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Aquaculture International : Journal of... 2023This study aimed to develop and evaluate live and inactivated vaccines to pathogenicity in Nile tilapia. Therefore, five well-identified isolates, including A (HY1), A...
This study aimed to develop and evaluate live and inactivated vaccines to pathogenicity in Nile tilapia. Therefore, five well-identified isolates, including A (HY1), A (HY2), A (HY3), A (HY4), and A (HY6) isolated from diseased Nile tilapia (), were used for vaccine preparation. Virulence genes detected by a polymerase chain reaction (PCR) and lethal dose determination were conducted. Nile tilapia, each with a body weight of 25 ± 0.5 g were divided into six experimental groups (each of 20): T1 group (control), fish were injected with saline as a negative control, T2 group (formalin-killed vaccine) for the A (HY2) strain, T3 group ( formalized killed vaccine) for the A (HY4), T4 group (autoclaved vaccine) for the A (HY2), T5 group (autoclaved vaccine) for A (HY4), and T6 (live vaccine) for A (HY1), triplicate. At the end of the immunization period, all groups were challenged by , A (HY2). Blood samples were drawn 21 days post-immunization and 3 days after the challenge test for antibody titer assay. The results showed that the pathogenicity of strains A (HY2) and A (HY4) was the strongest, as the lethality rates (LR) were 100% and 90%, respectively, whereas the pathogenicity was moderate for strains A (HY3) and A (HY6) (LR 60% for each). A (AY1) was the weakest strain as no dead fish was found for this strain. The presence of , and genes as the main cause of the pathogenesis. The best protective efficacy was obtained from the live vaccine, A (HY1) with a protective rate of about 94.12% (relative percentage of survival, RPS), compared to autoclaved killed vaccines and formalin-killed vaccines. Based on immunoglobulin estimation (IgM) and RPS%, our data concluded that A (HY1) live vaccine had the best vaccine prophylactic effect against the highly pathogenic strain A(HY2).
PubMed: 36439703
DOI: 10.1007/s10499-022-01023-1 -
Antibiotics (Basel, Switzerland) Jun 2023is a Gram-negative bacterial species that causes disease in fish and is nowadays increasingly recurrent in enteric infections of humans. This study was performed to...
is a Gram-negative bacterial species that causes disease in fish and is nowadays increasingly recurrent in enteric infections of humans. This study was performed to characterize newly sequenced isolates by comparing them with complete genomes deposited at the NCBI (National Center for Biotechnology Information). Nine isolates from fish, environments, and humans from the São Francisco Valley (Petrolina, Pernambuco, Brazil) were sequenced and compared with complete genomes available in public databases to gain insight into taxonomic assignment and to better understand virulence and resistance profiles of this species within the One Health context. One local genome and four NCBI genomes were misidentified as . A total of 239 virulence genes were identified in the local genomes, with most encoding adhesion, motility, and secretion systems. In total, 60 genes involved with resistance to 22 classes of antibiotics were identified in the genomes, including and . The results suggest that the use of methods such as ANI is essential to avoid misclassification of the genomes. The virulence content of from local isolates is similar to those complete genomes deposited at the NCBI. Genes encoding colistin resistance are widespread in the species, requiring greater attention for surveillance systems.
PubMed: 37370358
DOI: 10.3390/antibiotics12061039 -
International Journal of Molecular... Feb 2020is a virulent fish pathogen that causes extensive economic losses in the aquaculture industry worldwide. In this study, a virulent strain of TH0426 was used to... (Comparative Study)
Comparative Study
is a virulent fish pathogen that causes extensive economic losses in the aquaculture industry worldwide. In this study, a virulent strain of TH0426 was used to establish an in vitro biofilm model. The results show that the biofilm-forming abilities of TH0426 were similar in different media, peaking under conditions of 20 °C and pH 6. Further, isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomics methods were used to compare the differential expression of between the biofilm and planktonic cells. The results show alterations in 277 proteins, with 130 being upregulated and 147 downregulated. Pathway analysis and GO (Gene Ontology) annotations indicated that these proteins are mainly involved in metabolic pathways and the biosynthesis of secondary metabolites and antibiotics. These proteins are the main factors affecting the adaptability of to its external environment. MRM (multiple reaction 27 monitoring) and qPCR (qPCR) were used to verify the differential proteins of the selected . This is the first report on the biofilm and planktonic cells of , thus contributing to studying the infection and pathogenesis of
Topics: Aeromonas veronii; Bacterial Proteins; Biofilms; Gene Expression Regulation, Bacterial; Proteomics
PubMed: 32093365
DOI: 10.3390/ijms21041450 -
Veterinary Microbiology Aug 2023Aeromonas veronii is a Gram-negative opportunistic bacterium found in fish, poultry and humans and has occasionally been associated with disease although not generally...
Aeromonas veronii is a Gram-negative opportunistic bacterium found in fish, poultry and humans and has occasionally been associated with disease although not generally considered a poultry pathogen. A. veronii was recently isolated from both healthy and condemned broiler carcasses at a major Danish abattoir. In this study, we did a whole genomic analysis of 24A. veronii strains from the abattoir to determine their potential sources and relatedness as well as their pathogenic potential, antimicrobial resistance determinants and associated mobile elements. No strains were multi-drug resistant, but all strains carried the beta-lactam resistance genes cphA3 and bla without being phenotypically resistant to carbapenems. One strain carried an IncA plasmid with tet(A), tet(B) and tet(E) genes. A phylogenetic tree including public A. veronii sequences showed that our isolates were not clonal but were dispersed around the phylogenetic tree, suggesting a diffuse spread of A. veronii across human, aquatic and poultry samples. Strains carried different virulence factors known to be associated with pathogenesis and severity of disease in animals and humans, e.g. type II (aerolysin, amylases, proteases, and cytotoxic enterotoxin Act) and III secretion systems where the latter has been associated with mortality in hospitalized patients. Although our genomic analysis of A. veronii shows zoonotic potential, epidemiological studies of human gastro-enteritis cases of A. veronii associated with consumption of broiler meat are needed. It remains to be proven if A. veronii is a true poultry pathogen and part of the established microflora in abattoirs and the gut-intestinal microflora of poultry.
Topics: Humans; Animals; Aeromonas veronii; Aeromonas; Chickens; Virulence; Phylogeny; Genomics; Denmark; Gram-Negative Bacterial Infections
PubMed: 37207528
DOI: 10.1016/j.vetmic.2023.109772 -
International Journal of Molecular... Sep 2022Yellow catfish () is an important aquaculture fish susceptible to infection, which causes acute death resulting in huge economic losses. Understanding the molecular...
Yellow catfish () is an important aquaculture fish susceptible to infection, which causes acute death resulting in huge economic losses. Understanding the molecular processes of host immune defense is indispensable to disease control. Here, we conducted the integrated and comparative analyses of the transcriptome and metabolome of yellow catfish in response to infection at the invaded stage and recovering stage. The crosstalk between -induced genes and metabolites uncovered the key biomarkers and pathways that strongest contribute to different response strategies used by yellow catfish at corresponding defense stages. We found that at the invading stage, the immune defense was strengthened by synthesizing lipids with energy consumption to repair the skin defense line and accumulate lipid droplets promoting intracellular defense line; triggering an inflammatory response by elevating cytokine IL-6, IL-10 and IL-1β following PAMP-elicited mitochondrial signaling, which was enhanced by ROS produced by impaired mitochondria; and activating apoptosis by up-regulating caspase 3, 7 and 8 and Prostaglandin F1α, meanwhile down-regulating FoxO3 and BCL6. Apoptosis was further potentiated via oxidative stress caused by mitochondrial dysfunction and exceeding inflammatory response. Additionally, cell cycle arrest was observed. At the fish recovering stage, survival strategies including sugar catabolism with D-mannose decreasing; energy generation through the TCA cycle and Oxidative phosphorylation pathways; antioxidant protection by enhancing Glutathione (oxidized), Anserine, and α-ketoglutarate; cell proliferation by inducing Cyclin G2 and CDKN1B; and autophagy initiated by FoxO3, ATG8 and ATP6V1A were highlighted. This study provides a comprehensive picture of yellow catfish coping with infection, which adds new insights for deciphering molecular mechanisms underlying fish immunity and developing stage-specific disease control techniques in aquaculture.
Topics: Aeromonas veronii; Animals; Catfishes; Fish Diseases; Fish Proteins; Metabolome; Transcriptome
PubMed: 36077519
DOI: 10.3390/ijms231710121 -
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 -
Microbiology Spectrum Jun 2022KPC-24, different from KPC-2 by a single amino acid alteration at codon 6 (R6P), was initially discovered in Klebsiella pneumoniae in Chile. Here, we reported...
KPC-24, different from KPC-2 by a single amino acid alteration at codon 6 (R6P), was initially discovered in Klebsiella pneumoniae in Chile. Here, we reported KPC-24-producing Aeromonas veronii isolates from hospital sewage in China. The was cloned and the MICs were tested against β-lactams antimicrobial agents. KPC-24 exhibited a β-lactam susceptibility profile similar to that of KPC-2. Whole-genome sequencing and analysis revealed that was located within a Tn-related region on an IncP-6 plasmid. Our study described a variant of K. pneumoniae carbapenemase (KPC), KPC-24, from two A. veronii strains isolated from hospital sewage, in which antibiotics, biocides, pharmaceuticals, and heavy metals may supply an appropriate condition for the evolution of carbapenemases. Some variants exhibited stronger hydrolysis activity to antibiotics and gave rise to a major public health concern. More seriously, species are prevalent in aquatic environments and, thus, may act as a suitable vector for antibiotics-resistance genes and foster the transmission of resistance. We should attach importance to surveying the evolution and transmission of antibiotics-resistance genes.
Topics: Aeromonas veronii; Anti-Bacterial Agents; Bacterial Proteins; Hospitals; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Plasmids; Sewage; beta-Lactamases
PubMed: 35546572
DOI: 10.1128/spectrum.00555-22 -
Microbiology Spectrum Aug 2022Mobile genetic elements contribute to the emergence and spread of multidrug-resistant bacteria by enabling the horizontal transfer of acquired antibiotic resistance...
Mobile genetic elements contribute to the emergence and spread of multidrug-resistant bacteria by enabling the horizontal transfer of acquired antibiotic resistance among different bacterial species and genera. This study characterizes the genetic backbone of in spp. and Klebsiella spp. isolated from untreated hospital effluents. Plasmids ranging in size from 9 to 244 kb, sequenced using Illumina and Nanopore platforms, revealed representatives of plasmid incompatibility groups IncP6, IncQ1, IncL/M1, IncFII, and IncFII-FIA. Different GES enzymes (GES-1, GES-7, and GES-16) were located in novel class 1 integrons in spp. and GES-5 in previously reported class 1 integrons in Klebsiella spp. Furthermore, in Klebsiella quasipneumoniae, was found in tandem as a coding sequence that disrupted the 3' conserved segment (CS). In Klebsiella grimontii, was observed in two different plasmids, and one of them carried multiple IncF replicons. Three Aeromonas caviae isolates presented , one Aeromonas veronii isolate presented , and another A. veronii isolate presented . Multilocus sequence typing (MLST) analysis revealed novel sequence types for and Klebsiella species. The current findings highlight the large genetic diversity of these species, emphasizing their great adaptability to the environment. The results also indicate a public health risk because these antimicrobial-resistant genes have the potential to reach wastewater treatment plants and larger water bodies. Considering that they are major interfaces between humans and the environment, they could spread throughout the community to clinical settings. In the "One Health" approach, which encompasses human, animal, and environmental health, emerging issues of antimicrobial resistance are associated with hospital effluents that contain clinically relevant antibiotic-resistant bacteria along with a wide range of antibiotic concentrations, and lack regulatory status for mandatory prior and effective treatment. genes have been reported in aquatic environments despite the low detection of these genes among clinical isolates within the studied hospitals. Carbapenemase enzymes, which are relatively unusual globally, such as GES type inserted into new integrons on plasmids, are worrisome. Notably, K. grimontii, a newly identified species, carried two plasmids with , and K. quasipneumoniae carried two copies of at the same plasmid. These kinds of plasmids are primarily responsible for multidrug resistance among bacteria in both clinical and natural environments, and they harbor resistant genes against antibiotics of key importance in clinical therapy, possibly leading to a public health problem of large proportion.
Topics: Aeromonas; Animals; Anti-Bacterial Agents; Drug Resistance, Multiple, Bacterial; Genetic Variation; Hospitals; Humans; Klebsiella pneumoniae; Microbial Sensitivity Tests; Multilocus Sequence Typing; Plasmids; beta-Lactamases
PubMed: 35880869
DOI: 10.1128/spectrum.02469-21 -
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 -
Pathogens (Basel, Switzerland) Dec 2022Efforts to combat antimicrobial resistance (AMR) should be based on the One Health approach, involving human health, animal health, and the environment. In Ghana,...
BACKGROUND
Efforts to combat antimicrobial resistance (AMR) should be based on the One Health approach, involving human health, animal health, and the environment. In Ghana, previous studies on AMR have given little attention to animal source food, a major route of transmission of antibiotic-resistant zoonotic pathogens. The aim of this study was to investigate the occurrence of multidrug-resistant (MDR) bacteria in meat sold in Accra.
METHODS
This was a cross-sectional study in which 270 meat samples (90 each of beef, goat meat, and chicken) were collected, and investigated for contamination with multidrug-resistant bacteria. The bacteria were subjected to susceptibility testing against amikacin (30 µg), ampicillin (10 µg), amoxicillin-clavulanate (20/10 µg), cefuroxime (30 µg), ceftriaxone (30 µg), ceftazidime (30 µg), cefepime (30 µg), ciprofloxacin (5 µg), trimethoprim-sulfamethoxazole (1.25/23.75 µg), ertapenem (10 µg), meropenem (10 µg), imipenem (10 µg), tigecycline (15 µg), and gentamicin (10 µg).
RESULTS
Thirty-two different types of bacteria, totalling 558, were isolated, the predominant being (44.6%), (19.9%), (3.4%), (3.2%), and (3.1%). The prevalence of MDR among the contaminating bacteria was 14.9%. The MDR distribution among the predominant bacteria was (18.7%), (11.1%), and (0.0% each), and (5.6%). Moreover, 2.0% of the contaminating bacteria were extended-spectrum beta-lactamase (ESBL) producers, all of which occurred in the chicken samples, and their distribution was: (1.3%), , spp., , and (0.2% each).
CONCLUSIONS
The meat samples were heavily contaminated with and , and less frequently, with , , and other organisms. The prevalence of multidrug-resistant bacteria was moderate (14.9%), while that of ESBL producers was low (2%).
PubMed: 36558851
DOI: 10.3390/pathogens11121517