Table 2.

Amino acid changes encoded by mutations in thegyrA and parC gene loci and corresponding fluoroquinolone MICs (mg/litera)

Mutant in locusnAntibioticNo. of isolates for which corresponding MICs were
gyrAparC≤0.060120.250.512481632≥64
29Ciprofloxacin161471
Levofloxacin16175
Gatifloxacin13196
Sparfloxacin110972
Trovafloxacin51761
Grepafloxacin31772
Moxifloxacin21782
Clinafloxacin1811
Sitafloxacin245
Arg-95→Cys2Ciprofloxacin11
Levofloxacin11
Gatifloxacin2
Sparfloxacin11
Trovafloxacin11
Grepafloxacin11
Moxifloxacin2
Clinafloxacin11
Sitafloxacin2
Lys-137→Asn6Ciprofloxacin132
Levofloxacin42
Gatifloxacin6
Sparfloxacin24
Trovafloxacin15
Grepafloxacin6
Moxifloxacin6
Clinafloxacin33
Sitafloxacin6
Ser-79→Phe2Ciprofloxacin11
Levofloxacin11
Gatifloxacin11
Sparfloxacin11
Trovafloxacin11
Grepafloxacin11
Moxifloxacin2
Clinafloxacin2
Sitafloxacin2
Ser-81→Phe2Ciprofloxacin11
Levofloxacin11
Gatifloxacin11
Sparfloxacin11
Trovafloxacin11
Grepafloxacin11
Moxifloxacin11
Clinafloxacin11
Sitafloxacin2
Ser-81→Tyr3Ciprofloxacin111
Levofloxacin3
Gatifloxacin111
Sparfloxacin21
Trovafloxacin12
Grepafloxacin12
Moxifloxacin12
Clinafloxacin12
Sitafloxacin122
Ser-81→PheAsp-78→Asn1Ciprofloxacin1
Levofloxacin1
Gatifloxacin1
Sparfloxacin1
Trovafloxacin1
Grepafloxacin1
Moxifloxacin1
Clinafloxacin1
Sitafloxacin1
Ser-81→PheSer-79→Phe16Ciprofloxacin4633
Levofloxacin844
Gatifloxacin385
Sparfloxacin2464
Trovafloxacin1366
Grepafloxacin466
Moxifloxacin592
Clinafloxacin871
Sitafloxacin88
Ser-81→PheSer-79→Phe4Ciprofloxacin22
Lys-137→AsnLevofloxacin22
Gatifloxacin22
Sparfloxacin13
Trovafloxacin22
Grepafloxacin112
Moxifloxacin31
Clinafloxacin121
Sitafloxacin211
Ser-81→PheLys-137→Asn2Ciprofloxacin2
Asp-83→AsnLevofloxacin2
Gatifloxacin2
Sparfloxacin2
Trovafloxacin11
Grepafloxacin11
Moxifloxacin11
Clinafloxacin2
Sitafloxacin11
Ser-81→PheAsp-78→Asn1Ciprofloxacin1
Arg-95→CysLevofloxacin1
Gatifloxacin1
Sparfloxacin1
Trovafloxacin1
Grepafloxacin1
Moxifloxacin1
Clinafloxacin1
Sitafloxacin1
Ser-81→PheAsp-78→Asn1Ciprofloxacin1
Lys-137→AsnLevofloxacin1
Gatifloxacin1
Sparfloxacin1
Trovafloxacin1
Grepafloxacin1
Moxifloxacin1
Clinafloxacin1
Sitafloxacin1
  • a A dash (—) denotes a wild-type sequence with no mutations identified. Position numbers are based on the gyrA (3) and parC (18,20) sequence of S. pneumoniae.