Molecular characterization of class 1 integrons from Irish thermophilic Campylobacter spp.
OBJECTIVE
In this study a large random collection (n = 378) of Irish thermophilic Campylobacter isolates were investigated for the presence of integrons, genetic elements associated with the dissemination of antimicrobial resistance.


METHODS
Purified genomic DNA from each isolate was analysed by PCR for the presence of class 1 integrons. Four gene cassette-associated amplicons were completely characterized.


RESULTS
Sixty-two of the isolates possessed a complete class 1 integron with a recombined gene cassette located within a 1.0 kb amplicon containing an aadA2 gene. This cassette was present in both Campylobacter jejuni and Campylobacter coli isolates and following sequence analysis was shown to be similar to sequences recently reported in Salmonella enterica Hadar and on an 85 kb plasmid conferring quinolone resistance in Escherichia coli.


CONCLUSIONS
Aminoglycoside aadA2-encoding class 1 integrons were identified among unrelated Campylobacter spp. Amino acid sequence comparisons revealed identical structures in both Salmonella and E. coli. The presence of class 1 integrons in Campylobacter spp. may be significant should these organisms enter the food chain and especially when antimicrobial treatment for severe infections is being considered.
O'Halloran
Fiona
F
Molecular Diagnostics Unit, Cork Institute of Technology, Bishopstown, Cork, Ireland.
Lucey
Brigid
B
Cryan
Bartley
B
Buckley
Tom
T
Fanning
Séamus
S
D000818:Animals; D002167:Campylobacter / Q000187:drug effects / Q000235:genetics*; D002169:Campylobacter Infections / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics; D006801:Humans; D032023:Integrons / Q000235:genetics*; D007494:Ireland; D008969:Molecular Sequence Data; D009713:Nucleotidyltransferases / Q000235:genetics; D011200:Poultry; D020133:Reverse Transcriptase Polymerase Chain Reaction
D004269:DNA, Bacterial; D009713:Nucleotidyltransferases; C020565:gentamicin 2''-nucleotidyltransferase