Laboratory of Antibiotics and Molecular Bacteriology, Department of Immunology, Microbiology and Parasitology, Faculty of Medicine and Nursing, University of the Basque Country, Leioa, Spain.
Microbiology Service, University Hospital Marqués de Valdecilla, Health Research Institute (IDIVAL), Santander, Spain.
Front Cell Infect Microbiol. 2024 Jan 9;13:1332736. doi: 10.3389/fcimb.2023.1332736. eCollection 2023.
Multidrug resistant is one of the most important nosocomial pathogens worldwide. During the last decades it has become a major threat for healthcare settings due to the high antibiotic resistance rates among these isolates. Many resistance determinants are coded by conjugative or mobilizable plasmids, facilitating their dissemination. The majority of plasmids harbored by species are less than 20 Kb, however, high molecular weight elements are the most clinically relevant since they usually contain antibiotic resistance genes. The aim of this work was to describe, classify and determine the genetic content of plasmids harbored by carbapem resistant isolates belonging to predominant clonal lineages circulating in hospitals from Alexandria, Egypt. The isolates were subjected to S1-Pulsed Field Gel Electrophoresis experiments to identify high molecular weight plasmids. To further analyze the plasmid content and the genetic localization of the antibiotic resistance genes, isolates were sequenced by Illumina Miseq and MinION Mk1C and a hybrid assembly was performed using Unicycler v0.5.0. Plasmids were detected with MOBsuite 3.0.3 and Copla.py v.1.0 and mapped using the online software Proksee.ca. Replicase genes were further analyzed through a BLAST against the Plasmid Typing database. Eleven plasmids ranging in size from 4.9 to 205.6 Kb were characterized and mapped. All isolates contained plasmids, and, in many cases, more than two elements were identified. Antimicrobial resistance genes such as , , and were found in likely conjugative large plasmids; while virulence determinants such as septicolysin or TonB-dependent receptors were identified in plasmids of small size. Some of these resistance determinants were, in turn, located within transposons and class 1 integrons. Among the identified plasmids, the majority encoded proteins belonging to the Rep_3 family, but replicases of the RepPriCT_1 (Aci6) family were also identified. Plasmids are of high interest as antibiotic resistance control tools, since they may be used as genetic markers for antibiotic resistance and virulence, and also as targets for the development of compounds that can inhibit transfer processes.
耐多药是全球最重要的医院病原体之一。在过去的几十年中，由于这些分离株的抗生素耐药率很高，它已成为医疗保健环境的主要威胁。许多耐药决定因素由可接合或可移动质粒编码，从而促进了它们的传播。 种属携带的大多数质粒小于 20 Kb，但是，高分子量元件是最具临床相关性的，因为它们通常包含抗生素耐药基因。本工作的目的是描述，分类和确定在埃及亚历山大医院流行的主要克隆谱系的耐碳青霉烯类 分离株中携带的质粒的遗传内容。对分离株进行 S1-脉冲场凝胶电泳实验以鉴定高分子量质粒。为了进一步分析质粒含量和抗生素耐药基因的遗传定位，使用 Illumina Miseq 和 MinION Mk1C 对分离株进行测序，并使用 Unicycler v0.5.0 进行混合组装。使用 MOBsuite 3.0.3 和 Copla.py v.1.0 检测质粒，并使用在线软件 Proksee.ca 进行映射。复制酶基因通过与质粒分型数据库的 BLAST 进一步分析。鉴定并映射了 11 个大小从 4.9 到 205.6 Kb 的质粒。所有分离株均携带质粒，在许多情况下，鉴定出超过两个元件。在可能的共轭大质粒中发现了抗生素耐药基因，如 、 、 和 ；而在小质粒中发现了毒力决定因素，如 Septiolyin 或 TonB 依赖性受体。这些耐药决定因素中的一些又位于转座子和 class 1 整合子内。在所鉴定的质粒中，大多数编码 Rep_3 家族的蛋白，但也鉴定了 RepPriCT_1（Aci6）家族的复制酶。由于质粒可作为抗生素耐药性和毒力的遗传标记，也可作为抑制转移过程的化合物的靶标，因此作为抗生素耐药性控制工具具有很高的意义。
