Dept. of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, Kafr El-Sheikh Univ., Kafr El-Sheikh 33516, Egypt.
J Food Sci. 2009 Sep;74(7):M405-10. doi: 10.1111/j.1750-3841.2009.01291.x.
Sixty-nine Escherichia coli and 10 Salmonella isolates, recovered from retail chicken meat in Hiroshima prefecture, Japan, were assayed for antimicrobial susceptibility, the presence of integrons and antimicrobial resistance genes. Twenty-eight out of 69 (40.6%) of E. coli and all 10 Salmonella isolates were exhibited multidrug resistance phenotypes. The most commonly reported resistance phenotypes were against ampicillin, streptomycin, spectinomycin, kanamycin, tetracycline, and trimethoprim/sulfamethoxazole. PCR screening for integrons showed that 8 (11.6%) of the E. coli isolates were positive for the class 1 integrons and 1 isolate (1.4%) was positive for the class 2 integrons. Among the 10 Salmonella isolates, 9 were positive for class 1 integrons and none was positive for class 2 integrons. The identified antibiotic resistance gene cassettes within the class 1 integrons were dfrA1, dfrA7, aadA1, aadB, and catB3, while dfrA1, sat2, and aadA1 were identified within class 2 integron. The beta-lactamase resistance gene bla(TEM-1) was identified in 12 (17.3%) of E. coli isolates and in only one of the Salmonella isolates. The bla(CMY-2) gene, encoding AmpC beta-lactamase, was detected in 16 (23.2%) of the E. coli isolates only. Conjugation experiments demonstrated that there was plasmid-mediated transfer of bla(CMY-2) and bla(TEM-1). These results highlighted the role of retail chicken meat as a potential source for multidrug-resistant strains of E. coli and Salmonella. To the best of our knowledge, this is the 1st report of isolation and molecular characterization of multidrug-resistant strains of E. coli from retail chicken meat in Japan.
69 株大肠杆菌和 10 株沙门氏菌分离株从日本广岛县的零售鸡肉中回收，对其进行了抗菌药敏试验、整合子的存在和抗菌耐药基因检测。69 株大肠杆菌中有 28 株（40.6%）和 10 株沙门氏菌分离株表现出多药耐药表型。最常见的耐药表型是对氨苄西林、链霉素、壮观霉素、卡那霉素、四环素和甲氧苄啶/磺胺甲恶唑。PCR 筛选整合子显示，8 株（11.6%）大肠杆菌分离株呈 1 类整合子阳性，1 株（1.4%）呈 2 类整合子阳性。在 10 株沙门氏菌分离株中，9 株呈 1 类整合子阳性，无 2 类整合子阳性。1 类整合子内鉴定出的抗生素耐药基因盒为 dfrA1、dfrA7、aadA1、aadB 和 catB3，而 2 类整合子内鉴定出的 dfrA1、sat2 和 aadA1。12 株（17.3%）大肠杆菌分离株和仅 1 株沙门氏菌分离株中鉴定出β-内酰胺酶耐药基因 bla(TEM-1)。仅在 16 株（23.2%）大肠杆菌分离株中检测到 bla(CMY-2)基因，该基因编码 AmpC 型β-内酰胺酶。接合实验表明 bla(CMY-2)和 bla(TEM-1)存在质粒介导的转移。这些结果突出了零售鸡肉作为大肠杆菌和沙门氏菌多药耐药株的潜在来源的作用。据我们所知，这是日本首次从零售鸡肉中分离和鉴定多药耐药大肠杆菌的报告。
