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Frontiers in Cellular and Infection... 2023is an important pathogen that mainly harms aquatic animals and exhibits resistance to a variety of antibiotics. This study investigated the effect of...
BACKGROUND
is an important pathogen that mainly harms aquatic animals and exhibits resistance to a variety of antibiotics. This study investigated the effect of epigallocatechin-3-gallate (EGCG) on the virulence factors of and its impact on adhesion, invasion, and cytotoxicity in Caco-2 cells. The potential mechanism of antibacterial activity of EGCG was investigated by transcriptomic analysis.
RESULTS
EGCG not only inhibited the production of biofilm, hemolytic activity, motility, and protease activity of , but also reduced its adhesion, invasion, and cytotoxicity in Caco-2 cells. Transcriptomic analysis indicated that the antimicrobial activity of EGCG may be achieved by weakening the chemotaxis and stress response of the bacteria, as well as inhibiting the TonB system. Animal studies demonstrated that EGCG can significantly improve the survival rate and organs damage of zebrafish infected with .
CONCLUSION
EGCG would be a potential alternative drug for the prevention and treatment of infections by anti-virulence mechanism.
Topics: Animals; Humans; Aeromonas hydrophila; Zebrafish; Caco-2 Cells; Transcriptome; Anti-Bacterial Agents; Gram-Negative Bacterial Infections
PubMed: 37868352
DOI: 10.3389/fcimb.2023.1271448 -
Microbial Pathogenesis Dec 2023Zebrafish (Danio rerio) is an excellent model to study bacterial infections in fish and their treatment. We used zebrafish as a model of infection for Aeromonas...
Zebrafish (Danio rerio) is an excellent model to study bacterial infections in fish and their treatment. We used zebrafish as a model of infection for Aeromonas salmonicida subsp. salmonicida (hereinafter A. salmonicida), the causative agent of fish furunculosis. The infection process of A. salmonicida was studied by immersion of zebrafish larvae in 2 different doses of the bacteria and the fish mortality was monitored for three days. The bacterium caused a high mortality (65 %) in zebrafish larvae only when they were exposed to a high bacterial concentration (10 bacterial cells/mL). To evaluate the use of fluorescence microscopy to follow A. salmonicida infection in vivo, two different fluorescent strains generated by labeling an A. salmonicida strain with either, the green fluorescent protein (GFP), or with a previously reported siderophore amonabactin-sulforhodamine B conjugate (AMB-SRB), were used. The distribution of both labeled bacterial strains in the larvae tissues was evaluated by conventional and confocal fluorescence microscopy. The fluorescent signal showed a greater intensity with the GFP-labeled bacteria, so it could be observed using conventional fluorescence microscopy. Since the AMB-SRB labeled bacteria showed a weaker signal, the larvae were imaged using a laser scanning confocal microscope after 48 h of exposure to the bacteria. Both fluorescent signals were mainly observed in the larvae digestive tract, suggesting that this is the main colonization route of zebrafish for waterborne A. salmonicida. This is the first report of the use of a siderophore-fluorophore conjugate to study a bacterial infection in fish. The use of a siderophore-fluorophore conjugate has the advantage that it is a specific marker and that does not require genetic manipulation of the bacteria.
Topics: Animals; Siderophores; Zebrafish; Fluorescent Dyes; Green Fluorescent Proteins; Aeromonas salmonicida; Fish Diseases
PubMed: 37858632
DOI: 10.1016/j.micpath.2023.106394 -
Microbiology Spectrum Dec 2023In this work, we demonstrate the epidemiologic relevance of the genus as the cause of infective diarrhea in North East Italy, both in children and adult subjects, with...
In this work, we demonstrate the epidemiologic relevance of the genus as the cause of infective diarrhea in North East Italy, both in children and adult subjects, with the significative presence of highly pathogenic strains. strains possess a heterogeneous armamentarium of pathogenicity factors that allows the microbe to affect a wide range of human intestinal epithelial cell processes that justify the ability to induce diarrhea through different mechanisms and cause diseases of variable severity, as observed for other gastrointestinal pathogens. However, it remains to be determined whether specific genotype(s) are associated with clinical pictures of different severity to implement the diagnostic and therapeutic approaches for this relevant enteric pathogen.
Topics: Child; Adult; Humans; Virulence; Aeromonas; Prevalence; Diarrhea; Italy
PubMed: 37855641
DOI: 10.1128/spectrum.00807-23 -
Virulence Dec 2023The emergence of antibiotic-resistant strains in clinical settings has presented an escalating burden on human and public health. The dissemination of antibiotic...
The emergence of antibiotic-resistant strains in clinical settings has presented an escalating burden on human and public health. The dissemination of antibiotic resistance in is predominantly facilitated by chromosome-borne accessory genetic elements, although the existing literature on this subject remains limited. Hence, the primary objective of this study is to comprehensively investigate the genomic characteristics of chromosome-borne accessory genetic elements in . Moreover, the study aims to uncover novel genetic environments associated with antibiotic resistance on these elements. were screened from nonduplicated strains collected from two tertiary hospitals in China. Complete sequencing and population genetics analysis were performed. BLAST analysis was employed to identify related elements. All newly identified elements were subjected to detailed sequence annotation, dissection, and comparison. We identified and newly designated 19 chromosomal elements, including 18 integrative and mobilizable elements (IMEs) that could be classified into four categories: Tn-related, Tn-related, Tn-related, and Tn-related IMEs. Each class exhibited a distinct pattern in the types of resistance genes carried by the IMEs. Several novel antibiotic resistance genetic environments were uncovered in these elements. Notably, we report the first identification of the gene and gene in clinical genome, the first presence of a (E)-(E) resistance gene environment within the backbone region in IMEs, and a new resistance gene environment. The implications of these findings are substantial, as they provide new insights into the evolution, structure, and dissemination of chromosomal-borne accessory elements.
Topics: Humans; Aeromonas; Drug Resistance, Microbial; Anti-Bacterial Agents; Chromosomes; China
PubMed: 37848422
DOI: 10.1080/21505594.2023.2271688 -
BMC Infectious Diseases Oct 2023Aeromonas hydrophila can cause a wide range of diseases and is mainly found in patients with underlying diseases. Globally the data on Aeromonas infections is limited,...
BACKGROUND
Aeromonas hydrophila can cause a wide range of diseases and is mainly found in patients with underlying diseases. Globally the data on Aeromonas infections is limited, and no studies have been published about the situation in Saudi Arabia. The aim of this study was to investigate the risk factors, clinical presentation, treatment, and outcomes of Aeromonas infections in Saudi Arabia.
METHODS
A retrospective study was performed at a tertiary university hospital with 1000 beds in Jeddah, Saudi Arabia. All patients 14 years and older with Aeromonas-positive cultures between January 1, 2015, and December 31, 2022 were included. Patient information was extracted from the electronic health records, including patient demographics, comorbidities, presenting symptoms, source of infection, human immunodeficiency virus status, culture results and antimicrobial susceptibility, use of immunosuppressive medication, and 30-day mortality.
RESULTS
In total 24 patients were identified with Aeromonas hydrophila-positive cultures, 22 of which were males (91.7%), and most (75%) had hospital-acquired infections. The 30-day mortality was 20.8%. All Aeromonas cultures were susceptible to gentamicin, cefepime, and ciprofloxacin, while the majority were resistant to ceftazidime (83.3%) and meropenem (62.5%). The most common disease presentation was skin and soft tissue infection (33.3%), the most common clinical sign was fever (58.3%), and the most common symptom was abdominal pain (37.5%). Comorbidities were very common (median 3, range 1-7). Pitt bacteremia score (p < 0.001), Charlson weighted comorbidity index (p < 0.02), international normalized ratio (p < 0.005), and the number of comorbidity factors (p < 0.05) were all associated with 30-day mortality due to Aeromonas infection. The number of comorbidities had the best predictive value (83.3%) of 30-day mortality (p < 0.05, Odds ratio 3.253, 95% confidence interval: 1.088-9.729).
CONCLUSIONS
Aeromonas hydrophila is an important pathogen to consider in nosocomial infections. The number of comorbidities had the best predictive value of 30-day mortality. The susceptibility pattern of this organism indicates that, in Saudi Arabia, when an Aeromonas infection is suspected, treatment with quinolone along with other broad-spectrum antibiotics should be started until the culture and susceptibility results are known.
Topics: Male; Humans; Female; Aeromonas hydrophila; Retrospective Studies; Tertiary Care Centers; Saudi Arabia; Anti-Bacterial Agents; Aeromonas
PubMed: 37814215
DOI: 10.1186/s12879-023-08660-8 -
Microbiology Spectrum Dec 2023The emergence and spread of carbapenemase-producing organisms (CPOs) represent a global health threat because they are associated with limited treatment options and poor...
Municipal wastewater monitoring revealed the predominance of genes with diverse variants among carbapenemase-producing organisms: high occurrence and persistence of harboring the new variant .
The emergence and spread of carbapenemase-producing organisms (CPOs) represent a global health threat because they are associated with limited treatment options and poor clinical outcomes. Wastewater is considered a hotspot for the evolution and dissemination of antimicrobial resistance. Thus, analyses of municipal wastewater are critical for understanding the circulation of these CPOs and carbapenemase genes in local communities, which remains scarcely known in Japan. This study resulted in several key observations: (i) the vast majority of genes, including six new variants, and less frequent genes were carbapenemase genes encountered exclusively in wastewater influent; (ii) the most dominant CPO species were spp., in which a remarkable diversity of new sequence types was observed; and (iii) CPOs were detected from combined sewer wastewater, but not from separate sewer wastewater, suggesting that the load of CPOs from unrecognized environmental sources could greatly contribute to their detection in influent wastewater.
Topics: Aeromonas caviae; Wastewater; beta-Lactamases; Bacterial Proteins; Microbial Sensitivity Tests; Anti-Bacterial Agents
PubMed: 37811969
DOI: 10.1128/spectrum.02188-23 -
Environmental Research Dec 2023The overuse of antibiotics in aquaculture drives the emergence of multi-drug-resistant bacteria, and antibiotic-resistant genes (ARGs) can be disseminated to other...
The overuse of antibiotics in aquaculture drives the emergence of multi-drug-resistant bacteria, and antibiotic-resistant genes (ARGs) can be disseminated to other bacteria through vertical- and horizontal gene transfer (VGT and HGT) under selective pressure. Profiling the antibiotic resistome and understanding the global distribution of ARGs constitutes the first step in developing a control strategy. Hence, this study utilized extensive genomic data from hundreds of Aeromonas strains in aquaculture to profile resistome patterns and explores their association with isolation year, country, and species characteristics. Overall, ∼400 Aeromonas genomes were used to predict the ARGs from A. salmonicida, A. hydrophila, A. veronii, A. media, and A. sobria. ARGs such as sul1, tet(A), and tet(D), which display a similar proportion of positive strains among species, were subjected to phylodynamic and phylogeographic analyses. More than a hundred ARGs were identified, some of which exhibited either species-specific or non-species-specific patterns. A. salmonicida and A. media were found to have a higher proportion of species-specific ARGs than other strains, which might lead to more distinct patterns of ARG acquisition. Overall, ∼25% of strains have either sul1, tet(A), or tet(D) gene(s), but no significant difference was observed in the proportion of positive strains by species. Phylogeographic analysis revealed that the abundant numbers of sul1, tet(A), and/or tet(D) introduced in a few East Asian and North American countries could spread to both adjacent and faraway countries. In recent years, the proportions of these ARGs have dramatically increased, particularly in strains sourced from aquatic environments, suggesting control is required of the overuse of antibiotics in aquaculture. The findings of this research offer significant insights into the global dissemination of ARGs.
Topics: Aeromonas; Anti-Bacterial Agents; Drug Resistance, Multiple, Bacterial; Aquaculture; North America; Genes, Bacterial
PubMed: 37805184
DOI: 10.1016/j.envres.2023.117273 -
Journal of Agricultural and Food... Nov 2023Lactic acid bacteria (LAB) were screened from (red sea bass), and their antimicrobial activities were evaluated against two species isolated from the , namely, (AV)...
Lactic acid bacteria (LAB) were screened from (red sea bass), and their antimicrobial activities were evaluated against two species isolated from the , namely, (AV) and (AJ). Three LAB isolates, MU8 (EF_8), MU2 (EFL_2), and MU9 (EFL_9), were found to inhibit both AV and AJ; however, their cell-free supernatant (CFS) did not do so. Interestingly, bacteriocin-like substances (BLS) induced by cocultures of EF_8 with AV exhibited the highest antimicrobial activity against both sp. The size of BLS was less than 1.0 kDa; the purified BLS were susceptible to proteinase K digestion, indicating that they are peptides. BLS contained 13 identified peptides derived from as determined by liquid chromatography-tandem mass spectrometry. Cocultures of Gram-positive-producing and -inducing LAB strains have been used to increase bacteriocin yields. To our knowledge, this is the first report describing inducible BLS produced by cocultures of Gram-positive-producing and Gram-negative-inducing strains.
Topics: Enterococcus faecium; Bacteriocins; Aeromonas veronii; Coculture Techniques; Aeromonas; Peptides; Anti-Infective Agents; Anti-Bacterial Agents
PubMed: 37779478
DOI: 10.1021/acs.jafc.3c04019 -
American Journal of Infection Control Mar 2024Aquatic opportunistic pathogen Aeromonas hydrophila, known to persist in low-nutrient chlorinated waters, can cause life-threatening infections. Two intensive care units...
BACKGROUND
Aquatic opportunistic pathogen Aeromonas hydrophila, known to persist in low-nutrient chlorinated waters, can cause life-threatening infections. Two intensive care units experienced a cluster of Aeromonas infections following outdoor temperature spikes coinciding with recurrent plumbing issues, with fatalities due to severe underlying comorbidities co-occurring with extensively-drug resistant (XDR) Aeromonas.
METHODS
We investigated this cluster using whole genome sequencing to assess genetic relatedness of isolates and identify antimicrobial resistance determinants. Three A. hydrophila were isolated from patients staying in or adjacent to rooms with plumbing issues during or immediately after periods of elevated outdoor temperatures. Sinks and faucets were swabbed for culture.
RESULTS
All A. hydrophila clinical isolates exhibited carbapenem resistance but were not genetically related. Diverse resistance determinants corresponding to extensively-drug resistant were found, including co-occurring KPC-3 and VIM-2, OXA-232, and chromosomal CphA-like carbapenemase genes, contributing to major treatment challenges. All 3 patients were treated with multiple antibiotic regimens to overcome various carbapenemase classes and expired due to underlying comorbidities. Environmental culture yielded no Aeromonas.
CONCLUSIONS
While the investigation revealed no singular source of contamination, it supports a possible link between plumbing issues, elevated outdoor temperatures and incidence of nosocomial Aeromonas infections. The diversity of carbapenemase genes detected in these wastewater-derived Aeromonas warrants heightened infection prevention precautions during periods of plumbing problems especially with heat waves.
Topics: Humans; Aeromonas hydrophila; Sanitary Engineering; Cross Infection; Hot Temperature; beta-Lactamases; Aeromonas; Anti-Bacterial Agents; Microbial Sensitivity Tests; Bacterial Proteins
PubMed: 37778710
DOI: 10.1016/j.ajic.2023.09.013 -
PloS One 2023Water quality parameters influence the abundance of pathogenic bacteria. The genera Aeromonas, Arcobacter, Klebsiella, and Mycobacterium are among the representative...
Quantitative detection and reduction of potentially pathogenic bacterial groups of Aeromonas, Arcobacter, Klebsiella pneumoniae species complex, and Mycobacterium in wastewater treatment facilities.
Water quality parameters influence the abundance of pathogenic bacteria. The genera Aeromonas, Arcobacter, Klebsiella, and Mycobacterium are among the representative pathogenic bacteria identified in wastewater. However, information on the correlations between water quality and the abundance of these bacteria, as well as their reduction rate in existing wastewater treatment facilities (WTFs), is lacking. Hence, this study aimed to determine the abundance and reduction rates of these bacterial groups in WTFs. Sixty-eight samples (34 influent and 34 non-disinfected, treated, effluent samples) were collected from nine WTFs in Japan and Thailand. 16S rRNA gene amplicon sequencing analysis revealed the presence of Aeromonas, Arcobacter, and Mycobacterium in all influent wastewater and treated effluent samples. Quantitative real-time polymerase chain reaction (qPCR) was used to quantify the abundance of Aeromonas, Arcobacter, Klebsiella pneumoniae species complex (KpSC), and Mycobacterium. The geometric mean abundances of Aeromonas, Arcobacter, KpSC, and Mycobacterium in the influent wastewater were 1.2 × 104-2.4 × 105, 1.0 × 105-4.5 × 106, 3.6 × 102-4.3 × 104, and 6.9 × 103-5.5 × 104 cells mL-1, respectively, and their average log reduction values were 0.77-2.57, 1.00-3.06, 1.35-3.11, and -0.67-1.57, respectively. Spearman's rank correlation coefficients indicated significant positive or negative correlations between the abundances of the potentially pathogenic bacterial groups and Escherichia coli as well as water quality parameters, namely, chemical/biochemical oxygen demand, total nitrogen, nitrate-nitrogen, nitrite-nitrogen, ammonium-nitrogen, suspended solids, volatile suspended solids, and oxidation-reduction potential. This study provides valuable information on the development and appropriate management of WTFs to produce safe, hygienic water.
Topics: Wastewater; Arcobacter; Klebsiella pneumoniae; Klebsiella; Aeromonas; RNA, Ribosomal, 16S; Escherichia coli; Water Purification; Mycobacterium
PubMed: 37768925
DOI: 10.1371/journal.pone.0291742