New Approach Methods to Assess the Enteropathogenic Potential of Strains of the Bacillus cereus Group, including Bacillus thuringiensis

Foods, Journal Year: 2024, Volume and Issue: 13(8), P. 1140 - 1140

Published: April 9, 2024

Bacillus cereus (Bc) is a wide group of Gram-positive and spore-forming bacteria, known to be the etiological agents various human infections, primarily food poisoning. The Bc includes enteropathogenic strains able germinate in digestive tract produce enterotoxins such as Nhe, Hbl, CytK. One species group, thuringiensis (Bt), has unique feature producing insecticidal crystals during sporulation, making it an important alternative chemical pesticides protect crops from insect pest larvae. Nevertheless, several studies have suggested link between ingestion pesticide cases poisoning, calling their safety into question. Consequently, reliable tools for virulence assessment are worth developing aid decision regulation. Here, we propose complementary approaches based on two biological models, intestinal Caco-2 cell line Drosophila melanogaster, assess rank enteric potency Bt comparison with other members. Using dataset 48 spp. strains, showed that some including Bt, were induce cytotoxicity cells concomitant release IL-8 cytokine, landmark pro-inflammatory response. In D. melanogaster model, sort panel 39 four different classes virulence, ranging no strong virulence. Importantly, most virulent mortality was associated loss barrier integrity. Interestingly, although can share common toxinotype, they display degrees suggesting existence specific mechanisms expression vivo intestine.

Language: Английский

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Corynebacterium diphtheriae Infections, South Africa, 2015–2023

Emerging infectious diseases, Journal Year: 2025, Volume and Issue: 31(3)

Published: Feb. 21, 2025

We reviewed Corynebacterium spp. infection cases reported in South Africa during 2015-2023. analyzed 84 isolates from 83 patients with C. diphtheriae, as well 1 belfantii and 3 ulcerans isolates. Among diphtheriae cases, we observed respiratory diphtheria (26/83 [31%]), endocarditis (14/83 [17%]), cutaneous (22/83 [27%]), nonspecific illnesses (5/83 [6%]), asymptomatic carriage (16/83 [19%]). The median patient age was 19 (range 0-88) years. Diphtheria-tetanus-pertussis vaccination incomplete for 26% (5/19) or unknown 68% (13/19) of children 0-9 years age. intermediately resistant to penicillin (82/84 [98%] isolates; MIC90 0.5 μg/mL) but susceptible erythromycin (83/84 [99%] 0.25 μg/mL). Eighteen unique sequence types were identified, corroborating heterogeneity. Toxin-producing strains detected among indicating all forms disease require monitoring prompt public health action curb transmission.

Language: Английский

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Early neonatal acquisition of extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales in Madagascar and Cambodia: clonal and plasmid-level contributions of maternal gut carriage

Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown

Published: April 15, 2025

Early neonatal infections caused by extended-spectrum-beta-lactamase-producing Enterobacterales (ESBL-PE) are prevalent in low- and middle-income countries, posing significant treatment challenges. This study investigated ESBL-PE colonization 499 mother-neonate pairs from Madagascar Cambodia, with stool samples collected at delivery neonates before day three. Using short- long-read sequencing, identical isolates or plasmids were identified within each pair to assess acquisition maternal source. Multinomial regression associated risk factors. Maternal gut carriage accounted for only 16.5% of acquisition, suggesting that most cases originated other sources. Primiparity wet season an increased the mother, while cesarean delivery, resuscitation, These findings challenge paradigm is primary source early colonization, highlighting need further research into alternative sources inform targeted interventions.

Language: Английский

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On the transformation of MinHash-based uncorrected distances into proper evolutionary distances for phylogenetic inference

F1000Research, Journal Year: 2020, Volume and Issue: 9, P. 1309 - 1309

Published: Nov. 10, 2020

Recently developed MinHash-based techniques were proven successful in quickly estimating the level of similarity between large nucleotide sequences. This article discusses their usage and limitations practice to approximating uncorrected distances genomes, transforming these pairwise dissimilarities into proper evolutionary distances. It is notably shown that complex distance measures can be easily approximated using simple transformation formulae based on few parameters. therefore very useful for implementing fast yet accurate alignment-free phylogenetic reconstruction procedures from sets genomes. last point view assessed with a simulation study dedicated bioinformatics tool.

Language: Английский

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The ZKIR Assay, a Real-Time PCR Method for the Detection of Klebsiella pneumoniae and Closely Related Species in Environmental Samples

Applied and Environmental Microbiology, Journal Year: 2020, Volume and Issue: 86(7)

Published: Jan. 29, 2020

The Klebsiella pneumoniae species complex Kp includes human and animal pathogens, some of which are emerging as hypervirulent and/or antibiotic-resistant strains. These pathogens diverse classified into seven phylogroups, may differ in their reservoirs epidemiology. Proper management this public health hazard requires a better understanding ecology routes transmission to humans. So far, detection these microorganisms matrices such food or the environment has been difficult due lack accurate sensitive methods. Here, we describe novel method based on real-time PCR enables all phylogroups with high sensitivity specificity. We used detect isolates from environmental samples, show genomic sequencing that they antimicrobial resistance virulence gene content clinical isolates. ZKIR assay will enable rapid screening multiple samples for presence thereby facilitate tracking dispersal patterns pathogenic strains across environmental, food, sources.

Language: Английский

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Accelerating the design of pili-enabled living materials using an integrative technological workflow

Nature Chemical Biology, Journal Year: 2023, Volume and Issue: 20(2), P. 201 - 210

Published: Nov. 27, 2023

Language: Английский

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Circulation of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli of Pandemic Sequence Types 131, 648, and 410 Among Hospitalized Patients, Caregivers, and the Community in Rwanda

Frontiers in Microbiology, Journal Year: 2021, Volume and Issue: 12

Published: May 14, 2021

Multi-drug resistant (MDR), gram-negative Enterobacteriaceae , such as Escherichia coli ( E. ) limit therapeutic options and increase morbidity, mortality, treatment costs worldwide. They pose a serious burden on healthcare systems, especially in developing countries like Rwanda. Several studies have shown the effects caused by global spread of extended-spectrum beta-lactamase (ESBL)-producing . However, limited data is available transmission dynamics these pathogens mobile elements they carry context clinical community locations Sub-Saharan Africa. Here, we examined 120 ESBL-producing strains from patients hospitalized University Teaching Hospital Butare (Rwanda), their attending caregivers well associated members livestock. Based whole-genome analysis, genetic diversification phylogenetics were assessed. Moreover, content carried plasmids was characterized investigated for putative among strains, potential role drivers antibiotic resistance. We show that 30 different sequence types (ST) detected pandemic clonal lineages ST131, ST648 ST410, which combine high-level antimicrobial resistance with virulence. In addition to frequently found genes bla CTX–M–15 tet (34), aph(6)-Id identified csg genes, are required curli fiber synthesis thus biofilm formation. Numerous harbored multiple virulence-associated (VAGs) including pap (P fimbriae adhesion cluster), fim (type I fimbriae) chu (Chu heme uptake system). Furthermore, phylogenetic relationships or related animals, indicates pathogens. Also, demonstrated presence transfer identical/similar ESBL-plasmids Rwandan setting when compared an external plasmid. This study highlights circulation clinically relevant, pathogenic patients, Combining virulence exchange bacterial poses significant risk around world.

Language: Английский

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Genomic Epidemiology and Strain Taxonomy of Corynebacterium diphtheriae

Journal of Clinical Microbiology, Journal Year: 2021, Volume and Issue: 59(12)

Published: Sept. 15, 2021

Corynebacterium diphtheriae is highly transmissible and can cause large diphtheria outbreaks where vaccination coverage insufficient. Sporadic cases or small clusters are observed in high-vaccination settings. The phylogeography short timescale evolution of C. not well understood, part due to a lack harmonized analytical approaches genomic surveillance strain tracking. We combined 1,305 genes with reproducible allele calls into core genome multilocus sequence typing (cgMLST) scheme. analyzed cgMLST gene diversity among 602 isolates from sporadic clinical cases, clusters, outbreaks. defined sublineages based on the phylogenetic structure within strains highest number mismatches documented performed time-scaled analyses major sublineages. scheme showed high call rate closely related species belfantii rouxii. demonstrate its utility delineate epidemiological case using 25 threshold reveal cryptic transmission chains, most which geographically restricted one few adjacent countries. Subcultures vaccine PW8 differed by up 20 mismatches. Phylogenetic revealed short-timescale evolutionary gain loss toxin biovar-associated genes. devised taxonomy deeper (defined 500-cgMLST-mismatch threshold), currently comprising 151 sublineages, only widespread current sampling. genotyping tool nomenclature was made publicly accessible (https://bigsdb.pasteur.fr/diphtheria). Standardized genome-scale will help tracing geographic spread diphtheriae. unified provides common language for studies ecology, evolution, virulence heterogeneity

Language: Английский

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Using Genomics To Investigate an Outbreak of Vancomycin-Resistant Enterococcus faecium ST78 at a Large Tertiary Hospital in Queensland

Microbiology Spectrum, Journal Year: 2023, Volume and Issue: 11(3)

Published: May 16, 2023

To investigate an outbreak of vancomycin-resistant Enterococcus faecium (VREfm) sequence type 78 (ST78) in a large tertiary Australian hospital. A collection 63 VREfm ST78 isolates, identified during routine genomic surveillance program, were subjected to epidemiological analysis based on whole-genome sequencing (WGS) data. The population structure was reconstructed using phylogenetic analysis, and publicly available genomes used provide global context. Core genome single nucleotide polymorphism (SNP) distances clinical metadata characterize clusters reconstruct transmission events. In silico genotyping confirmed that all study isolates vanB-type carrying virulence characteristics the hospital-associated E. faecium. Phylogenetic two distinct clades, only one which responsible for hospital outbreak. Four subtypes could be defined with examples recent transmissions. Inference trees suggested complex routes unknown environmental reservoirs mediating WGS-based cluster closely related ST203 highlighting capacity WGS resolve clonal relationships between lineages. Whole genome-based has provided high-resolution description Queensland Combined have facilitated better understanding local epidemiology this endemic strain, providing valuable insight targeted control VREfm. IMPORTANCE Vancomycin-resistant is leading cause health care-associated infections (HAIs) globally. Australia, spread hospital-adapted largely driven by group (clonal [CC]), CC17, lineage belongs. While implementing program Queensland, we observed increased incidence colonizations among patients. Here, demonstrate use real-time as tool support enhance infection (IC) practices. Our results show can efficiently disrupt outbreaks identifying turn resource-limited interventions. Additionally, placing context, high-risk clones prior them becoming established within environments. Finally, persistence these organism highlights need management VRE transmission.

Language: Английский

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Conserved bacterial genomes from two geographically isolated peritidal stromatolite formations shed light on potential functional guilds

Environmental Microbiology Reports, Journal Year: 2020, Volume and Issue: 13(2), P. 126 - 137

Published: Dec. 27, 2020

Stromatolites are complex microbial mats that form lithified layers. Fossilized stromatolites the oldest evidence of cellular life on Earth, dating back over 3.4 billion years. Modern relatively rare but may provide clues about function and evolution their ancient counterparts. In this study, we focus peritidal occurring at Cape Recife Schoenmakerskop southeastern South African coastline, former being morphologically structurally similar to fossilized phosphatic formations. Using assembled shotgun metagenomic analysis, obtained 183 genomic bins, which most dominant taxa were from Cyanobacteria phylum. We identified functional gene sets in bins conserved across two geographically isolated stromatolite formations, included high copy numbers genes involved reduction nitrates compounds. Additionally, found little Archaeal species these stromatolites, suggesting they not play an important role as proposed for hypersaline

Language: Английский

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