Characterization of plasmids mediating carbapenem resistance in Klebsiella pneumoniae in Pretoria, South Africa

The study aimed to characterize plasmids mediating carbepenem resistance in Klebsiella pneumoniae in Pretoria, South Africa. We analysed 56 K. pneumoniae isolates collected from academic hospital around Pretoria. Based on phenotypic and molecular results of these isolates, 6 representative isolates were chosen for further analysis using long reads sequencing platform. We observed multidrug resistant phenotype in all these isolates, including resistance to aminoglycosides, tetracycline, phenicol, fosfomycin, floroquinolones, and beta-lactams antibiotics. The blaOXA-48/181 and blaNDM-1/7 were manily the plasmid-mediated carbapenemases responsible for carbapenem resistance in the K. pneumoniae isolates in these academic hospitals. These carbapenemase genes were mainly associated with plasmid replicon groups IncF, IncL/M, IncA/C, and IncX3. This study showed plasmid-mediated carbapenemase spread of blaOXA and blaNDM genes mediated by conjugative plasmids in Pretoria hospitals. Six carbapenem-resistant K. pneumoniae isolates were sequenced using PacBio sequencer; PRJNA565241

本研究旨在表征南非比勒陀利亚地区肺炎克雷伯菌（Klebsiella pneumoniae）中介导碳青霉烯类耐药的质粒。我们分析了从比勒陀利亚周边教学医院采集的56株肺炎克雷伯菌分离株。基于这些分离株的表型与分子检测结果，选取6株代表性分离株，采用长读长测序平台开展后续分析。所有上述分离株均呈现多重耐药表型，对氨基糖苷类、四环素类、酰胺醇类、磷霉素、氟喹诺酮类及β-内酰胺类抗生素均具有耐药性。blaOXA-48/181与blaNDM-1/7是本研究中该地区教学医院肺炎克雷伯菌分离株碳青霉烯类耐药的主要质粒介导碳青霉烯酶。上述碳青霉烯酶基因主要与IncF、IncL/M、IncA/C及IncX3型质粒复制子家族相关。本研究证实，比勒陀利亚地区医院内blaOXA与blaNDM基因可通过接合性质粒实现质粒介导的碳青霉烯酶传播。本研究采用PacBio测序平台对6株碳青霉烯类耐药肺炎克雷伯菌分离株进行测序，相关测序数据的BioProject编号为PRJNA565241