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Asian Pacific Journal of Tropical... Nov 2015To investigate the in vitro antimicrobial potential of extracts of stem, leaves, flowers, pods and seeds of Moringa oleifera (M. oleifera) against Vibrio spp. from...
OBJECTIVE
To investigate the in vitro antimicrobial potential of extracts of stem, leaves, flowers, pods and seeds of Moringa oleifera (M. oleifera) against Vibrio spp. from hatchery water and the prawn Macrobrachium amazonicum.
METHODS
The ethanol extracts of stem, leaves, pods and seeds and chloroform extract of flowers of M. oleifera were tested against Vibrio cholerae (V. cholerae) serogroups non-O1/non-O139 (n = 4), Vibrio vulnificus (n = 1) and Vibrio mimicus (n = 1). Escherichia coli (E. coli) (ATCC(®) 25922) was used as quality control. Vibrio species were obtained from Macrobrachium amazonicum prawns and from hatchery water from prawn farming. The Minimum Inhibitory Concentration (MIC) was determined by broth microdilution method.
RESULTS
The best result was obtained with the ethanol extract of pods, which inhibited three strains of the V. cholerae, Vibrio vulnificus, Vibrio mimicus and E. coli (MIC range 0.312-5.000 mg/mL). The chloroform extract of flowers was effective against all V. cholerae strains and E. coli (MIC range 0.625-1.250 mg/mL). However, the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial growth.
CONCLUSIONS
The extracts of pods, flowers and leaves of M. oleifera have potential for the control of Vibrio spp. Further studies are necessary to isolate the bioactive compounds responsible for this antimicrobial activity.
PubMed: 26614991
DOI: 10.1016/j.apjtm.2015.10.012 -
Scientific Reports Nov 2019A potential mechanism for the global distribution of waterborne pathogens is through carriage by the migratory waterbirds. However, this mode of transmission has yet...
A potential mechanism for the global distribution of waterborne pathogens is through carriage by the migratory waterbirds. However, this mode of transmission has yet been confirmed epidemiologically. Here, we conducted whole genome sequencing of Vibrio spp. collected from waterbirds, sediments, and mollusks in the estuary of the Liaohe River in China to investigate this transmission mode. We found that a V. parahaemolyticus strain isolated from a waterbird was clonally related to the other V. parahaemolyticus strains obtained from the sediments and mollusks, and three V. mimicus strains isolated from bird feces were genomically related to those found in the mollusks and upstream groundwater, suggesting that the bird-carried Vibrio strains were acquired through the direct predation of the local mollusks. Surprisingly, two bird-carried V. parahaemolyticus strains belonging to the same clone were identified in Panjin and Shanghai, which are over 1,150 km apart, and another two were found at two locations 50 km apart, further supporting that waterbirds are capable of carrying and disseminating these pathogens over long distances. Our results provide the first evidence of direct transmission from mollusks to waterbirds and confirm that waterbirds act as disseminating vehicles of waterborne pathogens. Effective surveillance of migratory waterbirds along their routes will be valuable for predicting future epidemics of infectious diseases.
Topics: Animal Migration; Animals; Birds; Fisheries; Food Contamination; Genome, Bacterial; Genomics; Geography; Phylogeny; Phylogeography; Public Health Surveillance; Rivers; Vibrio; Vibrio Infections
PubMed: 31704994
DOI: 10.1038/s41598-019-52791-5 -
PloS One 2015Vibrio mimicus (V.mimicus) is a causative agent of ascites disease in aquatic animals. Our previous studies have demonstrated that the outer membrane protein U (OmpU)...
Vibrio mimicus (V.mimicus) is a causative agent of ascites disease in aquatic animals. Our previous studies have demonstrated that the outer membrane protein U (OmpU) from V.mimicus is an immunoprotective antigen with six immunodominant linear B-cell epitopes. Although the N-terminus of OmpU contains potential binding motifs, it remained unclear whether OmpU possesses adhesion function. Here, the adhesive capacity of recombinant OmpU and V.mimicus to epithelioma papulosum cyprinid (EPC) cells was determined by immunofluorescence and adherence assay. The results showed that after co-incubated with rOmpU, an obvious visible green fluorescence could be observed on the EPC cell surface and the nuclei exhibited blue fluorescence; while the control cell surface did not show any signal, only nuclei exhibited blue fluorescence. The average number of wild-type strain adhered to each cell was 32.3 ± 4.5. The average adhesion number of OmpU gene deletion mutant was significantly reduced to 10.8 ± 0.5 (P < 0.01) and restored to 31.3 ± 2.8 by complement strain (P >0.05). Pretreatment of cells with rOmpU reduced the average adhesion number of wild-type strain to 9.7 ± 2.9 (P < 0.01). Likewise, binding was significantly decreased to 8.8 ± 3.2 (P < 0.01) due to blocking role of OmpU antibodies. To determine binding motifs of OmpU, six immunodominant B-cell epitope peptides labeled with FITC were employed in flow cytometry-based binding assay. Two FITC-labeled epitope peptides (aa90-101 and aa173-192) showed strong binding to EPC cells (the fluorescence positive cell rate was 99 ± 0.6% and 98 ± 0.3%, respectively), which could be specifically competed by excess corresponding unlabeled peptides, whereas the remaining four showed a low level of background binding. This is the first demonstration that OmpU possesses adhesion function and its N terminal 90-101 and 173-192 amino acid regions are critical sites for cell surface binding.
Topics: Adhesins, Bacterial; Animals; Antibodies, Bacterial; Antigens, Bacterial; Bacterial Adhesion; Binding Sites; Cell Line; Epitopes, B-Lymphocyte; Fishes; Vibrio mimicus
PubMed: 25742659
DOI: 10.1371/journal.pone.0119026 -
Virulence Aug 2017
Topics: Animals; Bacterial Vaccines; Catfishes; Fish Diseases; Sequence Analysis, DNA; Vibrio Infections; Vibrio cholerae; Vibrio mimicus; Virulence; Whole Genome Sequencing
PubMed: 27763808
DOI: 10.1080/21505594.2016.1250996 -
Frontiers in Microbiology 2023HtpG, a bacterial homolog of the eukaryotic 90 kDa heat-shock protein (Hsp90), represents the simplest member of the heat shock protein family. While the significance of...
HtpG, a bacterial homolog of the eukaryotic 90 kDa heat-shock protein (Hsp90), represents the simplest member of the heat shock protein family. While the significance of Hsp90 in fungal and cancer drug resistance has been confirmed, the role of HtpG in bacterial antibiotic resistance remains largely unexplored. This research aims to investigate the impact of the gene on antibiotic resistance in . Through the creation of gene deletion and complementation strains, we have uncovered the essential role of in regulating the structural integrity of the bacterial cell envelope. Our transcriptomics analysis demonstrates that the deletion of increases the sensitivity of to antimicrobial peptides, primarily due to upregulated lipopolysaccharide synthesis, reduced glycerophospholipid content, and weakened efflux pumps activity. Conversely, reduced sensitivity to β-lactam antibiotics in the Δ strain results from decreased peptidoglycan synthesis and dysregulated peptidoglycan recycling and regulation. Further exploration of specific pathway components is essential for a comprehensive understanding of -mediated resistance mechanisms, aiding in the development of antimicrobial agents. To our knowledge, this is the first effort to explore the relationship between and drug resistance in bacteria.
PubMed: 38239724
DOI: 10.3389/fmicb.2023.1295065 -
PloS One 2015Diarrheal disease remains an unsolved problem in developing countries. The emergence of new etiological agents (non-cholera vibrios) is a major cause of concern for...
Diarrheal disease remains an unsolved problem in developing countries. The emergence of new etiological agents (non-cholera vibrios) is a major cause of concern for health planners. We attempted to unveil the seasonal dynamics of entero-pathogenic Vibrios in Gangetic riverine-estuarine ecosystem. 120 surface water samples were collected for a period of one year from 3 sampling sites on the Hooghly river. Five enteropathogenic Vibrio species, V. cholerae (35%), V. parahaemolyticus (22.5%), V. mimicus (19.1%), V. alginolyticus (15.8%) and V. vulnificus (11.6%), were present in the water samples. The vibriophages, V. vulnificus ɸ (17.5%), V. alginolyticus ɸ (17.5%), V. parahaemolyticus ɸ (10%), V. cholerae non-O1/O139 ɸ (26.6%) and V. mimicus ɸ (9.1%), were also detected in these samples. The highest number of Vibrios were noted in the monsoon (20-34°C), and to a lesser extent, in the summer (24-36°C) seasons. Samples positive for phages for any of the identified Vibrio species were mostly devoid of that particular bacterial organism and vice versa. The detection of toxin genes and resistance to β-lactam antibiotics in some environmental enteropathogenic Vibrio species in the aquatic niches is a significant outcome. This finding is instrumental in the south Bengal diarrhoeal incidence.
Topics: Bacterial Toxins; Bacteriophages; Cholera; Diarrhea; Ecosystem; Epidemiological Monitoring; Estuaries; Genes, Bacterial; Humans; India; Prevalence; Rivers; Seasons; Vibrio; Vibrio cholerae; Water Microbiology
PubMed: 26340543
DOI: 10.1371/journal.pone.0137338 -
Microbiology and Immunology Sep 2014Vibrio mimicus, a human pathogen that causes gastroenteritis, produces an enterotoxic hemolysin as a virulence factor. The hemolysin is secreted extracellularly as an...
Vibrio mimicus, a human pathogen that causes gastroenteritis, produces an enterotoxic hemolysin as a virulence factor. The hemolysin is secreted extracellularly as an inactive protoxin and converted to a mature toxin through removal of the N-terminal propeptide, which comprises 151 amino acid residues. In this study, a novel protease having the trypsin-like substrate specificity was purified from the bacterial culture supernatant. The N-terminal amino acid sequence of the purified protein was identical with putative trypsin VMD27150 of V. mimicus strain VM573. The purified protease was found to cause maturation of the protoxin by cleavage of the Arg(151)-Ser(152) bond. Deletion of the protease gene resulted in increased amounts of the protoxin in the culture supernatant. In addition, expression of the hemolysin and protease genes was detected during the logarithmic growth phase. These findings indicate that the protease purified may mediate maturation of the hemolysin.
Topics: Bacterial Proteins; Gene Deletion; Hemolysin Proteins; Peptide Hydrolases; Protein Processing, Post-Translational; Proteolysis; Sequence Analysis, Protein; Vibrio mimicus; Virulence Factors
PubMed: 25040152
DOI: 10.1111/1348-0421.12177 -
PloS One 2016Vibrio mimicus is a pathogen that causes ascites disease in fish. We have previously demonstrated that the outer membrane protein U (OmpU) is an important adhesin in V....
Vibrio mimicus is a pathogen that causes ascites disease in fish. We have previously demonstrated that the outer membrane protein U (OmpU) is an important adhesin in V. mimicus. Here eight specific OmpU-binding phage clones, which presented three different OmpU-binding peptides (designated P1, P2, P3), were screened from a commercially available phage displayed 12-mer peptide library using rOmpU protein as target. Then, synthetic OmpU-binding peptides were measured for their adhesion antagonistic activity and binding affinity via adhesion inhibition test and non-competitive ELISA, respectively. The results showed that after co-incubated with the mixture of rOmpU and P3, visible green fluorescence could be observed on the epithelioma papulosum cyprinidi (EPC) cells surface; while the EPC cells co-incubated with the mixture of rOmpU and P1/P2 exhibited little green fluorescence. The average adhesion number of V. mimicus 04-14 isolate before and after treatment with peptide was 21.4 ± 1.5, 20.8 ± 0.8 (irrelevant peptide), 20.2 ± 0.5 (P3), 5.1 ± 0.7 (P1) and 3.4 ± 0.8 (P2), respectively. There was a significant decrease in the adhesive level of 04-14 isolate treated with P1/ P2 compared to the untreated isolate (p<0.01). The affinity constants of P1 and P2 were (6.17 ± 0.19) × 108 L/mol and (1.24 ± 0.56) × 109 L/mol, respectively. Furthermore, protective effects of P1 and P2 on grass carps challenged with V. mimicus were preliminary detected. It was found there was delayed death of fish in the groups treated with P1/P2, and the survival rate of challenged fish improved with the increase of the dose of adhesion antagonistic peptide. Taken together, two novel OmpU-binding peptides, which possessed adhesion antagonistic activity, high affinity and a certain degree of antibacterial activity against V. mimicus, were screened and identified.
Topics: Adhesins, Bacterial; Animals; Anti-Bacterial Agents; Bacterial Adhesion; Carps; Cell Line; Fish Diseases; Fishes; Peptide Library; Peptides; Vibrio mimicus
PubMed: 27832083
DOI: 10.1371/journal.pone.0165092 -
PloS One 2015Despite that Vibrio spp. have a significant impact on the health of humans and aquatic animals, the molecular basis of their pathogenesis is little known, mainly due to...
Developing Universal Genetic Tools for Rapid and Efficient Deletion Mutation in Vibrio Species Based on Suicide T-Vectors Carrying a Novel Counterselectable Marker, vmi480.
Despite that Vibrio spp. have a significant impact on the health of humans and aquatic animals, the molecular basis of their pathogenesis is little known, mainly due to the limited genetic tools for the functional research of genes in Vibrio. In some cases, deletion of target DNAs in Vibrio can be achieved through the use of suicide vectors. However, these strategies are time-consuming and lack universality, and the widely used counterselectable gene sacB does not work well in Vibrio cells. In this study, we developed universal genetic tools for rapid and efficient deletion mutations in Vibrio species based on suicide T-Vectors carrying a novel counterselectable marker, vmi480. We explored two uncharacterized genes, vmi480 and vmi470, in a genomic island from Vibrio mimicus VM573 and confirmed that vmi480 and vmi470 constitute a two-component toxin-antitoxin system through deletion and expression of vmi480 and vmi470. The product of vmi480 exhibited strong toxicity to Escherichia coli cells. Based on vmi480 and the PBAD or PTAC promoter system, we constructed two suicide T-vectors, pLP11 and pLP12, and each of these vectors contained a multiple cloning region with two AhdI sites. Both vectors linearized by AhdI digestion could be stored and directly ligated with purified PCR products without a digestion step. By using pLP11 and pLP12 coupled with a highly efficient conjugation system provided by E. coli β2163, six genes from four representative Vibrio species were easily deleted. By using the counterselective marker vmi480, we obtained 3-12 positive colonies (deletion mutants) among no more than 20 colonies randomly selected on counterselection plates. The strategy does not require the digestion of PCR products and suicide vectors every time, and it avoids large-scale screening colonies on counterselective plates. These results demonstrate that we successfully developed universal genetic tools for rapid and efficient gene deletion in Vibrio species.
Topics: Bacterial Toxins; Escherichia coli; Genetic Vectors; Humans; Plasmids; Sequence Deletion; Vibrio
PubMed: 26641275
DOI: 10.1371/journal.pone.0144465 -
PloS One 2015The Vibrio cholerae N-acetyl glucosamine-binding protein A (GbpA) is a chitin-binding protein involved in V. cholerae attachment to environmental chitin surfaces and...
gbpA as a Novel qPCR Target for the Species-Specific Detection of Vibrio cholerae O1, O139, Non-O1/Non-O139 in Environmental, Stool, and Historical Continuous Plankton Recorder Samples.
The Vibrio cholerae N-acetyl glucosamine-binding protein A (GbpA) is a chitin-binding protein involved in V. cholerae attachment to environmental chitin surfaces and human intestinal cells. We previously investigated the distribution and genetic variations of gbpA in a large collection of V. cholerae strains and found that the gene is consistently present and highly conserved in this species. Primers and probe were designed from the gbpA sequence of V. cholerae and a new Taq-based qPCR protocol was developed for diagnostic detection and quantification of the bacterium in environmental and stool samples. In addition, the positions of primers targeting the gbpA gene region were selected to obtain a short amplified fragment of 206 bp and the protocol was optimized for the analysis of formalin-fixed samples, such as historical Continuous Plankton Recorder (CPR) samples. Overall, the method is sensitive (50 gene copies), highly specific for V. cholerae and failed to amplify strains of the closely-related species Vibrio mimicus. The sensitivity of the assay applied to environmental and stool samples spiked with V. cholerae ATCC 39315 was comparable to that of pure cultures and was of 102 genomic units/l for drinking and seawater samples, 101 genomic units/g for sediment and 102 genomic units/g for bivalve and stool samples. The method also performs well when tested on artificially formalin-fixed and degraded genomic samples and was able to amplify V. cholerae DNA in historical CPR samples, the earliest of which date back to August 1966. The detection of V. cholerae in CPR samples collected in cholera endemic areas such as the Benguela Current Large Marine Ecosystem (BCLME) is of particular significance and represents a proof of concept for the possible use of the CPR technology and the developed qPCR assay in cholera studies.
Topics: Feces; Genes, Bacterial; Humans; Microbiota; Molecular Typing; Plankton; Polymerase Chain Reaction; Seawater; Sensitivity and Specificity; Vibrio cholerae
PubMed: 25915771
DOI: 10.1371/journal.pone.0123983