Abstract:
We have identified a second lin gene in a gene cassette. This cassette was recovered from a multiply antibiotic-resistant Salmonella enterica serovar Stanley strain (SRC54) isolated in 2001 from a traveler who had recently returned from Thailand. This strain was resistant to chloramphenicol, gentamicin, kanamycin, spectinomycin, streptomycin, sulfathiazole, and tetracycline but susceptible to ampicillin and nalidixic acid at levels described previously (6). It displayed intermediate resistance to ciprofloxacin. The gene cassette array was amplified by using standard primers (L2 and R1) in the 5' conserved sequence and 3' conserved sequence of class 1 integrons, and the 2.25-kb amplicon was cloned into pPCRscript and sequenced as previously described (see reference 6 for primer details). E. coli strain DH5{alpha} containing pPCR-Script with the cassette array was at least 10-fold more resistant to lincomycin (MIC, ?2,000 µg/ml) than DH5{alpha} containing only pPCR-Script (MIC, 180 µg/ml).
