National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
Public Health Agency of Canada, Ottawa, Ontario, Canada.
Microb Genom. 2024 Jun;10(6). doi: 10.1099/mgen.0.001257.
Carbapenems are last-resort antibiotics for treatment of infections caused by multidrug-resistant , but carbapenem resistance is a rising global threat due to the acquisition of carbapenemase genes. Oxacillinase-48 ( )-type carbapenemases are increasing in abundance in Canada and elsewhere; these genes are frequently found on mobile genetic elements and are associated with specific transposons. This means that alongside clonal dissemination, genes can spread through plasmid-mediated horizontal gene transfer. We applied whole genome sequencing to characterize 249 -producing isolates collected by the Canadian Nosocomial Infection Surveillance Program from 2010 to 2021. Using a combination of short- and long-read sequencing, we obtained 70 complete and circular -encoding plasmids. Using MOB-suite, four major plasmids clustered were identified, and we further estimated a plasmid cluster for 91.9 % (147/160) of incomplete -encoding contigs. We identified different patterns of carbapenemase mobilization across Canada, including horizontal transmission of /IncX3 plasmids (75/249, 30.1 %) and /IncL/M plasmids (47/249, 18.9 %), and both horizontal transmission and clonal transmission of for ST231 on ColE2-type/ColKP3 plasmids (25/249, 10.0 %). Our findings highlight the diversity of OXA-48-type plasmids and indicate that multiple plasmid clusters and clonal transmission have contributed to spread and persistence in Canada.
碳青霉烯类抗生素是治疗多重耐药菌感染的最后手段，但由于获得碳青霉烯酶基因，碳青霉烯类抗生素的耐药性已成为全球日益严重的威胁。在加拿大和其他地方，耐碳青霉烯酶 48 型（OXA-48）- 型碳青霉烯酶的数量正在增加；这些基因通常存在于移动遗传元件上，并与特定的转座子相关。这意味着，除了克隆传播外， blaOXA-48 基因还可以通过质粒介导的水平基因转移传播。我们应用全基因组测序技术对加拿大医院感染监测计划（Canadian Nosocomial Infection Surveillance Program）于 2010 年至 2021 年期间收集的 249 株产 blaOXA-48 基因的分离株进行了特征分析。通过短读长和长读长测序的结合，我们获得了 70 个完整且环状的 blaOXA-48 基因编码质粒。使用 MOB-suite 软件，我们确定了 4 个主要的质粒簇，并进一步估计了 91.9%（147/160）不完整 blaOXA-48 基因编码序列的质粒簇。我们在加拿大各地发现了不同的碳青霉烯酶转移模式，包括 blaOXA-48/IncX3 质粒（75/249，30.1%）和 blaOXA-48/IncL/M 质粒（47/249，18.9%）的水平传播，以及 blaOXA-48 基因在 ST231 上的 ColE2 型/ColKP3 质粒上的水平传播和克隆传播（25/249，10.0%）。我们的研究结果突出了 OXA-48 型质粒的多样性，并表明多个质粒簇和克隆传播导致了 blaOXA-48 基因在加拿大的传播和持续存在。
