Salmonella enterica Serovar Typhi Strains Isolated in Korea Containing a Multidrug Resistance Class 1 Integron

摘要

Six strains of Salmonella enterica serovar Typhi which were resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, streptomycin, tetracycline, and gentamicin were isolated in Korea. This multidrug resistance was transferred by a conjugative plasmid of about 50 kb. The plasmid harbored a class 1 integron, which included six resistance genes, aacA4b, catB8, aadA1, dfrA1, aac(6′)-IIa, and the novel blaP2, in that order. All of the isolates showed the same-size plasmids and the same ribotyping patterns, which suggests a clonal spread of these multidrug-resistant isolates.