scholarly journals Genetic Characteristics and Microbiological Profile of Hypermucoviscous Multidrug-Resistant Klebsiella variicola Coproducing IMP-4 and NDM-1 Carbapenemases

2022 ◽  
Author(s):  
Bingjie Wang ◽  
Fen Pan ◽  
Dingding Han ◽  
Wantong Zhao ◽  
Yingying Shi ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Pediatric Patient ◽  
Multidrug Resistant ◽  
Human Pathogen ◽  
Genetic Characteristics ◽  
Content Type ◽  
Microbiological Profile ◽  
Important Member ◽  
First Time

As an important member of the Klebsiella pneumoniae complex, Klebsiella variicola is poorly studied as an emerging human pathogen. We, for the first time, report a unique K. variicola isolated from a pediatric patient in China.

scholarly journals KpnEF, a New Member of the Klebsiella pneumoniae Cell Envelope Stress Response Regulon, Is an SMR-Type Efflux Pump Involved in Broad-Spectrum Antimicrobial Resistance

2013 ◽  
Vol 57 (9) ◽  
pp. 4449-4462 ◽  
Author(s):  
Vijaya Bharathi Srinivasan ◽  
Govindan Rajamohan
Keyword(s):  
Klebsiella Pneumoniae ◽  
Efflux Pump ◽  
Cell Envelope ◽  
Sodium Dodecyl ◽  
Multidrug Resistant ◽  
Content Type ◽  
Enhanced Sensitivity ◽  
Envelope Stress ◽  
Phenotype Analysis ◽  
First Time

ABSTRACTKlebsiella pneumoniaehas been frequently associated with nosocomial infections. Efflux systems are ubiquitous transporters that also function in drug resistance. Genome analysis ofK. pneumoniaestrain NTUH-K2044 revealed the presence of ∼15 putative drug efflux systems. We discuss here for the first time the characterization of a putative SMR-type efflux pump, anebrABhomolog (denoted here askpnEF) with respect toKlebsiellaphysiology and the multidrug-resistant phenotype. Analysis of hypermucoviscosity revealed direct involvement ofkpnEFin capsule synthesis. The ΔkpnEFmutant displayed higher sensitivity to hyperosmotic (∼2.8-fold) and high bile (∼4.0-fold) concentrations. Mutation inkpnEFresulted in increased susceptibility to cefepime, ceftriaxone, colistin, erythromycin, rifampin, tetracycline, and streptomycin; mutated strains changed from being resistant to being susceptible, and the resistance was restored upon complementation. The ΔkpnEFmutant displayed enhanced sensitivity toward structurally related compounds such as sodium dodecyl sulfate, deoxycholate, and dyes, including clinically relevant disinfectants such as benzalkonium chloride, chlorhexidine, and triclosan. The prevalence ofkpnEFin clinical strains broadens the diversity of antibiotic resistance inK. pneumoniae. Experimental evidence of CpxR binding to the efflux pump promoter and quantification of its expression in acpxARmutant background demonstratedkpnEFto be a member of the Cpx regulon. This study helps to elucidate the unprecedented biological functions of the SMR-type efflux pump inKlebsiellaspp.

scholarly journals Draft Genome Sequence of Klebsiella pneumoniae OK8, a Multidrug-Resistant Mouse and Human Pathogen

2017 ◽  
Vol 5 (37) ◽  
Author(s):  
Easa Nagamalleswari ◽  
Valakunja Nagaraja
Keyword(s):  
Klebsiella Pneumoniae ◽  
Genome Sequence ◽  
Resistant Strain ◽  
Draft Genome ◽  
Multidrug Resistant ◽  
Draft Genome Sequence ◽  
Human Pathogen ◽  
Resistant Mouse ◽  
Content Type ◽  
Multidrug Resistant Strain

ABSTRACT We report here the draft genome sequence of Klebsiella pneumoniae OK8, a multidrug-resistant strain which was isolated in 1976 from a human and is known to be a mouse pathogen.

scholarly journals Genomic evolution and local epidemiology of Klebsiella pneumoniae from a major hospital in Beijing, China, over a 15 year period: dissemination of known and novel high-risk clones

2021 ◽  
Author(s):  
Mattia Palmieri ◽  
Kelly L. Wyres ◽  
Caroline Mirande ◽  
Zhao Qiang ◽  
Ye Liyan ◽  
...  
Keyword(s):  
High Risk ◽  
Klebsiella Pneumoniae ◽  
Type Species ◽  
Treatment Options ◽  
Multidrug Resistant ◽  
Virulence Plasmid ◽  
Content Type ◽  
Origin And Evolution ◽  
Link Type ◽  
Beijing China

Klebsiella pneumoniae is a frequent cause of nosocomial and severe community-acquired infections. Multidrug-resistant (MDR) and hypervirulent (hv) strains represent major threats, and tracking their emergence, evolution and the emerging convergence of MDR and hv traits is of major importance. We employed whole-genome sequencing (WGS) to study the evolution and epidemiology of a large longitudinal collection of clinical K. pneumoniae isolates from the H301 hospital in Beijing, China. Overall, the population was highly diverse, although some clones were predominant. Strains belonging to clonal group (CG) 258 were dominant, and represented the majority of carbapenemase-producers. While CG258 strains showed high diversity, one clone, ST11-KL47, represented the majority of isolates, and was highly associated with the KPC-2 carbapenemase and several virulence factors, including a virulence plasmid. The second dominant clone was CG23, which is the major hv clone globally. While it is usually susceptible to multiple antibiotics, we found some isolates harbouring MDR plasmids encoding for ESBLs and carbapenemases. We also reported the local emergence of a recently described high-risk clone, ST383. Conversely to strains belonging to CG258, which are usually associated to KPC-2, ST383 strains seem to readily acquire carbapenemases of different types. Moreover, we found several ST383 strains carrying the hypervirulence plasmid. Overall, we detected about 5 % of simultaneous carriage of AMR genes (ESBLs or carbapenemases) and hypervirulence genes. Tracking the emergence and evolution of such strains, causing severe infections with limited treatment options, is fundamental in order to understand their origin and evolution and to limit their spread. This article contains data hosted by Microreact.

scholarly journals Epigenomics, genomics, resistome, mobilome, virulome and evolutionary phylogenomics of carbapenem-resistant Klebsiella pneumoniae clinical strains

2020 ◽  
Vol 6 (12) ◽  
Author(s):  
Katlego Kopotsa ◽  
Nontombi M. Mbelle ◽  
John Osei Sekyere
Keyword(s):  
Klebsiella Pneumoniae ◽  
Multidrug Resistant ◽  
Type I ◽  
Bacteriophage Therapy ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Plasmid Replicon ◽  
Size Number ◽  
Plasmid Size ◽  
Epidemiological Trends

Carbapenem-resistant Klebsiella pneumoniae (CRKP) remains a major clinical pathogen and public health threat with few therapeutic options. The mobilome, resistome, methylome, virulome and phylogeography of CRKP in South Africa and globally were characterized. CRKP collected in 2018 were subjected to antimicrobial susceptibility testing, screening by multiplex PCR, genotyping by repetitive element palindromic (REP)-PCR, plasmid size, number, incompatibility and mobility analyses, and PacBio’s SMRT sequencing (n=6). There were 56 multidrug-resistant CRKP, having bla OXA-48-like and bla NDM-1/7 carbapenemases on self-transmissible IncF, A/C, IncL/M and IncX3 plasmids endowed with prophages, traT, resistance islands, and type I and II restriction modification systems (RMS). Plasmids and clades detected in this study were respectively related to globally established/disseminated plasmids clades/clones, evincing transboundary horizontal and vertical dissemination. Reduced susceptibility to colistin occurred in 23 strains. Common clones included ST307, ST607, ST17, ST39 and ST3559. IncFIIk virulent plasmid replicon was present in 56 strains. Whole-genome sequencing of six strains revealed least 41 virulence genes, extensive ompK36 mutations, and four different K- and O-loci types: KL2, KL25, KL27, KL102, O1, O2, O4 and O5. Types I, II and III RMS, conferring m6A (G A TC, G A TGNNNNNNTTG, CA A NNNNNNCATC motifs) and m4C (C C WGG) modifications on chromosomes and plasmids, were found. The nature of plasmid-mediated, clonal and multi-clonal dissemination of blaOXA-48-like and blaNDM-1 mirrors epidemiological trends observed for closely related plasmids and sequence types internationally. Worryingly, the presence of both bla OXA-48 and bla NDM-1 in the same isolates was observed. Plasmid-mediated transmission of RMS, virulome and prophages influence bacterial evolution, epidemiology, pathogenicity and resistance, threatening infection treatment. The influence of RMS on antimicrobial and bacteriophage therapy needs urgent investigation.

scholarly journals Complete Genome Sequence of Klebsiella pneumoniae Phage Sweeny

2019 ◽  
Vol 8 (39) ◽  
Author(s):  
Nicholas Martinez ◽  
Eric Williams ◽  
Heather Newkirk ◽  
Mei Liu ◽  
Jason J. Gill ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Complete Genome Sequence ◽  
Protein Level ◽  
Multidrug Resistant ◽  
Content Type ◽  
Hospital Acquired Infections ◽  
Multidrug Resistant Bacterium ◽  
Protein Encoding ◽  
Hospital Acquired ◽  
Encoding Genes

Klebsiella pneumoniae is a multidrug-resistant bacterium causing many severe hospital-acquired infections. Here, we describe siphophage Sweeny that infects K. pneumoniae. Of its 78 predicted protein-encoding genes, a functional assignment was given to 36 of them. Sweeny is most closely related to T1-like phages at the protein level.

scholarly journals Environmental Isolation of Candida auris from the Coastal Wetlands of Andaman Islands, India

mBio ◽  
2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Parth Arora ◽  
Prerna Singh ◽  
Yue Wang ◽  
Anamika Yadav ◽  
Kalpana Pawar ◽  
...  
Keyword(s):  
Salt Marsh ◽  
Coastal Wetlands ◽  
Ecological Niche ◽  
Multidrug Resistant ◽  
Sandy Beaches ◽  
Andaman Islands ◽  
Human Pathogen ◽  
Candida Auris ◽  
Content Type ◽  
The Indian Ocean

ABSTRACT Candida auris is a multidrug resistant pathogen that presents a serious global threat to human health. As C. auris is a newly emerged pathogen, several questions regarding its ecological niche remain unexplored. While species closely related to C. auris have been detected in different environmental habitats, little is known about the natural habitat(s) of C. auris. Here, we explored the virgin habitats around the very isolated Andaman Islands in the Indian Ocean for evidence of C. auris. We sampled coastal wetlands, including rocky shores, sandy beaches, tidal marshes, and mangrove swamps, around the Andaman group of the Andaman & Nicobar Islands, Union Territory, in India. Forty-eight samples of sediment soil and seawater were collected from eight sampling sites representing the heterogeneity of intertidal habitats across the east and west coast of South Andaman district. C. auris was isolated from two of the eight sampling sites, a salt marsh and a sandy beach. Interestingly, both multidrug-susceptible and multidrug-resistant C. auris isolates were found in the sample. Whole-genome sequencing analysis clustered the C. auris isolates into clade I, showing close similarity to other isolates from South Asia. Isolation of C. auris from the tropical coastal environment suggests its association with the marine ecosystem. The fact that viable C. auris was detected in the marine habitat confirms C. auris survival in harsh wetlands. However, the ecological significance of C. auris in salt marsh wetland and sandy beaches to human infections remains to be explored. IMPORTANCE Candida auris is a recently emerged multidrug-resistant fungal pathogen capable of causing severe infections in hospitalized patients. Despite its recognition as a human pathogen a decade ago, so far the natural ecological niche(s) of C. auris remains enigmatic. A previous hypothesis suggested that C. auris might be native to wetlands, that its emergence as a human pathogen might have been linked to global warming effects on wetlands, and that its enrichment in that ecological niche was favored by the ability of C. auris for thermal tolerance and salinity tolerance. To understand the mystery of environmental niches of C. auris, we explored the coastal wetland habitat around the very isolated Andaman Islands in the Indian Ocean. C. auris was isolated from the virgin habitats of salt marsh area with no human activity and from a sandy beach. C. auris isolation from the marine wetlands suggests that prior to its recognition as a human pathogen, it existed as an environmental fungus.

scholarly journals Draft Genome Sequences of Multidrug-Resistant Campylobacter jejuni Strains Isolated from Chickens in Central China

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Yiluo Cheng ◽  
Wenting Zhang ◽  
Qin Lu ◽  
Guoyuan Wen ◽  
Qingping Luo ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Antimicrobial Resistance ◽  
Campylobacter Jejuni ◽  
Draft Genome ◽  
Foodborne Pathogen ◽  
Multidrug Resistant ◽  
Central China ◽  
Genome Sequences ◽  
Genetic Characteristics ◽  
Content Type

Campylobacter jejuni is a major foodborne pathogen that plays an important role in spreading drug resistance. We report the draft genome sequences of two multidrug-resistant C. jejuni isolates which contained similar mutations in the CmeR box. This will improve the understanding of C. jejuni antimicrobial resistance and genetic characteristics.

scholarly journals Elucidating the Regulon of Multidrug Resistance Regulator RarA in Klebsiella pneumoniae

2013 ◽  
Vol 57 (4) ◽  
pp. 1603-1609 ◽  
Author(s):  
Shyamasree De Majumdar ◽  
Mark Veleba ◽  
Sarah Finn ◽  
Séamus Fanning ◽  
Thamarai Schneiders
Keyword(s):  
Klebsiella Pneumoniae ◽  
Cell Envelope ◽  
Polymyxin B ◽  
Multidrug Resistant ◽  
Protein Synthesis Inhibitors ◽  
Content Type ◽  
Phenotypic Microarray ◽  
Genes Encoding ◽  
Clusters Of Orthologous Groups ◽  
Microarray Analyses

ABSTRACTRarA is an AraC-type regulator inKlebsiella pneumoniae, which, when overexpressed, confers a low-level multidrug-resistant (MDR) phenotype linked to the upregulation of both theacrABandoqxABefflux genes. IncreasedrarAexpression has also been shown to be integral in the development of tigecycline resistance in the absence oframAinK. pneumoniae. Given its phenotypic role in MDR, microarray analyses were performed to determine the RarA regulon. Transcriptome analysis was undertaken using strains Ecl8ΔrarA/pACrarA-2 (rarA-expressing construct) and Ecl8ΔrarA/pACYC184 (vector-only control) using bespoke microarray slides consisting of probes derived from the genomic sequences ofK. pneumoniaeMGH 78578 (NC_009648.1) and Kp342 (NC_011283.1). Our results show thatrarAoverexpression resulted in the differential expression of 66 genes (42 upregulated and 24 downregulated). Under the COG (clusters of orthologous groups) functional classification, the majority of affected genes belonged to the category of cell envelope biogenesis and posttranslational modification, along with genes encoding the previously uncharacterized transport proteins (e.g., KPN_03141,sdaCB, andleuE) and the porin OmpF. However, genes associated with energy production and conversion and amino acid transport/metabolism (e.g.,nuoA,narJ, andproWX) were found to be downregulated. Biolog phenotype analyses demonstrated thatrarAoverexpression confers enhanced growth of the overexpresser in the presence of several antibiotic classes (i.e., beta-lactams and fluoroquinolones), the antifungal/antiprotozoal compound clioquinol, disinfectants (8-hydroxyquinoline), protein synthesis inhibitors (i.e., minocycline and puromycin), membrane biogenesis agents (polymyxin B and amitriptyline), DNA synthesis (furaltadone), and the cytokinesis inhibitor (sanguinarine). Both our transcriptome and phenotypic microarray data support and extend the role of RarA in the MDR phenotype ofK. pneumoniae.

scholarly journals Fighting Antibiotic-Resistant Klebsiella pneumoniae with “Sweet” Immune Targets

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Roberto Adamo ◽  
Immaculada Margarit
Keyword(s):  
Klebsiella Pneumoniae ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Therapeutic Approaches ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Surface Polysaccharides ◽  
Resistant Strains ◽  
Murine Monoclonal Antibodies

ABSTRACT Antibiotics and vaccines have greatly impacted human health in the last century by dramatically reducing the morbidity and mortality associated with infectious diseases. The recent challenge posed by the emergence of multidrug-resistant bacteria could possibly be addressed by novel immune prophylactic and therapeutic approaches. Among the newly threatening pathogens, Klebsiella pneumoniae is particularly worrisome in the nosocomial setting, and its surface polysaccharides are regarded as promising antigen candidates. The majority of Klebsiella carbapenem-resistant strains belong to the sequence type 158 (ST258) lineage, with two main clades expressing capsular polysaccharides CPS1 and CPS2. In a recent article, S. D. Kobayashi and colleagues (mBio 9:e00297-18, 2018, https://doi.org/10.1128/mBio.00297-18) show that CPS2-specific IgGs render ST258 clade 2 bacteria more sensitive to human serum and phagocytic killing. E. Diago-Navarro et al. (mBio 9:e00091-18, 2018, https://doi.org/10.1128/mBio.00091-18) generated two murine monoclonal antibodies recognizing distinct glycotopes of CPS2 that presented functional activity against multiple ST258 strains. These complementary studies represent a step toward the control of this dangerous pathogen.

scholarly journals Complete Genome Sequence of Klebsiella pneumoniae Strain TK421, a Conjugative Hypervirulent Isolate

2020 ◽  
Vol 9 (3) ◽  
Author(s):  
Travis J. Kochan ◽  
Egon A. Ozer ◽  
Nathan B. Pincus ◽  
Margaret A. Fitzpatrick ◽  
Alan R. Hauser
Keyword(s):  
Klebsiella Pneumoniae ◽  
Genome Sequence ◽  
Nosocomial Infections ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Multidrug Resistant ◽  
Negative Bacterium ◽  
Gram Negative ◽  
Content Type ◽  
Rapid Dissemination

Klebsiella pneumoniae is a Gram-negative bacterium that is a major cause of nosocomial infections worldwide. Here, we present the complete genome sequence of TK421, a clinical bacteremia isolate containing a hypervirulence plasmid carrying tra-associated conjugation machinery genes. Emergence of conjugative hypervirulence plasmids could portend rapid dissemination of hypervirulence among multidrug-resistant K. pneumoniae strains.

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