Submitted to: Safepork
Publication Type: Abstract Only
Publication Acceptance Date: 7/6/2005
Publication Date: 9/6/2005
Citation: McCuddin, Z.P., Carlson, S.A. 2005. Incursion of the DT104 multiresistance locus into Salmonella Choleraesuis [abstract]. Safepork. p. 302-303.
Technical Abstract: The increasing prevalence of multi-drug resistance in pathogenic bacteria is a significant problem for food safety. Salmonella enterica serovar Typhimurium DT104, which is a global health concern and infects a broad range of mammalian hosts, has been shown to carry a chromosomal integron (SGI-1) which encodes multiple antibiotic resistance: ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (ACSSuT). The portion of this integron encoding antibiotic resistance is 13 kb and the remaining 30 kb is of unknown function but may contribute to hypervirulence in DT104. The SGI-1 antibiotic resistance gene cluster has subsequently been identified in other serovars suggesting lateral transfer of this element. Host-adapted Salmonella have been assessed for the SGI-1 integron. Isolates of S. choleraesuis, the swine-adapted serovar, with the ACSSuT phenotype have been recovered from pooled clinical isolates. Full sequencing of the SGI-1 is underway. Characterization of this integron provides insight into antibiotic resistance, virulence, and SGI-1 transfer between pathogens.