Xiaoyu Ruan , Wenji Wang , Dongguo Wang , Liman Ma
{"title":"携带药物外排泵和多个重复串联blaKPC-2核心结构的肺炎克雷伯菌临床多药耐药特征","authors":"Xiaoyu Ruan , Wenji Wang , Dongguo Wang , Liman Ma","doi":"10.1016/j.jiph.2025.102850","DOIUrl":null,"url":null,"abstract":"<div><h3>Objective</h3><div>To elucidate the mechanisms of multidrug resistance in clinical <em>Klebsiella pneumoniae</em> strains that harbor drug efflux pumps and contain multiple tandem repeats of the <em>bla</em><sub>KPC-2</sub> core structure.</div></div><div><h3>Methods</h3><div>The characteristics of strains SC7, SC35, SC38, SC41, SC42, SC67, and SC173 were comprehensively examined. This analysis encompassed antimicrobial susceptibility testing, conjugative transfer experiments, and the detection of beta-lactamase and carbapenemase production. The genomes of these strains were sequenced using both Illumina and Nanopore platforms to generate high-quality genomic data. Subsequently, bioinformatics tools were employed to analyze the mobile genetic elements that carry antibiotic resistance genes.</div></div><div><h3>Results</h3><div>The analyzed <em>K. pneumoniae</em> strains were found to produce class A carbapenemase and exhibited resistance to nearly all tested antibiotics. This resistance was primarily attributed to the presence of efflux pump genes, such as <em>acrAB-tolC</em>, located on the chromosomes. Additionally, these strains contained one or more repetitive tandem core structures of <em>bla</em><sub>KPC-2</sub>, as well as <em>bla</em><sub>KPC-2</sub> and/or <em>bla</em><sub>CTX-M-65</sub> core structures within their genomes. Some plasmids also harbored <em>bla</em><sub>SHV-12</sub>, <em>bla</em><sub>TEM-1</sub>, and <em>rmtB</em>. These genetic structures showed similarities to mobile genetic elements like Tn<em>3</em> and Tn<em>As3</em>. The identification of strain SC67, which possessed seven tandem repeats of the <em>bla</em><sub>KPC-2</sub> core structure, represents a novel finding and significantly advances our understanding of antibiotic resistance mechanisms. Plasmid transfer assays demonstrated successful conjugation in all strains, with varying average conjugation frequencies. Comparative analyses of the full-length plasmids and the multidrug resistance regions carrying <em>bla</em><sub>KPC-2</sub> and/or <em>bla</em><sub>CTX-M-65</sub> revealed a high degree of evolutionary conservation in these core structures.</div></div><div><h3>Conclusions</h3><div>The evolution of these strains is intricately linked to the core structures of <em>bla</em><sub>KPC-2</sub> and/or <em>bla</em><sub>CTX-M-65</sub>. Moreover, the presence of multiple drug efflux pumps on the chromosomes significantly contributes to their resistance to nearly all commonly used antibiotics. Given these findings, it is imperative to develop and implement effective strategies to curb the dissemination and prevalence of these highly resistant strains.</div></div>","PeriodicalId":16087,"journal":{"name":"Journal of Infection and Public Health","volume":"18 10","pages":"Article 102850"},"PeriodicalIF":4.7000,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Characterization of multidrug resistance in clinical Klebsiella pneumoniae strains carrying drug efflux pumps and multiple repetitive tandem blaKPC-2 core structures\",\"authors\":\"Xiaoyu Ruan , Wenji Wang , Dongguo Wang , Liman Ma\",\"doi\":\"10.1016/j.jiph.2025.102850\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><h3>Objective</h3><div>To elucidate the mechanisms of multidrug resistance in clinical <em>Klebsiella pneumoniae</em> strains that harbor drug efflux pumps and contain multiple tandem repeats of the <em>bla</em><sub>KPC-2</sub> core structure.</div></div><div><h3>Methods</h3><div>The characteristics of strains SC7, SC35, SC38, SC41, SC42, SC67, and SC173 were comprehensively examined. This analysis encompassed antimicrobial susceptibility testing, conjugative transfer experiments, and the detection of beta-lactamase and carbapenemase production. The genomes of these strains were sequenced using both Illumina and Nanopore platforms to generate high-quality genomic data. Subsequently, bioinformatics tools were employed to analyze the mobile genetic elements that carry antibiotic resistance genes.</div></div><div><h3>Results</h3><div>The analyzed <em>K. pneumoniae</em> strains were found to produce class A carbapenemase and exhibited resistance to nearly all tested antibiotics. This resistance was primarily attributed to the presence of efflux pump genes, such as <em>acrAB-tolC</em>, located on the chromosomes. Additionally, these strains contained one or more repetitive tandem core structures of <em>bla</em><sub>KPC-2</sub>, as well as <em>bla</em><sub>KPC-2</sub> and/or <em>bla</em><sub>CTX-M-65</sub> core structures within their genomes. Some plasmids also harbored <em>bla</em><sub>SHV-12</sub>, <em>bla</em><sub>TEM-1</sub>, and <em>rmtB</em>. These genetic structures showed similarities to mobile genetic elements like Tn<em>3</em> and Tn<em>As3</em>. The identification of strain SC67, which possessed seven tandem repeats of the <em>bla</em><sub>KPC-2</sub> core structure, represents a novel finding and significantly advances our understanding of antibiotic resistance mechanisms. Plasmid transfer assays demonstrated successful conjugation in all strains, with varying average conjugation frequencies. Comparative analyses of the full-length plasmids and the multidrug resistance regions carrying <em>bla</em><sub>KPC-2</sub> and/or <em>bla</em><sub>CTX-M-65</sub> revealed a high degree of evolutionary conservation in these core structures.</div></div><div><h3>Conclusions</h3><div>The evolution of these strains is intricately linked to the core structures of <em>bla</em><sub>KPC-2</sub> and/or <em>bla</em><sub>CTX-M-65</sub>. Moreover, the presence of multiple drug efflux pumps on the chromosomes significantly contributes to their resistance to nearly all commonly used antibiotics. Given these findings, it is imperative to develop and implement effective strategies to curb the dissemination and prevalence of these highly resistant strains.</div></div>\",\"PeriodicalId\":16087,\"journal\":{\"name\":\"Journal of Infection and Public Health\",\"volume\":\"18 10\",\"pages\":\"Article 102850\"},\"PeriodicalIF\":4.7000,\"publicationDate\":\"2025-06-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Infection and Public Health\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1876034125001996\",\"RegionNum\":3,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"INFECTIOUS DISEASES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Infection and Public Health","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1876034125001996","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
Characterization of multidrug resistance in clinical Klebsiella pneumoniae strains carrying drug efflux pumps and multiple repetitive tandem blaKPC-2 core structures
Objective
To elucidate the mechanisms of multidrug resistance in clinical Klebsiella pneumoniae strains that harbor drug efflux pumps and contain multiple tandem repeats of the blaKPC-2 core structure.
Methods
The characteristics of strains SC7, SC35, SC38, SC41, SC42, SC67, and SC173 were comprehensively examined. This analysis encompassed antimicrobial susceptibility testing, conjugative transfer experiments, and the detection of beta-lactamase and carbapenemase production. The genomes of these strains were sequenced using both Illumina and Nanopore platforms to generate high-quality genomic data. Subsequently, bioinformatics tools were employed to analyze the mobile genetic elements that carry antibiotic resistance genes.
Results
The analyzed K. pneumoniae strains were found to produce class A carbapenemase and exhibited resistance to nearly all tested antibiotics. This resistance was primarily attributed to the presence of efflux pump genes, such as acrAB-tolC, located on the chromosomes. Additionally, these strains contained one or more repetitive tandem core structures of blaKPC-2, as well as blaKPC-2 and/or blaCTX-M-65 core structures within their genomes. Some plasmids also harbored blaSHV-12, blaTEM-1, and rmtB. These genetic structures showed similarities to mobile genetic elements like Tn3 and TnAs3. The identification of strain SC67, which possessed seven tandem repeats of the blaKPC-2 core structure, represents a novel finding and significantly advances our understanding of antibiotic resistance mechanisms. Plasmid transfer assays demonstrated successful conjugation in all strains, with varying average conjugation frequencies. Comparative analyses of the full-length plasmids and the multidrug resistance regions carrying blaKPC-2 and/or blaCTX-M-65 revealed a high degree of evolutionary conservation in these core structures.
Conclusions
The evolution of these strains is intricately linked to the core structures of blaKPC-2 and/or blaCTX-M-65. Moreover, the presence of multiple drug efflux pumps on the chromosomes significantly contributes to their resistance to nearly all commonly used antibiotics. Given these findings, it is imperative to develop and implement effective strategies to curb the dissemination and prevalence of these highly resistant strains.
期刊介绍:
The Journal of Infection and Public Health, first official journal of the Saudi Arabian Ministry of National Guard Health Affairs, King Saud Bin Abdulaziz University for Health Sciences and the Saudi Association for Public Health, aims to be the foremost scientific, peer-reviewed journal encompassing infection prevention and control, microbiology, infectious diseases, public health and the application of healthcare epidemiology to the evaluation of health outcomes. The point of view of the journal is that infection and public health are closely intertwined and that advances in one area will have positive consequences on the other.
The journal will be useful to all health professionals who are partners in the management of patients with communicable diseases, keeping them up to date. The journal is proud to have an international and diverse editorial board that will assist and facilitate the publication of articles that reflect a global view on infection control and public health, as well as emphasizing our focus on supporting the needs of public health practitioners.
It is our aim to improve healthcare by reducing risk of infection and related adverse outcomes by critical review, selection, and dissemination of new and relevant information in the field of infection control, public health and infectious diseases in all healthcare settings and the community.