TY - JOUR
T1 - Antimicrobial resistance in nontyphoidal Salmonella from food sources in Colombia
T2 - Evidence for an unusual plasmid-localized class 1 integron in serotypes typhimurium and anatum
AU - O'Mahony, Rebecca
AU - Quinn, Teresa
AU - Drudy, Denise
AU - Walsh, Ciara
AU - Whyte, Paul
AU - Mattar, Salim
AU - Fanning, Séamus
PY - 2006/12
Y1 - 2006/12
N2 - Seventy-two isolates representing 18 serotypes recovered from various food samples collected in Colombia were tested for antimicrobial susceptibilities. The collection was further characterized for extended-spectrum cephalosporin, aminoglycoside, and tetracycline resistance markers. Multidrug resistant (MDR) isolates were further investigated for class 1 integrons and were evaluated for the presence of conjugative plasmids along with a determination of the incompatibility group by polymerase chain reaction (PCR). Antibiogram analysis showed that the incidence rate of ceftiofur resistance was moderately high (15%). A similar level of resistance to neomycin and oxytetracycline (11% and 10%, respectively) was also observed. There was a high prevalence of gene cassettes as part of one or more class 1 integrons (61%), many of which contained determinants that contributed to the resistance profile. Class 1 integrons identified in MDR Salmonella enterica serotypes Typhimurium and Anatum isolates were characterized. Sequencing identified several incomplete open reading frames (ORFs) as part of a gene cassette (bla-imp-13, dfr7, blr1088, and aac8) along with a complete gene cassette (bla-oxa2) in each case. A mosaic of gene cassettes was identical in the two Salmonella serotypes. These integrons were located to a conjugative replicon. Plasmid profiling and incompatibility typing identified three plasmids belonging to Inc groups A/C, P, and W. Our study highlights the role of integrons, contributing to a MDR phenotype that is capable of dissemination to other bacteria.
AB - Seventy-two isolates representing 18 serotypes recovered from various food samples collected in Colombia were tested for antimicrobial susceptibilities. The collection was further characterized for extended-spectrum cephalosporin, aminoglycoside, and tetracycline resistance markers. Multidrug resistant (MDR) isolates were further investigated for class 1 integrons and were evaluated for the presence of conjugative plasmids along with a determination of the incompatibility group by polymerase chain reaction (PCR). Antibiogram analysis showed that the incidence rate of ceftiofur resistance was moderately high (15%). A similar level of resistance to neomycin and oxytetracycline (11% and 10%, respectively) was also observed. There was a high prevalence of gene cassettes as part of one or more class 1 integrons (61%), many of which contained determinants that contributed to the resistance profile. Class 1 integrons identified in MDR Salmonella enterica serotypes Typhimurium and Anatum isolates were characterized. Sequencing identified several incomplete open reading frames (ORFs) as part of a gene cassette (bla-imp-13, dfr7, blr1088, and aac8) along with a complete gene cassette (bla-oxa2) in each case. A mosaic of gene cassettes was identical in the two Salmonella serotypes. These integrons were located to a conjugative replicon. Plasmid profiling and incompatibility typing identified three plasmids belonging to Inc groups A/C, P, and W. Our study highlights the role of integrons, contributing to a MDR phenotype that is capable of dissemination to other bacteria.
UR - http://www.scopus.com/inward/record.url?scp=33845678045&partnerID=8YFLogxK
U2 - 10.1089/mdr.2006.12.269
DO - 10.1089/mdr.2006.12.269
M3 - Article
SN - 1076-6294
VL - 12
SP - 269
EP - 277
JO - Microbial Drug Resistance
JF - Microbial Drug Resistance
IS - 4
ER -