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Fish & Shellfish Immunology Sep 2022Among aquaculture vaccines, polyvalent vaccines (for immunoprotection against multiple bacterial species) are more efficient and can better avoid bacterial resistance...
Among aquaculture vaccines, polyvalent vaccines (for immunoprotection against multiple bacterial species) are more efficient and can better avoid bacterial resistance and antibiotic residues in fish. Here, 15 outer membrane proteins (OMPs) of Aeromonas hydrophila were cloned and purified, and mouse antisera were prepared. Passive immunization to Carassius auratus showed that four OMPs sera (OmpW, OmpAII, P5, and AHA2685) and the entire OMPs serum held effective immunoprotection against A. hydrophila infection. Furthermore, the active immunization of four OMPs to C. auratus showed that OmpW, OmpAII, P5, and AHA2685 held effective immunoprotection against A. hydrophila, and OmpW held active cross-protection against Vibrio alginolyticus. The mechanisms of these four candidate vaccines in triggering immune responses were subsequently explored. They all could activate innate immune responses in active immunization, down-regulate (p < 0.05) the inflammation-related genes expression to reduce the inflammatory reaction induced by A. hydrophila, and down-regulate (p < 0.05) antioxidant-related factors to reduce the antioxidant reaction for bacterial infection. Noteablely, the four OMPs had protective abilities on kidney and spleen tissues of C. auratus after challenged with A. hydrophila and V. alginolyticus by histopathological observation. Collectively, our results identify OmpW as a polyvalent vaccine candidate, and OmpAII, P5, and AHA2685 as vaccine candidates against A. hydrophila infection in fish.
Topics: Aeromonas hydrophila; Animals; Anti-Bacterial Agents; Antigens, Bacterial; Antioxidants; Bacterial Outer Membrane Proteins; Bacterial Vaccines; Carps; Fish Diseases; Gram-Negative Bacterial Infections; Immune Sera; Mice; Vaccines, Combined
PubMed: 35926820
DOI: 10.1016/j.fsi.2022.07.057 -
Brazilian Journal of Biology = Revista... 2022Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani...
Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani fish but information related to the causative agents is not well-known. Keeping in view the significance of bacterial pathogens as the causative agents of multiple fish diseases, the present study was conducted for identification, characterization and analysis of virulence genes of Aeromonas spp. isolated from diseased fishes. A total of fifty fish samples having multiple clinical indications were collected from different fish farms of district Kasur, Punjab Pakistan. For isolation of Aeromonas spp. samples were enriched and inoculated on Aeromonas isolation medium. Isolates were identified and characterized by different biochemical tests, Analytical Profile Index (API) 20E kit and Polymerase Chain Reaction (PCR) assays. All isolates were screened for three putative virulence genes including aerolysin (aer), haemolysin (hyl) and heat labile cytotonic enterotoxin (alt). Seven isolates of Aeromonas (A.) hydrophila were retrieved and identified based on API 20E. These isolates were further confirmed as A. hydrophila on the basis of PCR assays. Three isolates were detected positive for the presence of virulence genes (alt and hyl). Whereas aerolysin (aer) gene was not present in any of A. hydrophila isolates. The present study confirmed A. hydrophila as the causative agent of epizootic ulcerative syndrome and motile Aeromonas septicemia in fish farms of district Kasur, Punjab Pakistan. Moreover, detection of two virulence genes (alt and hyl) in A. hydrophila isolates is a threat for fish consumers of study area.
Topics: Aeromonas; Aeromonas hydrophila; Animals; Enterotoxins; Fishes; Gram-Negative Bacterial Infections; Pakistan
PubMed: 35019106
DOI: 10.1590/1519-6984.254816 -
BMC Research Notes Nov 2023Eel (Anguilla bicolor bicolor) is an Indonesian export commodity. However, it is facing a problem related to Aeromonas hydrophila, which can cause motile aeromonas...
The potential of shallot skin powder and actinomycetes metabolites as antimicrobe and antibiofilm in the treatment of eel (Anguilla bicolor bicolor) infected with Aeromonas hydrophila.
BACKGROUND
Eel (Anguilla bicolor bicolor) is an Indonesian export commodity. However, it is facing a problem related to Aeromonas hydrophila, which can cause motile aeromonas septicemia (MAS) and produce biofilm formation. Problem with antibiotic resistance challenges the need of an alternative treatment. Therefore, it is important to explore a solution to treat infection and the biofilm formed by A. hydrophila.
OBJECTIVES
In this study, we used shallot skin powder and actinomycetes metabolite 20 PM as antimicrobe and antibiofilm to treated eels infected with A. hydrophila.
RESULTS
Shallot skin powder (6.25 g 100 g feed) and Actinomycetes 20 PM metabolite (2 mL 100 g feed) were found to be effective as antimicrobe and antibiofilm agent in treating eels infected with A. hydrophila. Eel treated with antibiotic, shallot skin powder, and actinomycetes metabolite had 80%, 66%, and 73% survival rates, respectively. Other indicators such as red blood cell count, hemoglobin, and hematocrit were increased, but white blood cell count and phagocytic activity were dropped. Biofilm destruction were analyzed using scanning electron microscopy to determined antibiofilm activity of actinomycetes metabolite against biofilm of A. Hydrophila.
CONCLUSIONS
Shallot skin powder and actinomycetes metabolite were potential to treat infection of A. hydrophila in eel as an alternative treatment to antibiotics.
Topics: Animals; Anguilla; Aeromonas hydrophila; Powders; Shallots; Actinobacteria; Actinomyces; Biofilms; Gram-Negative Bacterial Infections
PubMed: 37946241
DOI: 10.1186/s13104-023-06611-9 -
BMC Microbiology Jan 2021Hypervirulent Aeromonas hydrophila (vAh) is an emerging pathogen in freshwater aquaculture that results in the loss of over 3 million pounds of marketable channel...
BACKGROUND
Hypervirulent Aeromonas hydrophila (vAh) is an emerging pathogen in freshwater aquaculture that results in the loss of over 3 million pounds of marketable channel catfish, Ictalurus punctatus, and channel catfish hybrids (I. punctatus, ♀ x blue catfish, I. furcatus, ♂) each year from freshwater catfish production systems in Alabama, U.S.A. vAh isolates are clonal in nature and are genetically unique from, and significantly more virulent than, traditional A. hydrophila isolates from fish. Even with the increased virulence, natural infections cannot be reproduced in aquaria challenges making it difficult to determine modes of infection and the pathophysiology behind the devastating mortalities that are commonly observed. Despite the intimate connection between environmental adaptation and plastic response, the role of environmental adaption on vAh pathogenicity and virulence has not been previously explored. In this study, secreted proteins of vAh cultured as free-living planktonic cells and within a biofilm were compared to elucidate the role of biofilm growth on virulence.
RESULTS
Functional proteolytic assays found significantly increased degradative activity in biofilm secretomes; in contrast, planktonic secretomes had significantly increased hemolytic activity, suggesting higher toxigenic potential. Intramuscular injection challenges in a channel catfish model showed that in vitro degradative activity translated into in vivo tissue destruction. Identification of secreted proteins by HPLC-MS/MS revealed the presence of many putative virulence proteins under both growth conditions. Biofilm grown vAh produced higher levels of proteolytic enzymes and adhesins, whereas planktonically grown cells secreted higher levels of toxins, porins, and fimbrial proteins.
CONCLUSIONS
This study is the first comparison of the secreted proteomes of vAh when grown in two distinct ecological niches. These data on the adaptive physiological response of vAh based on growth condition increase our understanding of how environmental niche partitioning could affect vAh pathogenicity and virulence. Increased secretion of colonization factors and degradative enzymes during biofilm growth and residency may increase bacterial attachment and host invasiveness, while increased secretion of hemolysins, porins, and other potential toxins under planktonic growth (or after host invasion) could result in increased host mortality. The results of this research underscore the need to use culture methods that more closely mimic natural ecological habitat growth to improve our understanding of vAh pathogenesis.
Topics: Aeromonas hydrophila; Alabama; Animals; Aquaculture; Bacterial Proteins; Bacteriological Techniques; Biofilms; Chromatography, High Pressure Liquid; Fish Diseases; Gram-Negative Bacterial Infections; Ictaluridae; Plankton; Proteomics; Tandem Mass Spectrometry; Virulence; Whole Genome Sequencing
PubMed: 33407117
DOI: 10.1186/s12866-020-02065-2 -
Virulence Dec 2021() can cause a number of diseases in both human and animals. related infections in aquaculture cause severe economic losses every year throughout the world. The...
() can cause a number of diseases in both human and animals. related infections in aquaculture cause severe economic losses every year throughout the world. The emergence of antibiotic resistance that is due to the abuse of antibiotics has limited the application of antibiotics. Thus, novel approaches are needed to combat with treatment failure of antibiotics caused by resistant bacterial strains. Aerolysin plays a critical role in the pathogenesis of and has been considered as a novel target for developing drugs based on anti-virulence strategies. Here, we reported that luteolin, a natural product with no anti- activity, could reduce aerolysin-induced hemolysis by inhibiting aerolysin activity. The binding mode was simulated by molecular docking and dynamics simulation. Then the main binding sites were confirmed by fluorescence quenching assays. We found that luteolin could hindered the formation of functional heptamer of aerolysin according to the results of the oligomerization assay. Moreover, luteolin could protect A549 cells from aerolysin mediated cell death and increase the survival rate of -infected channel catfish. These findings suggest a novel approach to developing drugs fighting against , and luteolin can be a promising drug candidate for treatment of -associated infections.
Topics: A549 Cells; Aeromonas hydrophila; Animals; Bacterial Toxins; Biological Products; Carps; Fish Diseases; Humans; Luteolin; Molecular Docking Simulation; Pore Forming Cytotoxic Proteins; Virulence
PubMed: 33372840
DOI: 10.1080/21505594.2020.1867455 -
PeerJ 2023Tilapia is a primary aquaculture fish in Thailand, but little is known about the occurrence of antimicrobial resistance (AMR) in , spp., and colonizing healthy tilapia...
BACKGROUND
Tilapia is a primary aquaculture fish in Thailand, but little is known about the occurrence of antimicrobial resistance (AMR) in , spp., and colonizing healthy tilapia intended for human consumption and the co-occurrence of these AMR bacteria in the cultivation water.
METHODS
This study determined the phenotype and genotype of AMR, extended-spectrum -lactamase (ESBL) production, and virulence factors of , spp., and isolated from hybrid red tilapia and cultivation water in Thailand. Standard culture methods such as USFDA's BAM or ISO procedures were used for the original isolation, with all isolates confirmed by biochemical tests, serotyping, and species-specific gene detection based on PCR.
RESULTS
A total of 278 isolates consisting of 15 , 188 spp., and 75 isolates were retrieved from a previous study. All isolates of and isolates were resistance to at least one antimicrobial, with 26.7% and 72.3% of the isolates being multidrug resistant (MDR), respectively. All isolates were resistant to ampicillin (100%), followed by oxytetracycline (26.7%), tetracycline (26.7%), trimethoprim (26.7%), and oxolinic acid (20.0%). The predominant resistance genes in were (20.0%), followed by 13.3% of isolates having , , , , and isolates also exhibited a high prevalence of resistance to ampicillin (79.3%), oxolinic acid (75.5%), oxytetracycline (71.8%), chloramphenicol (62.8%), and florfenicol (55.3%). The most common resistance genes in these isolates were (65.4%), (64.9%), (63.8%), and (55.9%). All isolates were susceptible to all antimicrobials tested, while the most common resistance gene was (12.0%). One isolate of was positive for , while all isolates of and isolates were negative for integrons and . None of the bacterial isolates in this study were producing ESBL. The occurrence of (20.0%) in these isolates from tilapia aquaculture may signify a serious occupational and consumer health risk given that colistin is a last resort antimicrobial for treatment of Gram-negative bacteria infections.
CONCLUSIONS
Findings from this study on AMR bacteria in hybrid red tilapia suggest that aquaculture as practiced in Thailand can select for ubiquitous AMR pathogens, mobile genetic elements, and an emerging reservoir of and colistin-resistant bacteria. Resistant and pathogenic bacteria, such as resistance to ampicillin and tetracycline, or MDR circulating in aquaculture, together highlight the public health concerns and foodborne risks of zoonotic pathogens in humans from cultured freshwater fish.
Topics: Animals; Aeromonas hydrophila; Ampicillin; Anti-Bacterial Agents; Colistin; Drug Resistance, Bacterial; Oxolinic Acid; Oxytetracycline; Tetracycline; Tilapia; Virulence Factors
PubMed: 36855429
DOI: 10.7717/peerj.14896 -
Microscopy Research and Technique May 2022The present research was conducted to prepare efficient G-SPIONs by co-precipitation to remove Edwardsiella tarda and Aeromonas hydrophila from the aqueous solution. The...
Preparation and characterization of glucose-conjugated super-paramagnetic iron oxide nanoparticles (G-SPIONs) for removal of Edwardsiella tarda and Aeromonas hydrophila from water.
The present research was conducted to prepare efficient G-SPIONs by co-precipitation to remove Edwardsiella tarda and Aeromonas hydrophila from the aqueous solution. The synthesized G-SPIONs were characterized by UV-Vis spectrophotometer, DLS, FEG-TEM, FT-IR, XRD, and VSM analysis. The results showed that the synthesized G-SPIONs had super-paramagnetic properties (58.31 emu/g) and spherical shape (16 ± 3 nm). The antibacterial activity was assessed in sterilized distilled water at different G-SPIONs concentrations viz. 0, 1.5, 3, 6, 12, 24, 48, 120, and 240 mg/L against E. tarda and A. hydrophila with various bacterial loads viz. 1 × 10 , 1 × 10 , 1 × 10 , 1 × 10 , and 1 × 10 CFU/ml at different time intervals 15, 30, 45, and 60 min. At a lower bacterial load of E. tarda and A. hydrophila 1 × 10 -1 × 10 CFU/ml, 100% bacterial load was removed by 15 min exposure with NPs concentration 6-48 mg/L and 1.5-6 mg/L, respectively. Cent percent bacterial removal was observed in both the bacterial species even at higher bacterial load (1 × 10 -1 × 10 CFU/ml) by increasing exposure time (15-60 min) and nanoparticle concentration as well (24-240 mg/L). At an initial bacterial load of E. tarda and A. hydrophila (1 × 10 -1 × 10 CFU/ml), the EC ranged between 0.01-6.51 mg/L and 0.02-3.84 mg/L, respectively, after 15-60 min exposure. Thus, it is concluded that the antibacterial effect of G-SPIONs depends on concentration and exposure time. Hence, G-SPIONs can be used as an antibacterial/biocidal agent to treat Edwardsiellosis and Aeromonosis disease in aquaculture. HIGHLIGHTS: The glucose-conjugated super-paramagnetic iron oxide nanoparticles (G-SPIONs) synthesized by rapid and high yield co-precipitation method shows bacterial removal efficiency against Edwardsiella tarda and Aeromonas hydrophila The bacterial removal efficiency of G-SPIONs depends on concentration and exposure time to both the bacterial species The 100% bacterial removal efficiency can be achieved even at the highest bacterial load (1 × 10 CFU/ml) against E. tarda and A. hydrophila after 45 and 30 min exposure Due to the high bacterial removal efficiency of G-SPIONs against E. tarda and A. hydrophila, it can be used for the treatment of Edwardsiellosis and Aeromonosis in fish.
Topics: Aeromonas hydrophila; Animals; Anti-Bacterial Agents; Edwardsiella tarda; Fish Diseases; Glucose; Magnetic Iron Oxide Nanoparticles; Spectroscopy, Fourier Transform Infrared; Water
PubMed: 35038205
DOI: 10.1002/jemt.24037 -
Veterinary Research Communications Jun 2022Secretions of beneficial intestinal bacteria can inhibit the growth and biofilm formation of a wide range of microorganisms. Curcumin has shown broad spectrum...
Secretions of beneficial intestinal bacteria can inhibit the growth and biofilm formation of a wide range of microorganisms. Curcumin has shown broad spectrum antioxidant, anti-inflammatory, and antimicrobial potential. It is important to evaluate the influence of these secretions with bioactive peptides, in combination with curcumin, to limit growth and inhibit biofilm formation of pathogenic bacteria of importance in aquaculture. In the present study, the supernatants of Lactoccocus lactis NZ9000, Lactobacillus rhamnosus GG and Pediococcus pentosaceus NCDO 990, and curcumin (0,1,10,25 and 50 μM) were used to evaluate their efficacy in growth, inhibition biofilm and membrane permeability of Aeromonas hydrophila CAIM 347 (A. hydrophila). The supernatants of probiotics and curcumin 1,10 and 25 μM exerted similar effects in reducing the growth of A. hydrophila at 12 h of interaction. The supernatants of the probiotics and curcumin 25 and 50 μM exerted similar effects in reducing the biofilm of A. hydrophila. There is a significant increase in the membrane permeability of A. hydrophila in interaction with 50 μM curcumin at two hours of incubation and with the supernatants separately in the same period. Different modes of action of curcumin and bacteriocins separately were demonstrated as effective substitutes for antibiotics in containing A. hydrophila and avoiding the application of antibiotics. The techniques implemented in this study provide evidence that there is no synergy between treatments at the selected concentrations and times.
Topics: Aeromonas hydrophila; Animals; Anti-Bacterial Agents; Curcumin; Lacticaseibacillus rhamnosus; Lactococcus lactis; Pediococcus pentosaceus
PubMed: 34997440
DOI: 10.1007/s11259-021-09871-7 -
Microbial Pathogenesis Oct 2019Emergence of antibiotic resistant bacteria has necessitated the drive to explore competent antimicrobial agents or to develop novel formulations to treat infections...
Emergence of antibiotic resistant bacteria has necessitated the drive to explore competent antimicrobial agents or to develop novel formulations to treat infections including Aeromonas hydrophila. The present study investigates the synergistic antibacterial effects of citrus flavonoid rutin and florfenicol (FF) against A. hydrophila in vitro and in vivo. Rutin is extracted and purified from Citrus sinensis peel through preparative HPLC and characterized through TLC, GC-MS and H and C NMR analyses. Though rutin did not display significant antibacterial activity, it modulated FF activity resulting in four-fold reduction in the MIC value for FF. The anti-biofilm potential of synergistic association of rutin and FF was validated by protein analysis, quantification of exopolysaccharide (EPS) and microscopy studies using sub-MIC doses. Besides antibacterial action, in vivo studies showed that Rutin/FF combination enhanced host immunity by improving blood cell count, anti-protease, and lysozyme activities as well as decreased the oxidative stress and the pathological changes of tilapia Oreochromis niloticus against A. hydrophila infection. No significant DNA damages or clastogenic effects were detected in tilapia challenged with A. hydrophila under Rutin/FF treatment. It is shown that an acute-phase Lipopolysaccharide binding protein (LBP) enhances the innate host defence against bacterial challenge. Semi quantitative RT-PCR and western blot results revealed the significant increase of LBP in the supernatant of tilapia monocytes/macrophages challenged with A. hydrophila upon treatment. The study findings substantiate that the combination of natural molecules with antibiotics may open up possibilities to treat MDR strains.
Topics: Aeromonas hydrophila; Animals; Anti-Bacterial Agents; Biofilms; Citrus sinensis; DNA Damage; Disease Models, Animal; Drug Combinations; Drug Synergism; Fish Diseases; Fisheries; Gram-Negative Bacterial Infections; Immunity; Immunomodulation; India; Microbial Sensitivity Tests; Oxidative Stress; Plant Extracts; Rutin; Thiamphenicol; Tilapia; Virulence
PubMed: 31252064
DOI: 10.1016/j.micpath.2019.103612 -
Developmental and Comparative Immunology Apr 2022The endosialin family is the group XIV of C-type lectin, regulating several processes involved in innate immunity and inflammation. Endosialin family genes have been...
The endosialin family is the group XIV of C-type lectin, regulating several processes involved in innate immunity and inflammation. Endosialin family genes have been extensively studied in human and mammals, however, rarely reported in teleost. In the present study, a set of 8 endosialin family genes was identified across the entire common carp genome. Functional domain and motif prediction and phylogenetic analysis supported their annotation and orthologies. Through examining gene copy number across several vertebrates, endosialin family genes were found have undergone gene duplication. Most of the endosialin family genes were ubiquitously expressed during common carp early developmental stages, and presented tissue-specific expression patterns in various healthy tissues, with relatively high expression in intestine, liver, gill, spleen and kidney, indicating their likely essential roles in maintaining homeostasis and host immune response. After Aeromonas hydrophila infection, gene thbd-1, thbd-2 and cd93-2 were significantly up-regulated at one or more timepoints in spleen and kidney, while gene cd248a-1, cd248a-2, cd248b-1, cd248b-2, and cd93-1 were significantly down-regulated. Taken together, all these results suggested that endosialin family genes were involved in host immune response to A. hydrophila infection in common carp, and provided fundamental genomic resources for better understanding the critical roles of endosialin family on the primary innate immune processes in teleost.
Topics: Aeromonas hydrophila; Animals; Antigens, CD; Antigens, Neoplasm; Carps; Fish Diseases; Fish Proteins; Gene Dosage; Genome; Gram-Negative Bacterial Infections; Humans; Immunity, Innate; Lectins, C-Type; Phylogeny; Spleen
PubMed: 34995551
DOI: 10.1016/j.dci.2021.104338