AsnSer→Ile
S3332Ser→TyrAsp→AsnSer→Ile
S3432Ser→IleSer→Ile
S564Ser→TyrAsp→AsnSer→IleC
S1364Ser→TyrAsp→AsnSer→TrpC
S3164Ser→TyrAsp→AsnSer→Trp
S4264Ser→Tyr
S6128Ser→TyrAsp→AsnSer→ArgC
S32128Ser→TyrSer→Trp
S36128Ser→TyrAsp→AsnSer→TrpC
  • a Isolates are listed by increasing ciprofloxacin MIC.

  • b C, resistant to cyclohexane; P, resistant to pentane; −, no growth in the presence of cyclohexane or pentane.

  • c —, no change at specified amino acid.