TABLE 3.

Occurrence and localization of florfenicol resistance genes

Isolate no.Resistance gene(s)Plasmid analysisPCR-directed detection of Tn558 (gene or form detected)
ChromosomePlasmidTypeSize (kb)Plasmid-mediated resistancesatnpAtnpBtnpCtnpB-fexAfexAAlmost complete Tn558Circular form
1fexApSCFS534.8CHL, FFC+++++++
2fexA + cfrpSCFS335.7CLI, CHL, FFC+++
3fexA++++++
4fexA+++++++
5fexApSCFS433.2CHL, FFC+++++++
6fexAcfrpSCFS117.1ERY, CLI, SPT, CHL, FFC+
7cfrpSCFS117.1ERY, CLI, SPT, CHL, FFC
8fexApSCFS234.0CHL, FFC+++++++
9fexAcfrpSCFS117.1ERY, CLI, SPT, CHL, FFC+++++++
10UnknownUnknown
11fexA + cfrpSCFS335.7CLI, CHL, FFC+++
12fexA + cfrpSCFS335.7CLI, CHL, FFC+++
  • a CHL, chloramphenicol; CLI, clindamycin; ERY, erythromycin; FFC, florfenicol; SPT, spectinomycin.