Molecular Epidemiology of Salmonella enterica Serovar Typhimurium Isolates from Cattle in Hokkaido, Japan: Evidence of Clonal Replacement and Characterization of the Disseminated Clone
Molecular Epidemiology of Salmonella enterica Serovar Typhimurium Isolates from Cattle in Hokkaido, Japan: Evidence of Clonal Replacement and Characterization of the Disseminated Clone
复制标题
DOI：
10.1128/aem.01910-10
复制
发表时间：
2011-03-01
影响因子：
4.4
通讯作者：
Akiba, Masato
中科院分区：
文献类型：
--
作者：
Tamamura, Yukino;Uchida, Ikuo;Akiba, Masato
使用脉冲场凝胶电泳 (PFGE) 对 1977 年至 2009 年间从日本北海道牛身上收集的 545 株鼠伤寒沙门氏菌分离株进行了分子流行病学研究。从 116 个 PFGE 模式中识别出 9 个主要簇。簇 I 包含 248 个分离株，其中 243 个具有针对最终噬菌体类型 104 (DT104) 或 U302 的特异性序列。 1993 年至 2003 年，I 簇分离株占主导地位，但从 2004 年开始，其数量开始下降。从 2002 年开始，观察到 VII 簇分离株数量有所增加，其中包括 21 个 PFGE 模式，其中 165 个分离株。通过多位点可变数量串联重复分析 (MLVA) 分析了代表 116 个 PFGE 图谱的总共 116 个分离株。除 2 个药物敏感分离株外，第 VII 簇内的 19 个分离株被 MLVA 分类为同一簇。在第VII簇分离株中，对氨苄西林、氯霉素、链霉素、磺胺类、四环素、卡那霉素、头孢唑林、磺胺甲恶唑甲氧苄啶耐药的抗生素耐药型和对氨苄西林、链霉素、磺胺类、四环素、卡那霉素耐药的耐药型分别为23株和125株。在代表 VII 簇的 19 个分离株中，在沙门氏菌血清型伤寒沙门氏菌毒力质粒上发现了 bla(TEM-1) 基因，该基因通过电穿孔转移至大肠杆菌，并对两到四种其他抗菌药物具有耐药性。通过消减杂交和质粒分析进行的基因组分析表明，携带bla(TEM-1)的毒力质粒具有由不同来源的元件组成的嵌合结构。这些结果表明，日本北海道的牛中出现了一种携带毒力抗性质粒的新型多重耐药鼠伤寒沙门氏菌克隆。
The molecular epidemiology of 545 Salmonella enterica serovar Typhimurium isolates collected between 1977 and 2009 from cattle in Hokkaido, Japan, was investigated using pulsed-field gel electrophoresis (PFGE). Nine main clusters were identified from 116 PFGE patterns. Cluster I comprised 248 isolates, 243 of which possessed a sequence specific to definitive phage type 104 (DT104) or U302. The cluster I isolates were dominant in 1993 to 2003, but their numbers declined beginning in 2004. Beginning in 2002, an increase was observed in the number of cluster VII isolates, consisting of 21 PFGE patterns comprising 165 isolates. A total of 116 isolates representative of the 116 PFGE profiles were analyzed by multilocus variable-number tandem-repeat analysis (MLVA). Other than two drug-sensitive isolates, 19 isolates within cluster VII were classified in the same cluster by MLVA. Among the cluster VII isolates, an antibiotic resistance type showing resistance to ampicillin, chloramphenicol, streptomycin, sulfonamides, tetracycline, kanamycin, cefazolin, and sulfamethoxazole-trimethoprim and a resistance type showing resistance to ampicillin, streptomycin, sulfonamides, tetracycline, and kanamycin were found in 23 and 125 isolates, respectively. In the 19 isolates representative of cluster VII, the bla(TEM-1) gene was found on a Salmonella serotype Typhimurium virulence plasmid, which was transferred to Escherichia coli by electroporation along with resistance to two to four other antimicrobials. Genomic analysis by subtractive hybridization and plasmid analysis suggested that the bla(TEM-1)-carrying virulence plasmid has a mosaic structure composed of elements of different origin. These results indicate an emerging multidrug-resistant S. Typhimurium clone carrying a virulence-resistance plasmid among cattle in Hokkaido, Japan.