Optimization of the Amoeba Plate Test for the Isolation of Legionella and Other Opportunistic Pathogens from Environmental Water Samples DOI
Anaísa B. Moreno, Tong Chen,

Yasemin Gökuguz

et al.

ACS ES&T Water, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 5, 2024

Free-living amoebae represent a reservoir for some environmental bacteria that are opportunistic human pathogens. Legionella pneumophila is Gram-negative, amoeba-resistant bacterium, which upon inhalation can cause life-threatening atypical pneumonia termed Legionnaires' disease. The capacity to grow within and other protozoa prerequisite L. virulence requires the bacterial Icm/Dot type IV secretion system (T4SS). plate test (APT) exploits of virulent rather than Icm/Dot-deficient on BCYE agar plates in presence amoeba. Here, we apply APT different species optimize by varying amoeba concentration, growth temperature, culture media, additives such as fungicides. optimized enriches suppresses microbial flora. Accordingly, allows identification complex water samples further pathogenic Delftia acidovorans, rare causative agent sepsis pneumonia.

Language: Английский

Epidemiology, molecular characterization, and risk factors of Acanthamoeba spp., Blastocystis spp., and Cyclospora spp. infections in snakes in China DOI
Yilei Zhang,

Zhouchun Li,

Xinyuan Wang

et al.

Veterinary Parasitology, Journal Year: 2025, Volume and Issue: 335, P. 110420 - 110420

Published: Feb. 13, 2025

Language: Английский

Citations

1
Characterization of the natural bacterial microbiota of pathogenic free-living amoebae (Acanthamoeba spp. and Naegleria fowleri) isolated from rivers and tap water in Guadeloupe DOI Creative Commons

Youri Vingataramin,

Aurélie Delumeau,

Isaure Quétel

et al.

The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 975, P. 179204 - 179204

Published: April 7, 2025

Free-living amoebae (FLA) are ubiquitous protists found in water, feeding mainly on bacteria. While most FLA harmless, Acanthamoeba spp. and Naegleria fowleri can cause keratitis and/or meningitis. host amoeba-resistant bacteria (ARB), but their natural bacterial microbiota is largely unknown. This study aimed to identify the of fowleri, castellanii, lenticulata, sp. T17, isolated from untreated (rivers) treated (tap) waters Guadeloupe. The whole water source grown with E. coli under axenic culture conditions, during successive passages, were characterized using 16S rRNA gene metabarcoding. culturable subset ARB was identified by mass spectrometry (MALDI-TOF MS) followed conventional PCR, antibiotic resistance analyzed disk diffusion method. Transmission electron microscopy used locate within amoebae. metabarcoding analyses Salmonella, Enterobacter Klebsiella genera as abundant waters. However, frequently detected (ARB) Bosea, Escherichia-Shigella, Microbacterium, Pseudomonas genera. Our findings revealed, for first time, occurrence several N. including Escherichia coli. Additionally, we Legionella A. castellanii Bordetella lenticulata. four pathogenic showed both temporary permanent associations various genera, depending number passages conditions. species distinct exhibited different antibiotics. cytoplasm trophozoites. presence Guadeloupe's drinking systems pose health risks. results highlight need regular monitoring ensure safety understanding amoebae-bacteria interactions better management. also questions immune response amoeba infection.

Language: Английский

Citations

1
Legionella pneumophila subverts the antioxidant defenses of its amoeba host Acanthamoeba castellanii. DOI Creative Commons
Alban Hay, Willy Aucher, Romain Pigeault

et al.

Current Research in Microbial Sciences, Journal Year: 2025, Volume and Issue: 8, P. 100338 - 100338

Published: Jan. 1, 2025

Legionella pneumophila, the causative agent of Legionnaires' disease, interacts in environment with free-living amoebae that serve as replicative niches for bacteria. Among these amoebae, Acanthamoeba castellanii is a natural host water networks and model commonly used to study interaction between L. pneumophila its host. However, certain crucial aspects this remain unclear. One such aspect role oxidative stress, studies focusing on reactive oxygen species (ROS) production by putting less emphasis involvement host's antioxidant defenses during infectious process. In study, we propose examine consequences infection wild-type or an isogenic ΔdotA mutant strain, which unable replicate intracellularly, A. castellanii. For purpose, looked at ROS levels, defense transcripts, metabolites linked amoeba's defenses. It known WT can block activation NADPH oxidase soon it enters macrophage suppress compared strain. addition, has been shown macrophages decreases 24 h p.i.; here confirm result suggest decrease could be partly explained differentially regulated transcripts 6 p.i.. We also explored metabolome infected not pneumophila. 617 identified, four reduced abundances may involved responses. This suggests hijack replication maintain level ROS.

Language: Английский

Citations

0
Tracing the evolution and genomic dynamics of mating-type loci inCryptococcuspathogens and closely related species DOI Creative Commons
Marco A. Coelho, Márcia David‐Palma, Seonju Marincowitz

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 16, 2025

Sexual reproduction in basidiomycete fungi is governed by MAT loci (P/R and HD), which exhibit remarkable evolutionary plasticity, characterized expansions, rearrangements, gene losses often associated with mating system transitions. The sister genera Cryptococcus Kwoniella provide a powerful framework for studying evolution owing to their diverse reproductive strategies distinct architectures, spanning bipolar tetrapolar systems either linked or unlinked loci. Building on recent large-scale comparative genomic analyses, we generated additional chromosome-level assemblies uncovering trajectories shaping organization. Contrasting the small-scale expansions acquisitions observed Kwoniella, our analyses revealed independent of P/R locus Cryptococcus, possibly driven pheromone duplications. Notably, these coincided an enrichment AT-rich codons pronounced GC-content reduction, likely recombination suppression relaxed codon usage selection. Diverse modes linkage were also identified, including three previously unrecognized transitions: one resulting pseudobipolar arrangement two leading bipolarity. All transitions involved translocations. In configuration, HD remained same chromosome but genetically unlinked, whereas additionally featured rearrangements that fused into nonrecombining region. Mating assays confirmed sexual cycle C. decagattii, demonstrating its ability undergo sporulation. Progeny analysis K. mangrovensis substantial ploidy variation aneuploidy, stemming from haploid-diploid mating, yet evidence loss heterozygosity indicates meiotic exchange occurs despite irregular segregation. Our findings underscore importance continued diversity sampling provides further convergent basidiomycetes, offering new insights genetic chromosomal changes driving

Language: Английский

Citations

0
A new understanding of Acanthamoeba castellanii: dispelling the role of bacterial pore-forming toxins in cyst formation and amoebicidal actions DOI Creative Commons
Abdelbasset Yabrag, Naeem Ullah,

Palwasha Baryalai

et al.

Cell Death Discovery, Journal Year: 2025, Volume and Issue: 11(1)

Published: Feb. 19, 2025

Language: Английский

Citations

0
Scientific Substantiation of Population Monitoring of Free-Living Protozoan Community in Natural Biotopes. Communication 1: A Review DOI
K. Yu. Kuznetsova, Rakhmanin IuA, Mikhaĭlova Ri

et al.

ЗДОРОВЬЕ НАСЕЛЕНИЯ И СРЕДА ОБИТАНИЯ - ЗНиСО / PUBLIC HEALTH AND LIFE ENVIRONMENT, Journal Year: 2025, Volume and Issue: unknown, P. 57 - 65

Published: March 1, 2025

Introduction: The relevance of the methodological development subsystem sanitary and environmental protistology in conditions high anthropogenic pressure on environment is associated with need to monitor safety cenotic changes natural ecosystems order assess their impact public health. Objective: To analyze up-to-date areas modern scientific research unicellular organisms human biota. Materials methods: article presents a literature review findings published 1990–2022 found PubMed, Google Scholar, eLibrary, CyberLeninka, Scopus, disserCat information portals platforms. topic was searched for using following keywords: protists, protistology, medical genetic morphological diversity organisms, role protozoa nature, exemplary models. initial selection consisted more than 60 publications; 40 45 initially identified articles were selected analysis. Description infrastructural components biota internal organizational inclusion criterion while that mechanisms interaction biomedical processes exclusion one.

Language: Английский

Citations

0
Moving Beyond the Silos of Opportunistic Pathogen and Disinfection Byproduct Research to Improve Drinking Water System Management DOI Creative Commons
Soojung Lee, Yue Sun,

Shi Dong Fan

et al.

Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown

Published: May 2, 2025

Drinking water opportunistic pathogens (OPs) and disinfection byproducts (DBPs) both pose risks to public health, their variable occurrence from source tap complicates efforts control them simultaneously. Management of OPs DBPs is further hindered by the historical division between microbial chemical research. This review brings together current knowledge regarding DBPs, identifies factors that influence both, highlights areas where research needed better understand health risks. First, we examine understanding how are jointly influenced physicochemical parameters, characteristics, treatment processes including disinfection, distribution system properties. Temperature, for example, can affect OP DBP occurrence, higher temperatures promote growth some OPs, such as Legionella pneumophila, but temperature's effect on species-dependent. Methods quantifying associated with (quantitative risk assessment) (chemical compared, finding numerous assumptions data gaps each method limit comparability across contaminant types. We highlight urgent need fill existing develop a more unified framework so move toward holistic assessment provides suggestions future research, highlighting ways researchers might utilize established practices in or studies our other. For analysis organic matter composition, which has advanced formation, could be utilized elucidate characteristics OPs. bridges gap disciplines, arguing collaboration two address pressing challenges facing systems today.

Language: Английский

Citations

0
Genetic Factors of Campylobacter jejuni Required for Its Interactions with Free-Living Amoeba DOI Creative Commons
Deepti Pranay Samarth,

Azam Abbasi,

Young Min Kwon

et al.

Pathogens, Journal Year: 2025, Volume and Issue: 14(6), P. 546 - 546

Published: May 31, 2025

Acanthamoeba, a free-living amoeba ubiquitous in environmental water, has been considered as the reservoir of certain bacterial pathogens, including Campylobacter jejuni, an intracellular human pathogen causing self-limiting gastroenteritis. Acanthamoeba-C. jejuni interaction mechanisms may help clarify how otherwise fastidious bacterium C. survives waters. In this study, we constructed single deletion mutants strain 81–176 for 10 selected genes (motAB, ciaB, kpsE, virB11, cheY, flaAB, cstII, docB, sodB, and cadF) previously shown to be important (invasion survival) with mammalian hosts. We used modified gentamicin protection assay quantify internalization survival these wild type two species Acanthamoeba (A. castellanii A. polyphaga). Both were significantly lower all compared both strains, except ΔcstII (p < 0.05). The results study highlight that by interact hosts are conserved its interactions This understanding useful developing effective strategies reduce transmission chickens through drinking water.

Language: Английский

Citations

0
The plumbing problem: rising antimicrobial resistance in building water systems DOI
Claire Hayward, Harriet Whiley, Nicholas J. Ashbolt

et al.

Current Opinion in Infectious Diseases, Journal Year: 2025, Volume and Issue: unknown

Published: June 5, 2025

Purpose of review This examines the interplay between biological and anthropogenic factors in development persistence antimicrobial resistance (AMR) within building plumbing systems, which is particular concern high risk setting such as healthcare facilities. The highlights role biofilms amoeba reservoirs for AMR explores how engineering design decisions, governance structures, cleaning protocols influence microbial dynamics. Recent findings Biofilms provide a protective environment that facilitates horizontal gene transfer enhances bacterial to disinfection. Amoeba-hosted bacteria can evade standard practices, further promoting persistence. Emerging technologies, digital twin modelling, offer new opportunities optimize mitigation strategies. However, more consideration needed be given or management decision may have unintended consequences, outcomes, increased biofilm growth from tap mixers low-flow fixtures, ineffective protocols, inadvertently worsen AMR. Summary Effectively managing systems requires multidisciplinary approach integrates microbiology, engineering, policy. Data driven assessments identify high-risk areas require changes but also enable targeted strategies, reducing reliance on widespread disinfection drive resistance. Future policies must consider system-wide implications prevent consequences. By addressing both drivers, we develop sustainable solutions mitigate risks beyond.

Language: Английский

Citations

0
Amoebae: beyond pathogens- exploring their benefits and future potential DOI Creative Commons

Suman Kalyan Dinda,

Shreyasee Hazra,

A. B. De

et al.

Frontiers in Cellular and Infection Microbiology, Journal Year: 2024, Volume and Issue: 14

Published: Dec. 18, 2024

Amoebae, fascinatingly diverse protists, showcase a dual nature that positions them as both friends and foes in our world. These organisms, defined by their distinctive pseudopodia, span spectrum from harmful to helpful. On the darker side, species like

Language: Английский

Citations

2