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Microorganisms Oct 2021The aims of this study were to characterize and investigate antimicrobial susceptibility and presence of integrons in 161 spp. isolated from ornamental freshwater fish...
Characterization and Antimicrobial Resistance of Environmental and Clinical Species Isolated from Fresh Water Ornamental Fish and Associated Farming Environment in Sri Lanka.
The aims of this study were to characterize and investigate antimicrobial susceptibility and presence of integrons in 161 spp. isolated from ornamental freshwater fish farming environment, apparently healthy and diseased fish. Phylogenetic analyses of the gene sequences identified as the most abundant species (75.8%) followed by (9.3%), (5%), (4.3%), (3.7%), (0.6%), (0.6%), and (0.6%). Susceptibility to thirteen antimicrobials was determined and antimicrobial resistance frequencies were: amoxicillin (92.5%), enrofloxacin (67.1%), nalidixic acid (63.4%), erythromycin (26.1%), tetracycline (23.6%), imipenem (18%), trimethoprim-sulfamethoxazole (16.8%), and gentamicin (16.8%). Multi-drug resistance (MDR) was widespread among the isolates (51.6%, 83/161) with 51.6% (63/122) isolates being MDR. In addition, 68.3% of isolates had multiple antibiotic resistance (MAR) indexes higher than 0.2, suggesting that they originated from a high-risk source of contamination where antimicrobials are often used. In all, 21.7% isolates carried class 1 integrons, with 97.1% having gene cassettes, while there were 12 isolates carrying class 2 integron gene cassettes. Our findings highlight that the aquatic environment and ornamental fish act as reservoirs of multidrug resistant spp. and underline the need for a judicious use of antimicrobials and timely surveillance of antimicrobial resistance (AMR) in aquaculture.
PubMed: 34683427
DOI: 10.3390/microorganisms9102106 -
Microbiology Spectrum Sep 2023species are emerging human enteric pathogens. This study examines the isolation of and other enteric bacterial pathogens from patients with and without inflammatory...
species are emerging human enteric pathogens. This study examines the isolation of and other enteric bacterial pathogens from patients with and without inflammatory bowel disease (IBD). This study also investigates the intestinal epithelial pathogenic mechanisms of . The isolation rates of seven enteric bacterial pathogens from 2,279 patients with IBD and 373,276 non-IBD patients were compared. An strain (AS1) isolated from intestinal biopsies of a patient with IBD was used for pathogenic mechanism investigation, and K12 was used as a bacterial control. HT-29 cells were used as a model of human intestinal epithelium. A significantly higher isolation of species was found in patients with IBD as compared to non-IBD patients ( = 0.0001, odds ratio = 2.11). upregulated 177 inflammatory genes and downregulated 52 protein-coding genes affecting chromatin assembly, multiple small nuclear RNAs, multiple nucleolar RNAs, and 55 cytoplasmic tRNAs in HT-29 cells. These downregulation effects were unique to and not observed in HT-29 cells infected with K12. induced intestinal epithelial apoptosis involving the intrinsic pathway. caused epithelial microvilli shortening and damage and epithelial production of IL-8. In conclusion, this study for the first time reports the association between IBD and enteric infection detected by bacterial cultivation. This study also reports that damages intestinal epithelial cells via multiple mechanisms, of which the downregulating cytoplasmic tRNA, small nuclear RNA, and small nucleolar RNA are novel bacterial pathogenic mechanisms. IMPORTANCE This study for the first time reports the association between inflammatory bowel disease (IBD) and enteric infection detected by bacterial pathogen cultivation, highlighting the need of clinical and public health attention. The finding that patients with IBD are more susceptible to enteric infection suggests that detection of enteric infection should be routinely performed for the diagnosis and treatment of IBD. This study also reports novel bacterial pathogenic mechanisms employed by . Through comparative transcriptomic analysis and other techniques, this study revealed the pathogenic mechanisms by which causes damage to intestinal epithelial cells. Among the various pathogenic mechanisms identified, the downregulating tRNA, small nuclear and nucleolar RNAs in human intestinal epithelial cells are novel bacterial pathogenic mechanisms.
PubMed: 37732778
DOI: 10.1128/spectrum.01088-23 -
Animals : An Open Access Journal From... Sep 2021The aim of the study was to isolate and identify species belonging to the genus and evaluate the antimicrobial resistance and virulence patterns of isolates colonizing...
The aim of the study was to isolate and identify species belonging to the genus and evaluate the antimicrobial resistance and virulence patterns of isolates colonizing European pond turtles () from natural environment of Eastern Poland. In total, 74 turtles and 15 samples of water from their natural environment were examined. More than 40 strains were isolated and identified: ( = 1), ( = 13), ( = 2), ( = 3), and ( = 23). The highest incidence of resistance was noted for ampicillin (100%) and sulfamethoxazole (62.0%), followed by erythromycin and colistin (both 40.5%). Moreover, eight strains were intermediately resistant to meropenem (19%). Most isolates were found to possess more than one virulence gene among A, , and . We showed that the population of free-living European pond turtles was highly colonized by spp. Such strains may be an infectious agent not only for the population of turtles but also for other species of animals inhabiting their natural environment. Moreover, the undesirable properties of water quality caused by the presence of drug-resistant aeromonads could have a negative impact on human health.
PubMed: 34679794
DOI: 10.3390/ani11102772 -
Biomedical and Environmental Sciences :... Sep 2022has recently been recognized as an emerging human pathogen. -associated diarrhea is a phenomenon occurring worldwide. This study was designed to determine the...
OBJECTIVE
has recently been recognized as an emerging human pathogen. -associated diarrhea is a phenomenon occurring worldwide. This study was designed to determine the prevalence, genetic diversity, antibiotic resistance, and pathogenicity of strains isolated from food products in Shanghai.
METHODS
isolates ( = 79) collected from food samples were analyzed using concatenated - sequencing. The antibiotic resistance of these isolates was determined using antimicrobial susceptibility testing. Pathogenicity was assessed using β-hemolytic, extracellular protease, virulence gene detection, liquid toxicity (LT), and cytotoxicity assays.
RESULTS
Eight different species were identified among the 79 isolates. The most prevalent species were [62 (78.5%)], [6 (7.6%)], [3 (3.8%)], and [3 (3.8%)]. The isolates were divided into 73 sequence types (STs), of which 65 were novel. The isolates were hemolytic (45.6%) and protease-positive (81.0%). The most prevalent virulence genes were (73.4%), (69.6%), (36.7%), and (30.4%). The results of LT and cytotoxicity assays revealed that and were more virulent than , , and . Antibiotic resistance genes [ , , , , , mcr , and ] were detected in the isolates. The multidrug-resistance rate of the isolates was 11.4%, and 93.7% of the isolates were resistant to cefazolin.
CONCLUSION
The taxonomy, antibiotic resistance, and pathogenicity of different species varied. The isolates and were highly pathogenic, indicating that food-derived isolates are potential risks for public health and food safety. The monitoring of food quality and safety will result in better prevention and treatment strategies to control diarrhea illnesses in China.
Topics: Aeromonas; Animals; Anti-Bacterial Agents; Caenorhabditis elegans; Cefazolin; China; Diarrhea; Drug Resistance, Multiple, Bacterial; Genetic Variation; Humans; Peptide Hydrolases; Virulence
PubMed: 36189999
DOI: 10.3967/bes2022.108 -
Frontiers in Microbiology 2022Lake Cajititlán is a subtropical and endorheic lake, which is heavily impacted by nutrient pollution. Agricultural runoff and poorly treated wastewater have entered...
Lake Cajititlán is a subtropical and endorheic lake, which is heavily impacted by nutrient pollution. Agricultural runoff and poorly treated wastewater have entered this reservoir at alarming rates during past rainy seasons, causing the cultural eutrophication of this body of water and resulting in several massive fish kill events. In this study, shotgun metagenomic sequencing was used to examine the taxonomic and functional structure of microbial communities in Lake Cajititlán during the rainy season. Several water quality features and their interactions with microbial communities were also assessed to identify the major factors affecting the water quality and biota, specifically fish species. According to current water quality regulations, most of the physicochemical variables analyzed (dissolved oxygen, pH, Secchi disk, NH , NO , blue-green algae, total phosphorus, and chlorophyll-) were outside of the permissible limits. and were the most abundant phytoplankton species, and the dominant bacterial genera were , , and , with , , and representing the most abundant bacterial species. All of these microorganisms have been reported to be potentially harmful to fish, and the latter three (, , ) also contain genes associated with pathogenicity in fish mortality (, S, , , , , , ). Genetic evidence from the microbial communities analyzed herein reveals that anthropogenic sources of nutrients in the lake altered genes involved in nitrogen, phosphorus, sulfur, and carbon metabolism, mainly at the beginning of the rainy season. These findings suggest that abiotic factors influence the structure of the microbial communities, along with the major biogeochemical cycles of Lake Cajititlán, resulting in temporal variations and an excess of microorganisms that can thrive in high-nutrient and low-oxygen environments. After reviewing the literature, this appears to be the first study that focuses on characterizing the water quality of a subtropical hypereutrophic lake through associations between physicochemical variables and shotgun metagenomic data. In addition, there are few studies that have coupled the metabolism of aquatic ecosystems with nutrient cycles.
PubMed: 36532453
DOI: 10.3389/fmicb.2022.1037626 -
Frontiers in Immunology 2022are autochthonous bacteria of aquatic environments that are considered to be emerging pathogens to humans, producing diarrhea, bacteremia, and wound infections. Genetic...
are autochthonous bacteria of aquatic environments that are considered to be emerging pathogens to humans, producing diarrhea, bacteremia, and wound infections. Genetic identification shows that 95.4% of the strains associated with clinical cases correspond to the species (37.26%), (23.49%), (21.54%), and (13.07%). However, few studies have investigated the human immune response against some spp. such as , , and . The present study aimed to increase the knowledge about the innate human immune response against six species, using, for the first time, an infection model with the monocytic human cell line THP-1, and to evaluate the intracellular survival, the cell damage, and the expression of 11 immune-related genes (, , , , , , , , , , and ). Transcriptional analysis showed an upregulated expression of a variety of the monocytic immune-related genes, with a variable response depending upon the species. The species that produced the highest cell damage, independently of the strain origin, coincidentally induced a higher expression of immune-related genes and corresponded to the more prevalent clinical species , , and . Additionally, monocytic cells showed an overexpression of the apoptotic and pyroptotic genes involved in cell death after , , and infection. However, the apoptosis route seemed to be the only way of producing cell damage and death in the case of the species and , while apparently only used the pyroptosis route.
Topics: Aeromonas; Aeromonas hydrophila; Cell Line; Gram-Negative Bacterial Infections; Humans; Immunity
PubMed: 35874671
DOI: 10.3389/fimmu.2022.875689 -
Journal of Medical Case Reports Jan 2023Skin and soft tissue infections are common because of exposure to aquatic environment, while severe infections caused by Aeromonas veronii are rare.
INTRODUCTION
Skin and soft tissue infections are common because of exposure to aquatic environment, while severe infections caused by Aeromonas veronii are rare.
CASE PRESENTATION
We report a case of severe skin and soft tissue infection of the left upper limb caused by Aeromonas veronii. A 50-year-old Chinese woman, who had a history of cardiac disease and type 2 diabetes mellitus, accidentally injured her left thumb while cutting a fish. Early antibiotic therapy and surgical debridement was performed before the result of bacterial culture came back. Whole-genome sequencing was further performed to confirm the pathogen and reveal the drug resistance and virulence genes. The wound was gradually repaired after 1 month of treatment, and the left hand recovered well in appearance and function after 3 months of rehabilitation.
CONCLUSION
Early diagnosis, surgical intervention, and administration of appropriate antibiotics are crucial for patients who are suspected of having skin and soft tissue infection, or septicemia caused by Aeromonas veronii.
Topics: Animals; Female; Humans; Aeromonas veronii; Soft Tissue Infections; Aeromonas; Diabetes Mellitus, Type 2; Gram-Negative Bacterial Infections; Anti-Bacterial Agents; Upper Extremity
PubMed: 36710352
DOI: 10.1186/s13256-023-03770-y -
Fish & Shellfish Immunology Jul 2022The potential of rice protein concentrate (RPC) to substitute fishmeal (FM) protein in the diet of Oreochromis niloticus was assessed in a five-month-long feeding trial....
Rice protein concentrate as a fish meal substitute in Oreochromis niloticus: Effects on immune response, intestinal cytokines, Aeromonas veronii resistance, and gut microbiota composition.
The potential of rice protein concentrate (RPC) to substitute fishmeal (FM) protein in the diet of Oreochromis niloticus was assessed in a five-month-long feeding trial. Fishmeal protein was replaced by RPC at rates of 0% (control), 25%, 50%, and 75% (RPC0, RPC25, RPC50, and RPC75, respectively). RPC25 had no significant effect on antioxidant capacity (total antioxidant capacity; superoxide dismutase, catalase, and glutathione peroxidase activities) and immune indices (lysozyme, nitric oxide, antiprotease, and bactericidal activities) after one, two, and five months of feeding, while the values for these parameters were significantly lower in the RPC75 group compared to those in the RPC0 group. The RPC25 group showed higher mRNA levels of the intestinal cytokines IL-1β, IL-10β, TGF-β, and TNF-α than the control group. In fish affected by Aeromonas veronii, the highest significant cumulative mortality was recorded in the RPC75 group, followed by the RPC50, RPC25, and control groups. Gut microbiome analyses showed a reduction in microbial diversity in response to the addition of RPC, regardless of the RPC content, and the composition of the community of the RPC samples differed from that of the control. RPC-enriched diets resulted in higher relative abundances of Bacteroidetes and Fusobacteria in the gut compared to that in the gut of the control fish. In summary, RPC can be used to replace up to 25% of the FM protein in the diet of O. niloticus, while improving the antioxidant capacity, immunocompetence, and disease resistance of the fish.
Topics: Aeromonas veronii; Animal Feed; Animals; Antioxidants; Cichlids; Cytokines; Diet; Disease Resistance; Fish Diseases; Gastrointestinal Microbiome; Gram-Negative Bacterial Infections; Oryza
PubMed: 35654384
DOI: 10.1016/j.fsi.2022.05.048 -
PloS One Feb 2011Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group,...
Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group, that inhabit a wide range of host animals as a symbiont or pathogen. In this study, the ability of various strains to colonize the medicinal leech as a model for beneficial symbiosis and to kill wax worm larvae as a model for virulence was determined. Isolates cultured from the leech out-competed other strains in the leech model, while most strains were virulent in the wax worms. Three housekeeping genes, recA, dnaJ and gyrB, the gene encoding chitinase, chiA, and four loci associated with the type three secretion system, ascV, ascFG, aexT, and aexU were sequenced. The phylogenetic reconstruction failed to produce one consensus tree that was compatible with most of the individual genes. The Approximately Unbiased test and the Genetic Algorithm for Recombination Detection both provided further support for differing evolutionary histories among this group of genes. Two contrasting tests detected recombination within aexU, ascFG, ascV, dnaJ, and gyrB but not in aexT or chiA. Quartet decomposition analysis indicated a complex recent evolutionary history for these strains with a high frequency of horizontal gene transfer between several but not among all strains. In this study we demonstrate that at least for some strains, horizontal gene transfer occurs at a sufficient frequency to blur the signal from vertically inherited genes, despite strains being adapted to distinct niches. Simply increasing the number of genes included in the analysis is unlikely to overcome this challenge in organisms that occupy multiple niches and can exchange DNA between strains specialized to different niches. Instead, the detection of genes critical in the adaptation to specific niches may help to reveal the physiological specialization of these strains.
Topics: Aeromonas; Animals; Base Sequence; DNA, Bacterial; Evolution, Molecular; Genotype; Gram-Negative Bacterial Infections; Host-Pathogen Interactions; Molecular Sequence Data; Phenotype; Phylogeny; Sequence Analysis, DNA; Symbiosis
PubMed: 21359176
DOI: 10.1371/journal.pone.0016751 -
Applied and Environmental Microbiology Apr 2021By characterizing the trajectories of antibiotic resistance gene transfer in bacterial communities such as the gut microbiome, we will better understand the factors that...
By characterizing the trajectories of antibiotic resistance gene transfer in bacterial communities such as the gut microbiome, we will better understand the factors that influence this spread of resistance. Our aim was to investigate the host network of a multidrug resistance broad-host-range plasmid in the culturable gut microbiome of zebrafish. This was done through and conjugation experiments with as the donor of the plasmid pB10:: When this donor was mixed with the extracted gut microbiome, only transconjugants of were detected. In separate matings between the same donor and four prominent isolates from the gut microbiome, the plasmid transferred to two of these four isolates, and , but not to and When these and transconjugants were the donors in matings with the same four isolates, the plasmid now also transferred from to was unable to donate the plasmid, and was unable to acquire it. Finally, when the donor was added to zebrafish through their food, plasmid transfer was observed in the gut, but only to , a rare member of the gut microbiome. This work shows that the success of plasmid-mediated antibiotic resistance spread in a gut microbiome depends on the donor-recipient species combinations and therefore their spatial arrangement. It also suggests that rare gut microbiome members should not be ignored as potential reservoirs of multidrug resistance plasmids from food. To understand how antibiotic resistance plasmids end up in human pathogens, it is crucial to learn how, where, and when they are transferred and maintained in members of bacterial communities such as the gut microbiome. To gain insight into the network of plasmid-mediated antibiotic resistance sharing in the gut microbiome, we investigated the transferability and maintenance of a multidrug resistance plasmid among the culturable bacteria of the zebrafish gut. We show that the success of plasmid-mediated antibiotic resistance spread in a gut microbiome can depend on which species are involved, as some are important nodes in the plasmid-host network and others are dead ends. Our findings also suggest that rare gut microbiome members should not be ignored as potential reservoirs of multidrug resistance plasmids from food.
Topics: Animals; Bacteria; Drug Resistance, Multiple, Bacterial; Female; Gastrointestinal Microbiome; Male; Plasmids; Zebrafish
PubMed: 33637574
DOI: 10.1128/AEM.02735-20