Detection of Class 1 and 2 Integrons, β-Lactamase
Genes and Molecular Characterization of Sulfonamide Resistance in
Escherichia coli Isolates
Recovered from Poultry in China
Jam Kashif, Rehana Buriro, Javed Memon, Muhammad
Yaqoob, Jamila Soomro, Diao Dongxue, Huang Jinhuand WangLiping*
Key Lab of Veterinary Pharmacology, College of
Veterinary Medicine, Nanjing Agricultural University, Nanjing
210095; Peoples Republic of China
*Corresponding author: wlp71@163.com
Abstract
This study aimed to detect integrons,
β-lactamase genes and to
characterize sulfonamide resistant E. coli
isolates recovered from poultry. All the isolates (n=38) were investigated
for the presence of integrons,
Sul1, Sul2,
Sul3 genes by PCR.
Class 1 and class 2 integron were present in 79 and 16%, respectively.
Additional resistance gene cassette embedded in class 1 and 2 integrons
was aadA1, aadA5, dfrA17 and
aadA22, dfrA, respectively.
Sul1 and
Sul2 genes were detected in 42.1 and 60.5% isolates, respectively.
Both the Sul1 and
Sul2 were present in 23% isolates.
However, Sul3 gene was not present.
Co-existence of Sul1 and Sul2 with class 1
integrons was found in 28.9 and 60.5% of class 1 integron positive isolates,
respectively. Whereas, a less percentage of isolates showed a low level of
resistance to β-lactams and no blaCTX-M,
blaSHV and blaTEM was found. The MIC results showed resistance to
sulfadiazine and sulfamethoxazole-trimethoprim in 88 and 84% isolates,
resistance to penicillin, ampicillin, amoxicillin was 52, 52 and 44%,
respectively. Chloramphenicol, florfenicol, tetracycline and gentamycin
resistance was found in 51, 5, 42 and 67% isolates, respectively. This study
revealed high frequency of class 1 integrons,
Sul genes among poultry
E. coli isolates, therefore further spread of
Sul genes and integrons is
predictable.
Key words: β-lactamase, E. coli, Integrons, Poultry, Sul genes