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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 -
PloS One 2024Aeromonas hydrophila is one of the major pathogenic bacteria responsible for causing severe outbreaks at fish farms and is also a major global public health concern....
Aeromonas hydrophila is one of the major pathogenic bacteria responsible for causing severe outbreaks at fish farms and is also a major global public health concern. This bacterium harbors many virulence genes. The current study was designed to evaluate the antidrug and virulence potential of A. hydrophila by amplifying its antimicrobial resistance and virulence genes using PCR and examining their effects on fish tissues and organs. A total of 960 fish samples of Channa marulius and Sperata sarwari were collected from four sites of the rivers of the Punjab, Pakistan. A. hydrophila isolates were subjected to biochemical identification and detection of virulence and antimicrobial resistance (AMR) genes by PCR. We retrieved 181 (6.46%) A. hydrophila isolates from C. marulius and 177 (6.25%) isolates from S. sarwari. Amplification through PCR revealed the incidence of virulence genes in 95.7% of isolates in C. marulius and 94.4% in S. sarwari. Similarly, amplification through PCR also revealed occurrence of AMR genes in 87.1% of isolates in C. marulius and 83.9% in S. sarwari. Histopathological examination revealed congestion (5.2%) and hepatocyte necrosis (4.6%) in liver, lamellar fusion (3.3%) and the presence of bacterial colonies (3.7%) in gills, fin erosion (6%), and the presence of biofilms (3.5%) in tail fins of infected fish. Phylogenetic tree analysis of 16S rRNA and gyrB gene of A. hydrophila revealed 100% and 97% similarity, respectively, with 16S rRNA gene and gyrB of A. hydrophila isolated in previous studies. The results of antimicrobial susceptibility testing showed that all isolates demonstrated resistance to sulfamethoxazole, ampicillin, neomycin, and norfloxacin, while susceptibility to gentamicin, chloramphenicol, and tetracycline, and intermediate resistance was observed against cefotaxime. The results concluded that examined fish samples were markedly contaminated with virulent and multidrug strains of A. hydrophila which may be of a potential health risk. The study emphasizes the responsible antimicrobial use in aquaculture and the urgent need for effective strategies to control the spread of virulence and antimicrobial resistance genes in A. hydrophila.
Topics: Animals; Aeromonas hydrophila; Phylogeny; Pakistan; RNA, Ribosomal, 16S; Anti-Bacterial Agents; Catfishes; Aeromonas; Gram-Negative Bacterial Infections
PubMed: 38551906
DOI: 10.1371/journal.pone.0297979 -
Frontiers in Immunology 2023The interactions between the host immune system and intestinal microorganisms have been studied in many animals, including fish. However, a detailed analysis has not...
The interactions between the host immune system and intestinal microorganisms have been studied in many animals, including fish. However, a detailed analysis has not been performed in medaka, an established fish model for biological studies. Here, we investigated the effect of immunodeficiency on the microbiota composition and the effect of gut bacteria on intestinal epithelial development and immune responses in medaka. Chronological analysis of the intestinal microbiota of mutant medaka showed a gradual decrease in the evenness of operational taxonomic units, mainly caused by the increased abundance of the Aeromonadaceae family. Exposure of wild-type medaka to high doses of an intestine-derived opportunistic bacterium of the Aeromonadaceae family induced an inflammatory response, suggesting a harmful effect on adult mutants. In addition, we established germ-free conditions in larval medaka and observed large absorptive vacuoles in intestinal epithelial cells, indicating a block in epithelial maturation. Transcriptome analysis revealed a decrease in the expression of genes involved in the defense response, including the antimicrobial peptide gene , whose expression is induced by lipopolysaccharide stimulation in normal larvae. These results show that reciprocal interactions between the microbiome and the intestinal tract are required for the maturation of the medaka immune system.
Topics: Animals; Oryzias; Microbiota; Gastrointestinal Microbiome; Growth and Development; Immune System
PubMed: 37767090
DOI: 10.3389/fimmu.2023.1259519 -
Pathogens (Basel, Switzerland) Sep 2023The genus belongs to the family. A patient with a pancreas-kidney transplant had multiple episodes of abdominal sepsis after surgery. was isolated in the ascitic and...
The genus belongs to the family. A patient with a pancreas-kidney transplant had multiple episodes of abdominal sepsis after surgery. was isolated in the ascitic and biliary fluid drains. After discharge, the patient had several diarrhea episodes, and was isolated in four stool samples. We decided to test whether the one strain that we initially isolated in ascitic fluid was the same that appeared in the successive stool samples. Five isolates of were found in the patient. Identification was performed using the MALDI-TOF system and confirmed via multiplex PCR. The analysis of the REP-PCR fingerprint patterns showed one cluster and confirmed that all isolates were related. We also demonstrated the virulent character of this species associated with genes encoding different toxins (act, alt, ast, hlyA, and aerA). The virulence of this species is associated with the expression of genes that encode different toxins, structural proteins, and metal-associated proteins. This case report highlights the severity of this disease, especially in immunocompromised patients, and its adequate treatment.
PubMed: 37764959
DOI: 10.3390/pathogens12091151 -
Microbiology Spectrum Dec 2023In this work, we demonstrate the epidemiologic relevance of the genus as the cause of infective diarrhea in North East Italy, both in children and adult subjects, with...
In this work, we demonstrate the epidemiologic relevance of the genus as the cause of infective diarrhea in North East Italy, both in children and adult subjects, with the significative presence of highly pathogenic strains. strains possess a heterogeneous armamentarium of pathogenicity factors that allows the microbe to affect a wide range of human intestinal epithelial cell processes that justify the ability to induce diarrhea through different mechanisms and cause diseases of variable severity, as observed for other gastrointestinal pathogens. However, it remains to be determined whether specific genotype(s) are associated with clinical pictures of different severity to implement the diagnostic and therapeutic approaches for this relevant enteric pathogen.
Topics: Child; Adult; Humans; Virulence; Aeromonas; Prevalence; Diarrhea; Italy
PubMed: 37855641
DOI: 10.1128/spectrum.00807-23 -
Virus Research Sep 2023Aeromonas salmonicida subsp. salmonicida is a Gam-negative bacterium responsible for furunculosis in fish. Because this aquatic bacterial pathogen has a rich reservoir...
Aeromonas salmonicida subsp. salmonicida is a Gam-negative bacterium responsible for furunculosis in fish. Because this aquatic bacterial pathogen has a rich reservoir of antibiotic-resistant genes, it is essential to investigate antibacterial alternatives, including the use of phages. Yet, we have previously demonstrated the inefficiency of a phage cocktail designed against A. salmonicida subsp. salmonicida strains due to a phage resistance phenotype associated to a prophage, namely Prophage 3. To bypass this resistance, one of the solutions is to isolate novel phages capable of infecting Prophage 3-bearing strains. Here we report on the isolation and characterization of the new virulent phage vB_AsaP_MQM1 (or MQM1), which is highly specific to A. salmonicida subsp. salmonicida strains. Phage MQM1 inhibited the growth of 01-B516, a strain carrying Prophage 3, including when combined to the previous phage cocktail. MQM1 infected 26 out of the 30 (87%) Prophage 3-bearing strains tested. Its linear dsDNA genome contains 63,343 bp, with a GC content of 50.2%. MQM1 genome can encode 88 proteins and 8 tRNAs, while no integrase or transposase-encoding genes were found. This podophage has an icosahedral capsid and a non-contractile short tail. We suggest that MQM1 may be a good addition to future phage cocktails against furunculosis to resolve the Prophage 3-resistance issue.
Topics: Animals; Bacteriophages; Furunculosis; Prophages; Aeromonas salmonicida; Fishes
PubMed: 37385348
DOI: 10.1016/j.virusres.2023.199165 -
Journal of Global Antimicrobial... Jun 2024Herein, we detected one multidrug-resistant Aeromonas hydrophila strain K522 co-carrying two bla genes together with a novel chromosomal integrative and mobilizable...
Coexistence of a novel chromosomal integrative and mobilizable element Tn7548 with two bla-carrying plasmids in a multidrug-resistant Aeromonas hydrophila strain K522 from China.
OBJECTIVES
Herein, we detected one multidrug-resistant Aeromonas hydrophila strain K522 co-carrying two bla genes together with a novel chromosomal integrative and mobilizable element (IME) Tn7548 from China. To reveal the genetic characteristics of the novel reservoir of bla and IME in Aeromonas, a detailed genomic characterization of K522 was performed, and a phylogenetic analysis of Tn7412-related IMEs was carried out.
METHODS
Carbapenemases were detected by using the immunocolloidal gold technique and antimicrobial susceptibility was tested by using VITEK 2. The whole-genome sequences of K522 were analysed using phylogenetics, detailed dissection, and comparison.
RESULTS
Strain K522 carried a Tn7412-related chromosomal IME Tn7548 and three resistance plasmids pK522-A-KPC, pK522-B-KPC, and pK522-MOX. A phylogenetic tree of 82 Tn7412-related IMEs was constructed, and five families of IMEs were divided. These IMEs shared four key backbone genes: int, repC, and hipAB, and carried various profiles of antimicrobial resistance genes (ARGs). pK522-A-KPC and pK522-B-KPC carried bla and belonged to IncG and unclassified type plasmid, respectively. The bla regions of these two plasmids were the truncated version derived from Tn6296, resulting in the carbapenem resistance of K522.
CONCLUSION
We first reported A. hydrophila harbouring a novel Tn7412-related IME Tn7548 together with two bla carrying plasmids and a MDR plasmid. Three of these four mobile genetic elements (MGEs) discovered in A. hydrophila K522 were novel. The emergence of novel MGEs carrying ARGs indicated the rapid evolution of the resistance gene vectors in A. hydrophila under selection pressure and would contribute to the further dissemination of various ARGs in Aeromonas.
Topics: Aeromonas hydrophila; Plasmids; Drug Resistance, Multiple, Bacterial; China; beta-Lactamases; Phylogeny; Humans; Bacterial Proteins; Microbial Sensitivity Tests; Anti-Bacterial Agents; Whole Genome Sequencing; Gram-Negative Bacterial Infections; DNA Transposable Elements; Chromosomes, Bacterial
PubMed: 38552873
DOI: 10.1016/j.jgar.2024.03.006 -
Applied and Environmental Microbiology Jul 2023Pellicles are biofilms that form at the air-liquid interface. We demonstrated that specific strains of Escherichia coli formed pellicles in single cultures when...
Socializing at the Air-Liquid Interface: a Functional Genomic Analysis on Biofilm-Related Genes during Pellicle Formation by Escherichia coli and Its Interaction with Aeromonas australiensis.
Pellicles are biofilms that form at the air-liquid interface. We demonstrated that specific strains of Escherichia coli formed pellicles in single cultures when cocultured with Carnobacterium maltaromaticum and E. coli O157:H7 but not with Aeromonas australiensis. Therefore, a combination of comparative genomic, mutational, and transcriptome analyses were applied to identify the unique genes in pellicle formation and investigate gene regulation under different growth phases. Here, we report that pellicle-forming strains do not harbor unique genes relative to non-pellicle-forming strains; however, the expression level of biofilm-related genes differed, especially for the genes encoding curli. Further, the regulatory region of curli biosynthesis is phylogenetically different among pellicle- and non-pellicle-forming strains. The disruption on modified cellulose and regulatory region of curli biosynthesis abolished pellicle formation in strains of E. coli. Besides, the addition of quorum sensing molecules (C-homoserine lactones [C-HSL]), synthesized by species, to pellicle formers abolished pellicle formation and implied a role of quorum sensing on pellicle formation. The deletion of autoinducer receptor in E. coli did not restore pellicle formation when cocultured with A. australiensis but modulated expression level of genes for curli and cellulose biosynthesis, resulting in a thinner layer of pellicle. Taken together, this study identified genetic determinants for pellicle formation and characterized the switching between pellicle to surface-associated biofilm in a dual-species environment, facilitating better understanding of the mechanisms for pellicle formation in E. coli and related organisms. To date, most attention has focused on biofilm formation on solid surfaces. By comparison, the knowledge on pellicle formation at the air-liquid interface is more limited and few studies document how bacteria decide on whether to form biofilms on solid surfaces or pellicles at the air-liquid interface to the surface-associated biofilms at the bottom. In this report, we characterized the regulation of biofilm-related genes during pellicle formation and document that interspecies communication via quorum sensing contributes to regulating the switch from pellicle to surface-associated biofilm. The discoveries expand the current view of regulatory cascades associated with pellicle formation.
Topics: Biofilms; Aeromonas; Escherichia coli O157; Genomics; Cellulose
PubMed: 37310210
DOI: 10.1128/aem.00456-23 -
Microbiology Spectrum Aug 2023species are emerging human enteric pathogens. However, they are currently not routinely detected in many diagnostic laboratories, and information regarding enteric...
species are emerging human enteric pathogens. However, they are currently not routinely detected in many diagnostic laboratories, and information regarding enteric infections detected using molecular methods is lacking. Here, we investigated the detection of species and four other enteric bacterial pathogens in 341,330 fecal samples from patients with gastroenteritis processed in a large Australian diagnostic laboratory between 2015 and 2019. These enteric pathogens were detected using quantitative real-time PCR (qPCR) methods. Furthermore, we compared the qPCR cycle threshold () values obtained from fecal samples that tested positive for only by molecular detection with those of samples that tested positive by both molecular detection and bacterial isolation methods. species were found to be the second most common bacterial enteric pathogens among patients with gastroenteritis. We observed a unique pattern of three infection peaks for , which correlated with the age of the patients. species were the most common enteric bacterial pathogens in children younger than 18 months. Fecal samples that tested positive for only by molecular detection had significantly higher values than fecal samples that tested positive by both molecular detection and bacterial culture. In conclusion, our findings reveal that enteric pathogens exhibit an age-related three-peak infection pattern, distinguishing them from other enteric bacterial pathogens. Moreover, the high rate of enteric infection discovered in this study suggests that species should be routinely tested in diagnostic laboratories. Our data also show that combining qPCR with bacterial culture can enhance the detection of enteric pathogens. species are emerging human enteric pathogens. However, these species are currently not routinely detected in many diagnostic laboratories, and no studies have reported the detection of enteric infection using molecular methods. We investigated the presence of species and four other enteric bacterial pathogens in 341,330 fecal samples from patients with gastroenteritis using quantitative real-time PCR (qPCR) methods. Interestingly, we discovered that species were the second most common bacterial enteric pathogens in patients with gastroenteritis, exhibiting a novel infection pattern compared to those of other enteric pathogens. Furthermore, we found that species were the most prevalent enteric bacterial pathogens in children aged 6 to 18 months. Our data also revealed that qPCR methods exhibit higher sensitivity in detecting enteric pathogens compared to that of bacterial culture alone. Moreover, combining qPCR with bacterial culture enhances the detection of enteric pathogens. These findings emphasize the importance of species in public health.
Topics: Child; Humans; Aeromonas; Australia; Gastroenteritis; Enterobacteriaceae Infections; Real-Time Polymerase Chain Reaction; Enterobacteriaceae; Feces
PubMed: 37378724
DOI: 10.1128/spectrum.00286-23 -
Journal of Global Antimicrobial... Dec 2023
Topics: Aeromonas caviae; beta-Lactamases; Aeromonas
PubMed: 37918788
DOI: 10.1016/j.jgar.2023.10.020