Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung, Taiwan.
Comp Immunol Microbiol Infect Dis. 2013 Jan;36(1):9-16. doi: 10.1016/j.cimid.2012.08.004. Epub 2012 Sep 8.
A total of 499 Salmonella isolates including 9 serovars from humans and various animal hosts were collected to compare prevalence of integron and antimicrobial resistance. The integron and gene cassette were detected by PCR, and then the gene cassette type was further determined by sequencing and restriction fragment length polymorphism (RFLP) analysis. The antimicrobial susceptibility test was conducted by disk diffusion method. The positivity percentage of class 1 integron and the diversity of gene cassettes carried by integron were quite different in various Salmonella serovars, especially comparing those from animals to humans. After sequencing and RFLP analysis, it was identified eight gene cassette types. The gene cassette type D carrying ampicillin/streptomycin resistance genes was the most common one (42.2%) in the integron-positive isolates. More diversity of gene cassette types was identified in humans comparing to that in animals. Several gene cassette types were identified for the first time in some Salmonella serovars. In this study, 31.5% (157/499) of the isolates were multi-resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (ACSSuT). S. Choleraesuis isolates with the cassette type A1, but S. Typhimurium isolates with the cassette type E1, were frequently associated with ACSSuT-resistant (80.6% and 72.7%, respectively). There was a significant association between the presence of class 1 integron and quinolone resistance in S. Choleraesuis isolates, but not in S. Typhimurium. Our findings imply that transmission efficiency of various gene cassettes through the integron could be different in various Salmonella serovars.
共收集了 499 株包括 9 个人类和各种动物宿主血清型的沙门氏菌分离株，以比较整合子和抗菌药物耐药性的流行率。通过 PCR 检测整合子和基因盒，然后通过测序和限制性片段长度多态性（RFLP）分析进一步确定基因盒类型。采用纸片扩散法进行抗菌药物敏感性试验。各种沙门氏菌血清型的 1 类整合子阳性率和整合子携带的基因盒多样性差异很大，特别是比较动物来源和人类来源的分离株。测序和 RFLP 分析后，确定了 8 种基因盒类型。携带氨苄西林/链霉素耐药基因的基因盒类型 D 是整合子阳性分离株中最常见的（42.2%）。与动物来源的分离株相比，人类来源的分离株中基因盒类型的多样性更多。在一些沙门氏菌血清型中首次鉴定出几种基因盒类型。在本研究中，31.5%（157/499）的分离株对氨苄西林、氯霉素、链霉素、磺胺甲恶唑和四环素（ACSSuT）耐药。携带基因盒类型 A1 的 S. Choleraesuis 分离株和携带基因盒类型 E1 的 S. Typhimurium 分离株与 ACSSuT 耐药密切相关（分别为 80.6%和 72.7%）。S. Choleraesuis 分离株中 1 类整合子的存在与喹诺酮类药物耐药之间存在显著相关性，但 S. Typhimurium 分离株中则无。我们的研究结果表明，各种基因盒通过整合子的传递效率在不同的沙门氏菌血清型中可能不同。
