Open AccessCharacterization of class 1 integrons‐mediated antibiotic resistance among calf pathogenic Escherichia coli
Author(s) -
Du Xiangdang,
Shen Zhangqi,
Wu Beibei,
Xia Shengchao,
Shen Jianzhong
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2005.03.021
Subject(s) - biology , microbiology and biotechnology , escherichia coli , antibiotic resistance , virulence , gene cassette , antibiotics , drug resistance , integron , gene , genetics
Escherichia coli isolates from calf diarrhea cases ( n = 22 ) in the Beijing surrounding region in China were characterized for disease serotype, virulence factors, antimicrobial susceptibility pattern and class 1 integrons. 59% ( n = 13 ) of the isolates were positive for the int I1 gene. The presence and genetic content of class 1 integrons in 13 E. coli isolates were examined by PCR and sequencing. Sequencing analysis revealed six gene cassettes, which encoded resistance to trimethoprim ( dfrA1 , dfrA17 ), aminoglycosides ( aadB , aadA1 and aadA5 ) and chloramphenicol ( cmlA ). The gene cassette arrays dfrA1–orf (45%) and aadB–orf–cmlA (32%) were most prevalent among these isolates. These data revealed the high prevalence of class 1 integrons among calf pathogenic E. coli isolates in the Beijing surrounding region in China, which may provide important and useful surveillance information reflecting specific antibiotic selective pressure.