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Microorganisms Jul 2021species are emerging human enteric pathogens. However, systematic analysis of species infection in human gastroenteritis in comparison with other enteric bacterial...
species are emerging human enteric pathogens. However, systematic analysis of species infection in human gastroenteritis in comparison with other enteric bacterial pathogens in the Australian population is lacking. Here we analysed the isolation of species and other bacterial pathogens in five consecutive years (2015-2019) from 375,842 stool samples of patients with gastroenteritis in a large Australian diagnostic laboratory and identified a subset (48 isolates) of isolates to species level, using multilocus phylogenetic analysis. species were the third most common bacterial pathogens, following and species. infection rate was significantly correlated with increasing age ( < 0.001). species were more often isolated in warm seasons and in males than females ( < 0.001). Five species were identified. Most of the infections were from three species, namely (52%), (27%) and (12.5%). The majority of patients with species infection did not have a documented overseas travel history. The findings from this study support the importance of species in human gastroenteritis and suggest that the sources of infection in Australian patients should be further investigated.
PubMed: 34361876
DOI: 10.3390/microorganisms9071440 -
Veterinary World Sep 2023The high diversity of spp. results in various pathogenicity levels. This group of bacteria causes a serious disease named motile septicemia (MAS) in catfish ( spp.)....
BACKGROUND AND AIM
The high diversity of spp. results in various pathogenicity levels. This group of bacteria causes a serious disease named motile septicemia (MAS) in catfish ( spp.). This study aimed to characterize the species and virulence gene diversity of spp. isolated from diseased catfish.
MATERIALS AND METHODS
Nine spp. were isolated from infected catfish cultivated in Java, Indonesia, and they were identified at the phenotypic and molecular levels (16S rDNA). The virulence genes assessed included , , , , , and .
RESULTS
Phylogenetic analysis identified nine isolates of spp.: (11.11%), (11.11%), bv. (44.44%), and (33.33%). Virulence genes, such as , , , , , and , were detected in all isolates at frequencies of approximately 100%, 66.67%, 88.89%, 100%, 55.56%, and 66.67%, respectively. This study is the first report on recovered from an Indonesian catfish culture. Furthermore, our study revealed the presence of . bv , a biovar that has not been reported before in Indonesia.
CONCLUSION
This finding confirms that MAS was caused by multiple species of , notably and . bv , within Indonesian fish culture. The presence of these species with multiple virulence genes poses a significant threat to the freshwater aquaculture industry.
PubMed: 37859968
DOI: 10.14202/vetworld.2023.1974-1984 -
PloS One 2019Aeromonas veronii is a gram-negative species abundant in aquatic environments that causes disease in humans as well as terrestrial and aquatic animals. In the current...
Aeromonas veronii is a gram-negative species abundant in aquatic environments that causes disease in humans as well as terrestrial and aquatic animals. In the current study, 41 publicly available A. veronii genomes were compared to investigate distribution of putative virulence genes, global dissemination of pathotypes, and potential mechanisms of virulence. The complete genome of A. veronii strain ML09-123 from an outbreak of motile aeromonas septicemia in farm-raised catfish in the southeastern United States was included. Dissemination of A. veronii strain types was discovered in dispersed geographical locations. Isolate ML09-123 is highly similar to Chinese isolate TH0426, suggesting the two strains have a common origin and may represent a pathotype impacting aquaculture in both countries. Virulence of strain ML09-123 in catfish in a dose-dependent manner was confirmed experimentally. Subsystem category disposition showed the majority of genomes exhibit similar distribution of genomic elements. The type I secretion system (T1SS), type II secretion system (T2SS), type 4 pilus (T4P), and flagellum core elements are conserved in all A. veronii genomes, whereas the type III secretion system (T3SS), type V secretion system (T5SS), type VI secretion system (T6SS), and tight adherence (TAD) system demonstrate variable dispersal. Distribution of mobile elements is dependent on host and geographic origin, suggesting this species has undergone considerable genetic exchange. The data presented here lends insight into the genomic variation of A. veronii and identifies a pathotype impacting aquaculture globally.
Topics: Aeromonas veronii; Animals; Aquaculture; Genomics; Gram-Negative Bacterial Infections; Humans; Virulence Factors; Water Microbiology
PubMed: 31465454
DOI: 10.1371/journal.pone.0221018 -
Animals : An Open Access Journal From... May 2023Nanotechnology can enhance nutrient delivery and bioavailability; hence, it has recently been considered the most practical alternative technology for nutritional...
Nanotechnology can enhance nutrient delivery and bioavailability; hence, it has recently been considered the most practical alternative technology for nutritional supplements and disease control in fish farming. The present study was designed to evaluate the effects of mangosteen peel extract loaded in nanoemulsion (MSNE) on the inhibition of (in vitro) and in vivo growth performance, serum biochemical parameters, the immune response, and the disease resistance of Nile tilapia () against challenge. The particle size, polydispersity index, and particle surface charge of MSNE were 151.9 ± 1.4 nm, >0.3, and -30 mV, respectively. Furthermore, MSNE, mangosteen peel extract (MPE), and nanoemulsion (NE) improved the antimicrobial activity against . Fish fed MSNE, MPE, and NE-supplemented diets had a significantly lower ( < 0.05) feed conversion ratio (FCR) and higher specific growth rate (SGR) than fish fed the control diet. Furthermore, the MSNE had significantly higher serum glucose and protein levels than the control group in Nile tilapia. Total immunoglobulin, serum lysozyme, alternative complement activity, and survival of Nile tilapia fed with MSNE were significantly higher ( < 0.05) than the control diet. Therefore, MSNE has the potential to be employed as a supplement in sustainable Nile tilapia farming.
PubMed: 37889734
DOI: 10.3390/ani13111798 -
Frontiers in Microbiology 2023is a Gram-negative bacterium ubiquitously found in aquatic environments. It is a foodborne pathogen that causes diarrhea in humans and hemorrhagic septicemia in fish....
The mobile gene cassette carrying tetracycline resistance genes in strain Ah5S-24 isolated from catfish pond sediments shows similarity with a cassette found in other environmental and foodborne bacteria.
is a Gram-negative bacterium ubiquitously found in aquatic environments. It is a foodborne pathogen that causes diarrhea in humans and hemorrhagic septicemia in fish. In the present study, we used whole-genome sequencing (WGS) to evaluate the presence of antimicrobial resistance (AMR) and virulence genes found in Ah5S-24 isolated from catfish pond sediments in South-East, United States. We found , , , , , and resistance genes encoded in the chromosome of Ah5S-24. We also found the tetracycline and genes placed next to the ISIS transposase, integrase, and hypothetical proteins that formed as a genetic structure or transposon designated as ISIS. BLAST analysis showed that a similar mobile gene cassette (MGC) existed in chromosomes of other bacteria species such as isolated from retail fish at markets, from human stool and from a sewage bioreactor. In addition, the ISIS cassette was also found in the plasmid of isolated from shrimp. As for virulence genes, we found the tap type IV pili ( and ), polar flagellae ( and ), lateral flagellae ( and ), and fimbriae ( and ) genes responsible for motility and adherence. We also found the hemolysin genes (, and ), toxin, biofilm formation, and quorum sensing (, and ) genes. However, there were no MGCs encoding virulence genes found in AhS5-24. Thus, our findings show that MGCs could play a vital role in the spread of AMR genes between chromosomes and plasmids among bacteria in aquatic environments. Overall, our findings are suggesting that MGCs encoding AMR genes could play a vital role in the spread of resistance acquired from high usage of antimicrobials in aquaculture to animals and humans.
PubMed: 37007502
DOI: 10.3389/fmicb.2023.1112941 -
Pharmaceuticals (Basel, Switzerland) Jun 2021Mycobacteriosis affects wild fish and aquaculture worldwide, and alternatives to antibiotics are needed for an effective and environmentally sound control of infectious...
Mycobacteriosis affects wild fish and aquaculture worldwide, and alternatives to antibiotics are needed for an effective and environmentally sound control of infectious diseases. Probiotics have shown beneficial effects on fish growth, nutrient metabolism, immune responses, disease prevention and control, and gut microbiota with higher water quality. However, the identification and characterization of the molecules and mechanisms associated with probiotics is a challenge that requires investigation. To address this challenge, herein we used the zebrafish model for the study of the efficacy and mechanisms of probiotic interventions against tuberculosis. First, bacteria from fish gut microbiota were identified with high content of the surface glycotope Galα1-3Galβ1-(3)4GlcNAc-R (α-Gal) that has been shown to induce protective immune responses. The results showed that probiotics of selected bacteria with high α-Gal content, namely Aeromonas veronii and , were biosafe and effective for the control of Mycobacterium marinum. Protective mechanisms regulating immunity and metabolism activated in response to α-Gal and probiotics with high α-Gal content included modification of gut microbiota composition, B-cell maturation, anti-α-Gal antibodies-mediated control of mycobacteria, induced innate immune responses, beneficial effects on nutrient metabolism and reduced oxidative stress. These results support the potential of probiotics with high -Gal content for the control of fish mycobacteriosis and suggested the possibility of exploring the development of combined probiotic treatments alone and in combination with -Gal for the control of infectious diseases.
PubMed: 34208966
DOI: 10.3390/ph14070635 -
Biomedicines Jun 2023The increased prevalence of disease, mortality, and antibiotic resistance among aquatic microorganisms has renewed interest in non-conventional disease prevention and...
The increased prevalence of disease, mortality, and antibiotic resistance among aquatic microorganisms has renewed interest in non-conventional disease prevention and control approaches. Nanoparticles present several benefits in aquaculture and hold significant potential for controlling both human and animal infections. This study reports on the antibacterial properties of green copper oxide nanoparticles (CuO NPs) synthesized from the urine of Mithun (MU) (). In addition, an array of analytical techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-visible spectroscopy (UV), and Fourier transform infrared spectroscopy (FTIR), were employed to investigate the synthesized MU-CuO nanoparticles. and , two bacterial fish pathogens known to cause severe infectious diseases in fish, were tested for their antibacterial efficacy against MU-CuO NPs. At 100 µg/mL, MU-CuO NPs exhibit enhanced antibacterial efficacy against two bacterial pathogens commonly found in fish. Applications in aquaculture may be looked at given that MU-CuO NPs showed greater antibacterial activity.
PubMed: 37371785
DOI: 10.3390/biomedicines11061690 -
Ecotoxicology and Environmental Safety Aug 2021Cherax quadricarinatus is a type of large freshwater crayfish that is characterized by rapid growth and formidable adaptability. It has also been widely cultured and...
A new insight to characterize immunomodulation based on hepatopancreatic transcriptome and humoral immune factor analysis of the Cherax quadricarinatus infected with Aeromonas veronii.
Cherax quadricarinatus is a type of large freshwater crayfish that is characterized by rapid growth and formidable adaptability. It has also been widely cultured and studied as a model organism. Aeromonas veronii is the dominant pathogen in aquatic environments and the primary threat to aquaculture's economic stability. To better understand the interactions between C. quadricarinatus and A. veronii, high-throughput RNA sequencing of the C. quadricarinatus hepatopancreas was carried out on a control group, susceptible group (6 h after infection), and resistant group (48 h after infection). A total of 65,850,929 genes were obtained. Compared with the control group, 2616 genes were up-regulated and 1551 genes were down-regulated in the susceptible group; while 1488 genes were up-regulated and 1712 genes were down-regulated in the resistant group. GO and KEGG analysis showed that these differentially expressed genes (DEGs) were associated with multiple immune pathways, including Toll-like receptors (TLRs), antigen processing and presentation, NOD-like receptor signaling pathway, phagosome, lysosome, JAK-STAT signaling pathway. qRT-PCR showed that infection by A. veronii changed the expression pattern of the serine proteinase inhibitor (SPI), crustacean hyperglycemic hormone (CHH), anti-lipopolysaccharide factor (ALF), and extracellular copper/zinc superoxide dismutase (SOD1), all of which were significantly higher than in the control group up to 48 h after infection. In addition, detection of superoxide dismutase (SOD), catalase (CAT), lysozyme (LZM), and phenoloxidase (PO) activity, as well as ceruloplasmin (CP) concentration at different times after infection showed diverse trends. Furthermore, pathological sections obtained 24 h after infection show lesions on the hepatopancreas and intestinal tissues caused by A. veronii. The results of this study provide a foundation for analyzing the immune mechanism of C. quadricarinatus infected with A. veronii at the transcriptional level and a theoretical basis for screening disease-resistant individuals to ensure healthy economic development of the aquatic industry.
Topics: Aeromonas veronii; Animals; Astacoidea; Factor Analysis, Statistical; Gram-Negative Bacterial Infections; Hepatopancreas; High-Throughput Nucleotide Sequencing; Immunologic Factors; Immunomodulation; Toll-Like Receptors; Transcriptome
PubMed: 34044307
DOI: 10.1016/j.ecoenv.2021.112347 -
Pathogens (Basel, Switzerland) Aug 2023Brazil is one of the world's leading producers of Nile tilapia, . However, the industry faces a major challenge in terms of infectious diseases, as at least five new...
Brazil is one of the world's leading producers of Nile tilapia, . However, the industry faces a major challenge in terms of infectious diseases, as at least five new pathogens have been formally described in the last five years. species are Gram-negative anaerobic bacteria that are often described as fish pathogens causing Motile Aeromonas Septicemia (MAS). In late December 2022, an epidemic outbreak was reported in farmed Nile tilapia in the state of São Paulo, Brazil, characterized by clinical signs and gross pathology suggestive of MAS. The objective of this study was to isolate, identify, and characterize in vitro and in vivo the causative agent of this epidemic outbreak. The bacterial isolates were identified as based on the homology of 16S rRNA (99.9%), (98.9%), and the gene (99.1%). showed susceptibility only to florfenicol, while it was resistant to the other three antimicrobials tested, oxytetracycline, enrofloxacin, and amoxicillin. The lowest florfenicol concentration capable of inhibiting bacterial growth was ≤0.5 µg/mL. The phenotypic resistance of the isolate observed for quinolones and tetracycline was genetically confirmed by the presence of the ( plasmid) and antibiotic-resistant genes, respectively. isolate was highly pathogenic in juvenile Nile tilapia tested in vivo, showing a mortality rate ranging from 3 to 100% in the lowest (1.2 × 10) and highest (1.2 × 10) bacterial dose groups, respectively. To our knowledge, this study would constitute the first report of highly pathogenic and multidrug-resistant associated with outbreaks and high mortality rates in tilapia farmed in commercial net cages in Brazil.
PubMed: 37623980
DOI: 10.3390/pathogens12081020 -
Pathogens (Basel, Switzerland) Dec 2022Bacterial communities, microbial populations, and antibiotic resistance of potential pathogens in the water and fish (, flesh and gut) from different areas (A1, A2 and...
Bacterial communities, microbial populations, and antibiotic resistance of potential pathogens in the water and fish (, flesh and gut) from different areas (A1, A2 and A3-A1 was linked with river water, A2 with cattle activity, and A3 with waters of a spring after heavy rains) of Lake Karla (Thessaly, Central Greece) were investigated. The isolated bacteria were identified using Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and were tested for resistance in 21 antibiotics. The microbiota composition of fish flesh was also studied using 16S amplicon-based sequencing and several species of (e.g., , , etc.) exhibited the highest abundances in all studied samples, while the microbiota profile between the three studied areas was similar, according to the culture-dependent analysis. Of them, was found to be resistant in the majority of the antibiotics for the water and fish (gut and flesh), mainly of the areas A1 and A2. Regarding 16S metabarcoding, the presence of and at genus level was confirmed, but they found at very lower abundances than those reported using the culture-dependent analysis. Finally, the TVC and the rest of the studied microbiological parameters were found at acceptable levels (4 log cfu/mL or cfu/g and 2-4 log cfu/mL or cfu/g, extremely low levels of /coliforms) in both water and fish flesh. Based on our findings, the water of Lake Karla would be used for activities such as irrigation, recreation and fishing, however, the development and implementation of a quality management tool for Lake Karla, to ensure environmental hygiene and prevention of zoonosis during the whole year, is imperative.
PubMed: 36558807
DOI: 10.3390/pathogens11121473