CTX-M-1 and CTX-M-15-producing Escherichia coli in dog faeces from public gardens.
CTX-M-1 and CTX-M-15-producing Escherichia coli in dog faeces from public gardens.
复制标题
DOI：
10.1186/s13028-015-0174-3
复制
发表时间：
2015-11-25
影响因子：
2.1
通讯作者：
Guardabassi L
中科院分区：
文献类型：
--
作者：
Damborg P;Morsing MK;Petersen T;Bortolaia V;Guardabassi L
产生广谱β -内酰胺酶（ESBL）的大肠杆菌在狗身上的报道越来越多。本研究的目的是提供有关公共花园中狗粪便沉积物中产生esbl的大肠杆菌的流行情况的数据。在丹麦哥本哈根的9个公共花园收集了209个粪便沉积物，通过选择性富集，然后在添加头孢噻肟的麦康基琼脂上电镀，对其进行筛选。采用MALDI-TOF质谱法和聚合酶链反应（PCR）检测常见头孢噻肟耐药决定因子（blaTEM、blaSHV、blaCTX-M和blaCMY-2），证实可能产生esbl的大肠杆菌。采用多位点序列分型（MLST）和微量肉汤稀释法进行抗菌药敏试验。通过S1核酸酶脉冲场凝胶电泳、pcr复制子分型和pMLST对携带ESBL基因的质粒进行了表征。4份（1.9%）样品检出头孢噻肟耐药大肠杆菌。三个样品中含有产生ctx - m -1的分离株，一个样品中含有两个产生ctx - m -15的分离株，表现出不同的菌落形态。所有分离株都属于不同的序列类型（STs），包括一个以前与人类特异性病原型相关的大肠杆菌谱系（ST59）。blaCTX-M-1携带于经pMLST分类为ST3或ST58的IncI1质粒上，而blaCTX-M-15携带于同一样品分离的两株菌株的IncF/Y质粒和不可分型质粒上。该研究表明，狗粪便是城市地区产生ctx - m的大肠杆菌传播的媒介。人类在公众花园接触狗屎所产生的风险，取决于这些细菌在本地狗群中的流行程度，以及狗主人清除和处置狗屎的做法。
Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli are increasingly reported in dogs. The objective of this study was to provide data on the prevalence of ESBL-producing E. coli in dog faecal deposits in public gardens. A total of 209 faecal deposits collected in nine public gardens in Copenhagen, Denmark were screened by selective enrichment followed by plating on MacConkey agar supplemented with cefotaxime. Presumptive ESBL-producing E. coli were confirmed by MALDI-TOF MS and polymerase chain reaction (PCR) for detection of common cefotaxime resistance determinants (blaTEM, blaSHV, blaCTX-M and blaCMY-2). ESBL-producers were further characterized by multilocus sequence typing (MLST) and antimicrobial susceptibility testing using broth microdilution. Plasmids harbouring ESBL genes were characterized by S1 nuclease pulsed field gel electrophoresis, PCR-based replicon typing, and pMLST. Cefotaxime-resistant E. coli were detected in four (1.9 %) samples. Three samples harboured CTX-M-1-producing isolates, and one sample contained two CTX-M-15-producing isolates displaying distinct colony morphology. All isolates belonged to distinct sequence types (STs), including one E. coli lineage previously associated to a human-specific pathotype (ST59). blaCTX-M-1 was carried on IncI1 plasmids classified as ST3 or ST58 by pMLST, whereas blaCTX-M-15 was located on IncF/Y and non-typeable plasmids in the two strains isolated from the same sample. The study shows that dog faeces are a vector for dissemination of CTX-M-producing E. coli within urban areas. The risk derived from human exposure to dog faeces in public gardens depends on the prevalence of these bacteria in the local dog population as well as on the owners’ practice to remove and dispose their dog’s faeces.