title: Identification and molecular characterization of antimicrobial-resistant shiga toxin-producing Escherichia coli isolated from retail meat products.
abstract: Ten (2.7%) Shiga toxin-producing Escherichia coli (STEC) were isolated from 370 samples of raw minced beef, mutton, pork, and chicken from the Jilin region of China; and additional 10 E. coli O157:H7 isolates were previously isolated from different Jilin regions. Seventeen of the isolates were multiresistant, exhibiting resistance to ampicillin, ciprofloxacin, tetracycline, sulfamethoxazole-trimethoprim, gentamycin, and streptomycin. Class 1 integrons were detected in nine (45.0%) of the STEC isolates and consisted of serogroups O157, O62, O113, O149, and O70. Integrons containing amplicons of a 0.5-1.5 or 1.0 kb gene cassette were found in seven (77.8%) of the integron-containing isolates. Sequencing analysis revealed that these gene cassettes encode genes conferring resistance to trimethoprim (dfrA1) and streptomycin (aadA1). The 0.5 kb cassette described here was found to encode a putative transporter peptide in the STEC. Seventeen isolates contained plasmids with different bands, and transfer by conjugation between strains of E. coli demonstrated that class 1 integrons located on mobile plasmids could contribute to the emergence and dissemination of antimicrobial resistance to ampicillin, gentamycin, streptomycin, and sulfamethoxazole-trimethoprim amongst STEC. These data revealed the high prevalence of antimicrobial-resistant STEC isolates in Jilin's surrounding regions, providing important and useful surveillance information reflecting antimicrobial selection pressure.
authors: Department of Pathogenobiology, Norman Bethune College of Medical Sciences, Jilin University, Changchun, Jilin, People's Republic of China.
authors: Ming-Cheng
authors: MC
authors: Li
authors: Fang
authors: F
authors: Wang
authors: Fan
authors: F
authors: Li
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002681:China; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D019453:Escherichia coli O157 / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D032023:Integrons; D008461:Meat Products / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction; D054323:Shiga-Toxigenic Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D013045:Species Specificity; D013307:Streptomycin / Q000494:pharmacology; D014296:Trimethoprim Resistance / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D013307:Streptomycin