Table 3

Genotypes of quinolone resistance-determining regionsa

QRDR genotypeNo. (%) of isolates
ST131-O25bST131-O16ST405OST
CIPr NALr (n = 37)CIPr NALr (n = 5)CIPs NALr (n = 13)CIPr NALr (n = 41)CIPr NALr (n = 22)CIPs NALr (n = 10)
Four mutations
    LNIV36 (97)0 (0)0 (0)0 (0)0 (0)0 (0)
    LNIG0 (0)0 (0)0 (0)4 (10)3 (14)0 (0)
    LNIK0 (0)0 (0)0 (0)3 (7)0 (0)0 (0)
Three mutations
    LNIE0 (0)3 (60)0 (0)26 (63)16 (73)0 (0)
    LYIE0 (0)0 (0)0 (0)7 (17)0 (0)0 (0)
    LNRE0 (0)2 (40)0 (0)0 (0)0 (0)0 (0)
    LNSK1 (3)0 (0)0 (0)0 (0)1 (5)0 (0)
    LGRE0 (0)0 (0)0 (0)0 (0)1 (5)0 (0)
    LVRE0 (0)0 (0)0 (0)0 (0)1 (5)0 (0)
Two mutations
    LDIE0 (0)0 (0)0 (0)1 (2)0 (0)1 (10)
    LESE0 (0)0 (0)0 (0)0 (0)0 (0)1 (10)
One mutation
    LDSE0 (0)0 (0)10 (77)0 (0)0 (0)6 (60)
    SGSE0 (0)0 (0)3 (23)0 (0)0 (0)0 (0)
    ADSE0 (0)0 (0)0 (0)0 (0)0 (0)1 (10)
    SNSE0 (0)0 (0)0 (0)0 (0)0 (0)1 (10)
Wild type (SDSE)0 (0)0 (0)0 (0)0 (0)0 (0)0 (0)
  • a OST, other sequence types; CIP, ciprofloxacin; NAL, nalidixic acid; r, resistant; s, sensitive; QRDR, quinolone resistance-determining region. QRDR genotypes are shown sequentially by the deduced amino acids of GyrA codons 83 and 87 and ParC codons 80 and 84. All nalidixic acid-susceptible isolates in any clonal group had wild-type QRDRs.