Universidade do Estado do Rio de Janeiro, Faculdade de Ciências Médicas, Departamento de Microbiologia, Imunologia e Parasitologia, Brasil. Blv. 28 de Setembro, 87 fundos 3º andar, 20550-170, Vila Isabel, Rio de Janeiro, Brazil; University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Hanzeplein 1, 9713GZ, Groningen, The Netherlands.
University of Groningen, University Medical Center Groningen, Department of Medical Microbiology and Infection Prevention, Hanzeplein 1, 9713GZ, Groningen, The Netherlands.
Int J Med Microbiol. 2020 Dec;310(8):151453. doi: 10.1016/j.ijmm.2020.151453. Epub 2020 Sep 28.
Extraintestinal pathogenic E. coli (ExPEC) is the most frequent etiological agent of urinary tract infections (UTIs). Particular evolutionary successful lineages are associated with severe UTIs and higher incidences of multidrug resistance. Most of the resistance genes are acquired by horizontal transfer of plasmids and other mobile genetic elements (MGEs), and this process has been associated with the successful dissemination of particular lineages. Here, we identified the presence of MGEs and their role in virulence and resistance profiles of isolates obtained from the urine of hospitalized patients in Brazil. Isolates belonging to the successful evolutionary lineages of sequence type (ST) 131, ST405, and ST648 were found to be multidrug-resistant, while those belonging to ST69 and ST73 were often not. Among the ST131, ST405, and ST648 isolates with a resistant phenotype, a high number of mainly IncFII plasmids was identified. The plasmids contained resistance cassettes, and these were also found within phage-related sequences and the chromosome of the isolates. The resistance cassettes were found to harbor several resistance genes, including bla. In addition, in ST131 isolates, diverse pathogenicity islands similar to those found in highly virulent ST73 isolates were detected. Also, a new genomic island associated with several virulence genes was identified in ST69 and ST131 isolates. In addition, several other MGEs present in the ST131 reference strain EC958 were identified in our isolates, most of them exclusively in ST131 isolates. In contrast, genomic islands present in this reference strain were only partially present or completely absent in our ST131 isolates. Of all isolates studied, ST73 and ST131 isolates had the most similar virulence profile. Overall, no clear association was found between the presence of specific MGEs and virulence profiles. Furthermore, the interplay between virulence and resistance by acquiring MGEs seemed to be lineage dependent. Although the acquisition of IncF plasmids, specific PAIs, GIs, and other MGEs seemed to be involved in the success of some lineages, it cannot explain the success of different lineages, also indicating other (host) factors are involved in this process. Nevertheless, the detection, identification, and surveillance of lineage-specific MGEs may be useful to monitor (new) emerging clones.
肠外致病性大肠杆菌（ExPEC）是尿路感染（UTI）最常见的病原体。特定的进化成功谱系与严重的 UTI 和更高的多药耐药发生率有关。大多数耐药基因是通过质粒和其他移动遗传元件（MGE）的水平转移获得的，这一过程与特定谱系的成功传播有关。在这里，我们确定了 MGE 的存在及其在巴西住院患者尿液分离株的毒力和耐药谱中的作用。属于序列型（ST）131、ST405 和 ST648 成功进化谱系的分离株被发现是多药耐药的，而属于 ST69 和 ST73 的分离株则常常不是。在具有耐药表型的 ST131、ST405 和 ST648 分离株中，发现了大量主要的 IncFII 质粒。这些质粒含有耐药盒，这些耐药盒也存在于噬菌体相关序列和分离株的染色体中。耐药盒中发现了多种耐药基因，包括 bla。此外，在 ST131 分离株中，还检测到与高度毒力 ST73 分离株中发现的相似的多种致病性岛。此外，在 ST69 和 ST131 分离株中还发现了一个与多个毒力基因相关的新基因组岛。此外，在我们的分离株中还发现了 ST131 参考菌株 EC958 中存在的其他几种 MGE，其中大多数仅存在于 ST131 分离株中。相比之下，在我们的 ST131 分离株中，参考菌株中存在的基因组岛要么完全缺失，要么只有部分存在。在所研究的所有分离株中，ST73 和 ST131 分离株的毒力谱最相似。总体而言，特定 MGE 的存在与毒力谱之间没有明显的关联。此外，通过获得 MGE 来调节毒力和耐药性似乎依赖于谱系。尽管 IncF 质粒、特定的 PAIs、GIs 和其他 MGE 的获得似乎与一些谱系的成功有关，但这并不能解释不同谱系的成功，也表明其他（宿主）因素也参与了这一过程。然而，检测、鉴定和监测谱系特异性 MGE 可能有助于监测（新）出现的克隆。
