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Antonie Van Leeuwenhoek Dec 2023Naturally infected Channa punctata exhibiting bacterial septicemic syndrome including ulcerations along with mortality records were collected from a fish farm in Assam...
Naturally infected Channa punctata exhibiting bacterial septicemic syndrome including ulcerations along with mortality records were collected from a fish farm in Assam during winter season (early November 2020 to early January 2021). The moribund fishes were subjected for bacterial isolation followed by identification of the bacteria. Two dominant emerging bacterial pathogens were identified as Aeromonas veronii (isolate ZooGURD-01) and Aeromonas hydrophila (isolate ZooGURD-05) by standard biochemical characterization and 16S rRNA and rpo B gene amplification. Re-infection experiments of both the bacterial isolates in healthy disease-free C. punctata showed similar symptoms to that of natural infection thus confirming their virulence. The LD calculated during challenge test for both the isolates ZooGURD-01 and ZooGURD-05 found to be pathogenic at 2.6 × 10 and 1.6 × 10 CFU/fish respectively. Further PCR amplification of specific virulent genes (aerolysin, hemolysin and enterotoxin) confirmed pathogenicity for both isolates. Histopathological examinations of liver and kidney in re-infection experiments showed prominent changes supporting bacterial septicaemia. Antibiotic sensitivity pattern showed that the isolates ZooGURD-01 and ZooGURD-05 were sensitive to 22 and 19 out of 25 antimicrobials respectively. The present study was the first report on the mortality of farmed C. punctata associated with natural infection caused by A. veronii and A. hydrophila with no record of pathogenicity of A. veronii in C. punctata.
Topics: Animals; Channa punctatus; Aeromonas hydrophila; Aeromonas veronii; RNA, Ribosomal, 16S; Reinfection; Fishes
PubMed: 38153571
DOI: 10.1007/s10482-023-01896-z -
Animals : An Open Access Journal From... Aug 2023The objective of this study was to understand biological characteristics of one bacteria strain named as VPG which was isolated from multiple organs of a dead captive...
The objective of this study was to understand biological characteristics of one bacteria strain named as VPG which was isolated from multiple organs of a dead captive giant panda cub. Here, we use biochemical tests, 16S rRNA and genes for bacterial identification, the disk diffusion method for antibiotic resistance phenotype, smart chip real-time PCR for the antibiotic resistance genotype, multiplex PCR for determination of virulence genes, and the acute toxicity test in mice for testing the pathogenicity of isolates. The isolate was identified as strain based on the biochemical properties and genetic analysis. We found that the strain carried 31 antibiotic resistance genes, revealed antimicrobial resistance phenotypically to several antibiotics including penicillin, ampicillin, oxacillin, amoxicillin, imipenem, and vancomycin, and carried virulence genes including , , , , , , and . The main pathological changes in giant panda were congestion, necrotic lesions and a large number of bacteria in multiple organs. In addition, the LD in Kunming mice infected with strain VGP was 5.14 × 10 CFU/mL by intraperitoneal injection. Infection with strain VGP led to considerable histological lesions such as hemorrhage of internal organs, necrosis of lymphocytes and neurons in Kunming mice. Taken together, these results suggest that infection with strain VGP would be an important causes of death in this giant panda cub.
PubMed: 37685043
DOI: 10.3390/ani13172779 -
Journal of Fish Diseases Oct 2017Diseases caused by motile aeromonads in freshwater fish have been generally assumed to be linked with mainly Aeromonas hydrophila while other species were probably...
Diseases caused by motile aeromonads in freshwater fish have been generally assumed to be linked with mainly Aeromonas hydrophila while other species were probably overlooked. Here, we identified two isolates of non-A. hydrophila recovered from Nile tilapia exhibiting disease and mortality after exposed to transport-induced stress and subsequently confirmed their virulence in artificial infection. The bacterial isolates were identified as Aeromonas jandaei and Aeromonas veronii based on phenotypic features and homology of 16S rDNA. Experimental infection revealed that the high dose of A. jandaei (3.7 × 10 CFU fish ) and A. veronii (8.9 × 10 CFU fish ) killed 100% of experimental fish within 24 h, while a 10-fold reduction dose killed 70% and 50% of fish, respectively. When the challenge dose was reduced 100-fold, mortality of the fish exposed to A. jandaei and A. veronii decreased to 20% and 10%, respectively. The survivors from the latter dose administration were rechallenged with respective bacterial species. Lower mortality of rechallenged fish (0%-12.5%) compared to the control groups receiving a primary infection (37.5%) suggested that the survivors after primary infection were able to resist secondary infection. Fish exposed to either A. jandaei or A. veronii exhibited similar clinical signs and histological manifestation.
Topics: Aeromonas; Aeromonas veronii; Animals; Cichlids; DNA, Bacterial; Fish Diseases; Gram-Negative Bacterial Infections; Phylogeny; RNA, Ribosomal, 16S; Stress, Physiological; Thailand; Transportation; Virulence
PubMed: 28383126
DOI: 10.1111/jfd.12617 -
Fish & Shellfish Immunology May 2022Currently, the intervention of plant by-products in the fish diet has gained tremendous attention owing to the economic and high nutritious value. The current study is a...
Immune-antioxidant trait, Aeromonas veronii resistance, growth, intestinal architecture, and splenic cytokines expression of Cyprinus carpio fed Prunus armeniaca kernel-enriched diets.
Currently, the intervention of plant by-products in the fish diet has gained tremendous attention owing to the economic and high nutritious value. The current study is a pioneer attempt to incorporate the apricot, Prunus armeniaca kernel powder (PAKP) into the Common carp, Cyprinus carpio diets, and assess its efficacy on growth, digestion, intestinal morphology, immunity, antioxidant capacity, and splenic cytokines expression, besides the antibacterial role against Aeromonas veronii infection. Apparently healthy fish (N = 120) with an initial body weight of 24.76 ± 0.03g were allotted in 12 glass aquaria (60 L) and randomly distributed into four groups (triplicates, 10 fish/aquarium). The control group (PAKP0) was fed a basal diet without additives. The second, third, and fourth groups were provided PAKP diets with various concentrations (2.5 (PAKP2.5), 5 (PAKP5), and 10 g kg (PAKP10)) respectively. After 60 days (feeding trial), sub-samples of the fish (12 fish/group) were intraperitoneally injected with 1 × 10 CFU mL of A. veronii. Results revealed that body weight gain, feed conversion ratio, and specific growth rates were significantly augmented in the PAKP10 group in comparison to the other groups. The dietary inclusion of PAKP at all concentrations boosted the digestive capacity and maintained the intestinal morphology (average villus length, villus width, and goblet cells count) with a marked improvement in PAKP10. Moreover, fish fed on PAKP10 followed by PAKP5 then PAKP2.5 diets had noticeably elevated values of immunological biomarkers (IgM, antiprotease, and lysozyme activity) and antioxidant capabilities (the total antioxidant capacity, superoxide dismutase, and reduced glutathione) as well as significant up-regulation of immune and antioxidant-related genes (TGF-β2, TLR-2, TNF-α, IL-10, SOD, GPx, and GSS). Fourteen days post-infection with A. veronii, the highest relative percentage survival of fish was observed in PAKP10 (83.33%), followed by PAKP5 (66.67%), and PAKP2.5 (50%). Our results indicated that a dietary intervention with PAKP could promise growth, digestion, immunity, and protect C. carpio against A. veronii infection in a dose-dependent manner. This offers a framework for future application of such seeds as a growth promotor, immune-stimulant, and antioxidant, besides an alternative cheap therapeutic antibacterial agent for sustaining the aquaculture industry.
Topics: Aeromonas veronii; Animal Feed; Animals; Antioxidants; Body Weight; Carps; Cytokines; Diet; Dietary Supplements; Disease Resistance; Fish Diseases; Gram-Negative Bacterial Infections; Plant Extracts; Prunus armeniaca
PubMed: 35398527
DOI: 10.1016/j.fsi.2022.03.048 -
Journal of Applied Microbiology Mar 2023Aeromonas species are bacterial pathogens that cause significant economic losses in the aquaculture industry worldwide. They are widely distributed in aquatic... (Review)
Review
Aeromonas species are bacterial pathogens that cause significant economic losses in the aquaculture industry worldwide. They are widely distributed in aquatic environments and cause several diseases in both humans and aquatic animals. The presence of various virulent Aeromonas spp. in aquatic environments predisposes infections in aquatic animals and humans. Concern about the transfer of pathogens from fish to humans also increased with the substantial increase in seafood consumption. Aeromonas spp. are also primary human pathogens that cause local and systemic infections, both in immunologically compromised and immunologically competent hosts. The most common Aeromonas spp. causing infections in aquatic animals and humans are A. hydrophila, A. salmonicida, A. caviae, and A. veronii biotype sobria. The ability of Aeromonas spp. to produce a variety of virulence factors enhances their pathogenic ability. Literature has supplied evidence for the presence of various virulence factors, including proteases, enterotoxins, hemolysin, and toxin genes of Aeromonas spp. in aquatic environments. The high prevalence of Aeromonas spp. in the aquatic environment is also a threat to public health. Because the Aeromonas spp. infections in humans are generally the result of ingestion or exposure to contaminated food and water. This review summarizes the recently published information on various virulence factors and virulence genes of Aeromonas spp. isolated from various aquatic environments, including seawater, freshwater, wastewater, and drinking water. It is also intended to highlight the risks associated with Aeromonas species' virulence properties for both aquaculture and public health.
Topics: Animals; Humans; Aeromonas; Virulence; Virulence Factors; Fishes; Enterotoxins
PubMed: 36809788
DOI: 10.1093/jambio/lxad031 -
Frontiers in Cellular and Infection... 2020Small protein B(SmpB) cooperates with transfer-messenger RNA (tmRNA) for -translation to ensure the quality control of protein synthesis in prokaryotes. Furthermore,...
Small protein B(SmpB) cooperates with transfer-messenger RNA (tmRNA) for -translation to ensure the quality control of protein synthesis in prokaryotes. Furthermore, they regulate cell metabolism separately. According to research, SmpB functions as a transcription factor, and tmRNA acts as a small RNA. Purine pathway has been reported to be related to trimethoprim resistance, including hypoxanthine synthesis, adenosine metabolism and guanosine metabolism. Another reason of drug tolerance is the efflux pump of the bacterium. In transcriptomic data, it was shown that the expression of some related enzymes in adenosine metabolism were raised significantly in deletion strain than that of wild type, which led to the differential trimethoprim resistance of (. Furthermore, the metabolic products of adenosine AMP, cAMP, and deoxyadenosine were accumulated significantly. However, the expressions of the enzymes related to hypoxanthine synthesis and guanosine metabolism were elevated significantly in , which eventually caused an augmented metabolic product xanthine. In addition, the deletion of also affected the significant downregulations of efflux pump . The minimal inhibitory concentrations (MIC) were overall decreased after the trimethoprim treatment to the wild type, Δ and Δ. And the difference in sensitivity between Δ and Δ was evident. The MIC of Δ was descended significantly than those of wild type and Δ in M9 medium supplemented with 1 mM adenosine, illustrating that the adenosine metabolism pathway was principally influenced by SmpB. Likewise, the strain Δ conferred more sensitivity than wild type and Δ in M9 medium supplemented with 1mM guanosine. By overexpressing /, the tolerance to trimethoprim was partially recovered in Δ. These results revealed that SmpB and tmRNA acted on different branches in purine metabolism, conferring the diverse trimethoprim resistance to . This study suggests that the -translation system might be an effective target in clinical treatment of and other multi-antibiotic resistance bacteria with trimethoprim.
Topics: Aeromonas veronii; Protein Biosynthesis; Purines; RNA, Bacterial; Trimethoprim Resistance
PubMed: 32547961
DOI: 10.3389/fcimb.2020.00239 -
Environmental Microbiology Sep 2018Aeromonas species are ubiquitous inhabitants of freshwater environments, and are responsible for fish motile aeromonad septicemia (MAS). A. hydrophila is implicated as...
Aeromonas species are ubiquitous inhabitants of freshwater environments, and are responsible for fish motile aeromonad septicemia (MAS). A. hydrophila is implicated as the primary etiologic agent of MAS. Here, we analysed MAS epidemiological data for cyprinid fish in southern China, and found that A. veronii infections dominated. Consistent with this observation, A. veronii isolates were generally more virulent than A. hydrophila isolates when infecting germ-free zebrafish larvae via continuous immersion challenge. Through in vivo screening of the transposon library of the A. veronii strain Hm091, aerolysin was identified as the key virulence factor. Further results indicated that A. veronii Hm091 aerolysin disrupts the intestinal barrier of zebrafish, enabling systematic invasion by not only A. veronii Hm091 in a mono-infection, but also A. hydrophila NJ-1 in a mixed infection. Moreover, the differences in aerolysin expression and activity were the major contributor to the observed differences between the A. veronii and A. hydrophila strains regarding invasion efficacy via intestine. Together, our results provide new insights into the aetiology and pathogenesis of Aeromonas infections, and highlight the importance of A. veronii-targeted treatments in future efforts against MAS.
Topics: Aeromonas; Aeromonas veronii; Animals; Bacterial Toxins; China; Fish Diseases; Gram-Negative Bacterial Infections; Pore Forming Cytotoxic Proteins; Sepsis; Virulence; Virulence Factors; Zebrafish
PubMed: 30136361
DOI: 10.1111/1462-2920.14390 -
Microbial Pathogenesis Apr 2018Virulent microbial pathogen infections are the main cause for amphibian decline worldwide. In the present study, a bacterial strain named RDL-2, which was isolated from...
First isolation and characterization of the pathogenic Aeromonas veronii bv. veronii associated with ulcerative syndrome in the indigenous Pelophylax ridibundus of Al-Ahsaa, Saudi Arabia.
Virulent microbial pathogen infections are the main cause for amphibian decline worldwide. In the present study, a bacterial strain named RDL-2, which was isolated from the skin of infected Pelophylax ridibundus larvae, was cultured and then phenotypically and biochemically characterized using scanning electron microscopic observations and the API20E strip and Biolog Gen III MicroPlate system. The 16S rRNA gene sequence of this strain was also obtained and used in strain identification and phylogenetic analysis. Healthy P. ridibundus larvae were challenged with RDL-2 and monitored to determine clinical signs consistent with the disease. Strain RDL-2 was identified as Aeromonas veronii based on its phenotypic and biochemical characteristics and on 16S rRNA gene sequence and phylogenetic analysis: RDL-2 was gram-negative, rod-shaped, and reacted positively for 69 (73%) of the 94 traits analysed; its 16S rRNA gene sequence displayed the highest homology to that of A. veronii bv. veronii (99.9%). Koch's postulates were fulfilled confirming that A. veronii is the causal agent of ulcerative syndrome. Thus, this study is the first to report A. veronii as a marsh frog pathogen in the Al-Ahsaa region. The aetiology of A. veronii as a potential poikilothermic pathogen shown here will expedite the development of diagnostic tests and methods for eradicating ulcerative syndrome.
Topics: Aeromonas veronii; Animal Diseases; Animals; DNA, Bacterial; Gram-Negative Bacterial Infections; Larva; Phylogeny; RNA, Ribosomal, 16S; Ranidae; Saudi Arabia; Species Specificity; Virulence
PubMed: 29038059
DOI: 10.1016/j.micpath.2017.10.019 -
Journal of Global Antimicrobial... Dec 2021Aeromonas veronii can cause infections in humans and a wide variety of aquatic and terrestrial animals as well as causing serious economic losses in aquaculture...
OBJECTIVES
Aeromonas veronii can cause infections in humans and a wide variety of aquatic and terrestrial animals as well as causing serious economic losses in aquaculture worldwide. Aeromonas veronii strain JC529 was isolated from an infected common carp in a fish pond in Jilin Province. In this study, we identified the multidrug resistance genes and traced the source of the strain in order to lay the foundation for research on the resistance mechanisms of other Aeromonas isolates.
METHODS
The isolated strain was sequenced using PacBio RS II and Illumina HiSeq 4000 platforms. Corrected reads were assembled using Celera and Falcon software and genes were predicted using Glimmer software. Seven databases were used for general function annotation. Virulence factors and resistance genes were identified based on the core data set in the VFDB and ARDB databases. Concurrently, 68 publicly available A. veronii genomes (including A. veronii JC529) were compared to reveal the clustering relationship of JC529.
RESULTS
Aeromonas veronii strain JC529 has a circular chromosome of 4 834 659 bp with a GC content of 59.64%, including 4264 protein-coding genes, 2 prophages, 482 virulence factors and 27 antibiotic resistance genes, indicating that strain JC529 is a multidrug-resistant strain. The phylogenetic tree showed that strains JC529 and NS, PDB, AG5.28.6 and VCK1 appear to be inherited from a common ancestor and affect aquaculture in China and Greece.
CONCLUSION
Strain JC529 is a multidrug-resistant A. veronii strain and has been inherited from a common ancestor with Greece.
Topics: Aeromonas veronii; Animals; Anti-Bacterial Agents; Carps; Drug Resistance, Bacterial; Gram-Negative Bacterial Infections; Humans; Phylogeny
PubMed: 34508865
DOI: 10.1016/j.jgar.2021.08.007 -
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