Characterization of Plasmid-Mediated aphA-3 Kanamycin Resistance in Campylobacter jejuni

• Published in: Microbial drug resistance (Larchmont, N.Y.) Vol. 10; no. 2; pp. 98 - 105
• Main Authors: Gibreel, Amera, Sköld, Ola, Taylor, Diane E.
• Format: Journal Article
• Language: English
• Published: United States Mary Ann Liebert, Inc 01.06.2004
• Subjects: Base Sequence; Campylobacter coli; Campylobacter jejuni; Campylobacter jejuni - drug effects; Campylobacter jejuni - genetics; Campylobacter jejuni - isolation & purification; Campylobacter jejuni/drug effects/genetics/isolation & purification; Canada; DNA Primers; DNA, Bacterial - genetics; DNA, Bacterial - isolation & purification; Drug resistance; E coli; Egypt; Electrophoresis; Food Microbiology; Geography; Humans; Kanamycin Resistance - genetics; Mechanisms; Microbial Sensitivity Tests; Plasmids - genetics; Polymerase Chain Reaction; Restriction Mapping; Sweden; Canada; Sweden; Egypt; Bacterial/genetics/isolation & purification; Research Support; Non-U.S. Gov't; DNA
• ISSN: 1076-6294; 1931-8448
• DOI: 10.1089/1076629041310127

A total of 254 isolates of Campylobacter jejuni and three isolates of Campylobacter coli , isolated from Sweden, Canada, and Egypt, were screened for kanamycin resistance. Eight strains of C. jejuni contained large plasmids that carried the aphA-3 kanamycin-resistance marker. In six plasmids, the aphA-3 gene was located downstream of an apparent insertion sequence, designated IS 607 *, which showed a considerable similarity to IS 607 , characterized on the chromosome of some Helicobacter pylori strains. In contrast, the other plasmids carried the aphA-3 gene as a part of a resistance cluster. This included three resistance markers encoding 6′-adenylyltransferase ( aadE ), streptothricin acetyltransferase ( sat ), and 3′-aminoglycoside phosphotransferase type III ( aphA-3 ). The genetic organization of this resistance cluster suggests that it has been acquired by C. jejuni from a Gram-positive organism. The IS 607 * element was also observed in kanamycin-susceptible strains of C. jejuni on plasmids mediating tetracycline resistance. The kanamycin-resistance phenotype transferred along with tetracycline resistance by conjugation from four representative C. jejuni strains to a recipient strain of C. jejuni . The kanamycin-resistance determinant ( aphA-3 ) was stably transferred from one of the four C. jejuni strains to a recipient strain of Escherichia coli . However, the C. jejuni plasmid, which also carries the tetO gene, was not maintained in E. coli . Pulsed-field gel electrophoresis revealed the integration of approximately 50 kb of the plasmid into the chromosome of the E. coli recipient.