Clinical and laboratory insights into the threat of hypervirulent Klebsiella pneumoniae

International Journal of Antimicrobial Agents, Journal Year: 2024, Volume and Issue: 64(3), P. 107275 - 107275

Published: July 14, 2024

Language: Английский

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Bacteriogenic synthesis of morphologically diverse silver nanoparticles and their assessment for methyl orange dye removal and antimicrobial activity

PeerJ, Journal Year: 2024, Volume and Issue: 12, P. e17328 - e17328

Published: May 17, 2024

Nanotechnology and nanoparticles have gained massive attention in the scientific community recent years due to their valuable properties. Among various AgNPs synthesis methods, microbial approaches offer distinct advantages terms of cost-effectiveness, biocompatibility, eco-friendliness. In present research work, investigators synthesized three different types silver (AgNPs), namely AgNPs-K, AgNPs-M, AgNPs-E, by using Klebsiella pneumoniae (MBC34), Micrococcus luteus (MBC23), Enterobacter aerogenes (MBX6), respectively. The morphological, chemical, elemental features were analyzed UV-Vis spectroscopy (UV-Vis), Fourier transform-infrared (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) energy-dispersive (EDX). absorbance peaks obtained at 475, 428, 503 nm for XRD analysis confirmed crystalline nature AgNPs, having 26.2°, 32.1°, 47.2°. At same time, FTIR showed bands 599, 963, 1,693, 2,299, 2,891, 3,780 cm −1 all indicating presence bacterial biomolecules with developed AgNPs. size morphology varied from 10 several microns exhibited spherical porous sheets-like structures. percentage Ag 37.8% (wt.%) 61.6%, i.e ., highest AgNPs-K lowest AgNPs-M. Furthermore, potential environmental remediation, AgNPs-M exhibiting removal efficiency (19.24% 120 min) methyl orange dye simulated wastewater. Further, evaluated wastewater, where was 19.24% min Antibacterial assessment against both Gram-positive (GPB) Bacillus subtilis B. cereus (MBC24), Gram-negative bacteria Enterococcus faecalis (MBP13) revealed promising results, largest zone inhibition (12 mm) GPB megaterium . Such investigation exhibits diverse applications remediation antibacterial therapy-based

Language: Английский

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The type VI secretion system as a potential predictor of subsequent bloodstream infection of carbapenem-resistant Klebsiella pneumoniae strains on intestinal colonization

Infection, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 3, 2025

Language: Английский

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Comprehensive genomic epidemiology and antimicrobial resistance profiles of clinical Klebsiella pneumoniae species complex isolates from a tertiary hospital in Wenzhou, China (2019–2021)

BMC Genomics, Journal Year: 2025, Volume and Issue: 26(1)

Published: March 31, 2025

The main issue of the Klebsiella pneumoniae species complex (KpSC) research in clinical settings is accurate identification and differentiation closely related within this complex. Moreover, emergence spread carbapenem-resistant K. (CRKP) represent a significant public health threat due to limited treatment options high mortality rates. Understanding genetic basis resistance virulence crucial for developing effective infection control strategies. In work, genomic epidemiology antimicrobial profile KpSC isolates from Wenzhou, China, was investigated fully understand implications settings. We conducted comprehensive analysis 156 collected tertiary hospital China over three-year period (2019–2021). Antimicrobial susceptibility testing performed according CLSI standards. Whole-genome sequencing (WGS) subsequent bioinformatic analyses were identify genes, plasmid types, factors. Phylogenetic relationships determined using maximum-likelihood analysis. All CRKP exhibited levels carbapenems, cephalosporins, aminoglycosides. most prevalent carbapenemase genes blaKPC−2 (100%), with associations between ST11. revealed considerable diversity, 50 sequence types (STs) present. A subset harbored both hypervirulence including rmpA, rmpA2, siderophore systems, which associated potential higher pathogenesis. This study provides novel insights into molecular highlighting coexistence factors isolates. findings underscore importance continuous surveillance targeted therapeutic strategies combat infections. Our fills critical gaps current understanding offers valuable data global comparative studies, contributing development measures. Genomic thus local risk mapping informs necessary adaptions implementation

Language: Английский

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Comparative Genomic Profiles of Salmonella Typhimurium and Salmonella Dublin Bovine Isolates from the U.S. Indicate Possible Factors Associated with the Host Adaptation of Salmonella Dublin in the Region

Microorganisms, Journal Year: 2025, Volume and Issue: 13(4), P. 886 - 886

Published: April 12, 2025

Salmonella Dublin (S. Dublin) and Typhimurium Typhimurium) are commonly linked to bovine salmonellosis. S. is, however, considered a bovine-adapted serovar for primarily infecting thriving in cattle. Using (a generalist serovar) as benchmark, this study investigates genomic factors contributing Dublin’s adaptation cattle hosts the U.S. A total of 1337 787 whole-genome sequences from sources were analyzed with CARD (version 4.0.0), ARG-NOTT 6), AMRfinderPlus 4.0.3) antimicrobial resistance (AMR) genes; VFDB virulence AMRFinderPlus stress Plasmidfinder plasmids. Existing clonal groups among isolates two serovars also investigated using Hierarchical Clustering Core Genome Multi-Locus Sequence Typing (HierCC-cgMLST) model. The results revealed minimal variation isolates. Comparatively, IncX1 plasmid was somewhat exclusively identified each carried an average four plasmids (p-value < 0.05). Furthermore, exhibited higher prevalence AMR genes against key antimicrobials, including aminoglycosides, beta-lactams, tetracyclines, sulfonamides, used production. Additionally, Type VI secretion system tssJKLM hcp2/tssD2, essential colonization, found over 50% these possessing that confer heavy metal stressors, like mercury. These findings suggest is supported by conserved genetic makeup enriched genes, factors, stress-related enabling it colonize persist gut.

Language: Английский

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Klebsiella pneumoniae employs a type VI secretion system to overcome microbiota-mediated colonization resistance

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 22, 2025

Microbial species must compete for space and nutrients to persist in the gastrointestinal (GI) tract, our understanding of complex pathobiont-microbiota interactions is far from complete. Klebsiella pneumoniae, a problematic, often drug-resistant nosocomial pathogen, can colonize GI tract asymptomatically, serving as an infection reservoir. To provide insight on how K. pneumoniae interacts with resident gut microbiome, we conduct transposon mutagenesis screen using murine model colonization intact microbiota. Among genes identified were those encoding type VI secretion system (T6SS), which mediates contact-dependent killing gram-negative bacteria. From several approaches, demonstrate that T6SS critical colonization. Metagenomics vitro assays reveal reduces Betaproteobacteria T6SS-dependent manner, thus identifying specific targeted by pneumoniae. We further show gene expression controlled transcriptional regulators only occurs under conditions mimic environment. By enabling thrive gut, indirectly contributes pathogenic potential this organism. These observations advance molecular successfully colonizes tract. Through metagenomics, Bray et al. interacting microbiota partners revealed role its colonization, t6ss transcription occurring GI-mimetic conditions.

Language: Английский

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Genome-wide screens reveal shared and strain-specific genes that facilitate enteric colonization by Klebsiella pneumoniae

mBio, Journal Year: 2023, Volume and Issue: 14(6)

Published: Oct. 25, 2023

is a common cause of difficult-to-treat infections due to its propensity express resistance many antibiotics. For example, carbapenem-resistant

Language: Английский

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Deciphering the gastrointestinal carriage of Klebsiella pneumoniae

Infection and Immunity, Journal Year: 2024, Volume and Issue: 92(9)

Published: April 10, 2024

ABSTRACT Bacterial infections pose a significant global health threat, accounting for an estimated 7.7 million deaths. Hospital outbreaks driven by multi-drug-resistant pathogens, notably Klebsiella pneumoniae ( K. ), are of grave concern. This opportunistic pathogen causes pneumonia, urinary tract infections, and bacteremia, particularly in immunocompromised individuals. The rise hypervirulent adds complexity, as it increasingly infects healthy Recent epidemiological data suggest that asymptomatic gastrointestinal carriage serves reservoir the same individual allows host-to-host transmission via fecal-oral route. review focuses on ’s colonization, delving into evidence, current animal models, molecular colonization mechanisms, protective role resident gut microbiota. Moreover, sheds light vivo high-throughput approaches have been crucial identifying factors colonization. comprehensive exploration aims to enhance our understanding pathogenesis, guiding future intervention prevention strategies.

Language: Английский

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The Biological and Regulatory Role of Type VI Secretion System of Klebsiella pneumoniae

Infection and Drug Resistance, Journal Year: 2023, Volume and Issue: Volume 16, P. 6911 - 6922

Published: Oct. 1, 2023

Abstract: Bacteria communicate with their surroundings through diverse secretory systems, and the recently discovered Type VI Secretion System (T6SS) has gained significant attention. Klebsiella pneumoniae (K. pneumoniae) , an opportunistic pathogen known for causing severe infections in both hospital animal settings, possesses this intriguing T6SS. This system equips K. a formidable armory of protein-based weaponry, enabling delivery toxins into neighboring cells, thus granting substantial competitive advantage. Remarkably, T6SS also been associated pneumoniae’s ability to form biofilms acquire resistance against antibiotics. However, precise effects on functions remain inadequately studied, despite research efforts understand intricacies these mechanisms. comprehensive review aims provide overview current knowledge regarding biological regulatory mechanisms pneumoniae. Keywords: T6SS, competition, drug resistance, virulence

Language: Английский

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Molecular insights into novel environmental strains of Klebsiella quasipneumoniae harboring different antimicrobial-resistance genes

Frontiers in Public Health, Journal Year: 2023, Volume and Issue: 10

Published: Jan. 12, 2023

Introduction The emergence of bacterial pathogens in environmental hosts represents a major risk to public health. This study aimed at characterizing seven novel strains K. quasipneumoniae using genomic approach which was misidentified by phenotypic methods previous batch 27 species thought be pneumoniae . Methods Whole-genome sequencing performed the Illumina platform, and generated raw reads were de novo assembled. Comparative genomic, resistome, virulome, mobilome, phylogeny then investigated dierent bioinformatics tools. Results Six identified as subsp similipneumoniae one subsp. All isolates resistant ampicillin, cephalexin, amoxicillin-clavulanic acid harbored fosA , bla OKP types, oqxB oqxA genes. One isolate additionally gene cassettes consisting SHV−1 OXA−1 aac(6 ′ )-Ib-cr, catB aminoglycoside-modifying enzyme aph(3”)-Ia bracketed two insertion elements. Plasmid analyses showed that IncFIB K most prevalent plasmid, circulating six isolates, while exhibited different plasmids. have virulence genes responsible for capsule formation, lipopolysaccharide, iron uptake aerobactin ( iutA ), salmochelins iroE, iroN enterobactin siderophore, adherence, biofilm formation mrkA, mrkB, mrkC, mrkD, mrkF mrkH ). Conclusion Our highlights ecology transmission (which ability disseminate other sources including animals) outside clinical setting contribution water, vegetables, table surfaces potential reservoirs farm-to-fork disease via local markets Khartoum, Sudan.

Language: Английский

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