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Polish Journal of Veterinary Sciences Mar 2024Vibrio species are common inhabitants of aquatic environments and have been described in connection with fish and human diseases. Six Vibrio species were isolated from...
Vibrio species are common inhabitants of aquatic environments and have been described in connection with fish and human diseases. Six Vibrio species were isolated from diseased freshwater and ornamental fish in Poland. The strains were identified based on morphological and biochemical characteristics and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) as V. albensis (n=3) from Gymnocephalus cernua, Sander lucioperca, Paracheirodon innesi, and Xiphophorus hellerii; V. mimicus (n=1) from Xiphophorus maculatus; and V. vulnificus (n=1) from Nematobrycon palmeri. This is the first time that Vibrio species have been isolated and described from ornamental fish in Poland. The isolates were resistant to ampicillin (83.3%), gentamicin (16.6%), ciprofloxacin (16.6%), sulfamethoxazole-trimethoprim (16.6%), and chloramphenicol (16.6%). The multiple antibiotic resistance (MAR) index was 0.00-0.08 for V. albensis, 0.17 for V. mimicus, and 0.33 for V. vulnificus. Our study confirmed the presence of potentially pathogenic Vibrio species in freshwater and ornamental fish. Therefore, further monitoring of the presence of Vibrio species, mainly in ornamental fish, is necessary.
Topics: Humans; Animals; Poland; Vibrio Infections; Vibrio; Fishes; Fresh Water
PubMed: 38511636
DOI: 10.24425/pjvs.2024.149341 -
Frontiers in Microbiology 2024is a free-living marine bacterium associated with the contamination of fish and shellfish-the most consumed seafood in Asia. Owing to its potentially lethal clinical...
is a free-living marine bacterium associated with the contamination of fish and shellfish-the most consumed seafood in Asia. Owing to its potentially lethal clinical consequences, the consumption of seafood contaminated with has become a growing public health concern. This systematic review with meta-analysis and meta-regression aimed to integrate data on the prevalence of seafood-borne specifically in Asia and assess the potential risk factors that can influence the outcomes. A comprehensive literature search of four electronic databases yielded 279 relevant studies, among which 38 fulfilled the inclusion criteria. These selected studies were subjected to risk-of-bias assessment and data extraction by three independent researchers. A meta-analysis of the eligible studies estimated the overall prevalence of seafood-borne in Asia to be 10.47% [95% confidence interval (CI): 6.8-15.8%], with bivalve shellfish, such as oysters, mussels, clams, and cockles being the most contaminated seafood. The highest prevalence was reported in Japan, where 47.6% of the seafood samples tested positive for . The subgroup and meta-regression analyses identified three potential covariates-detection method, publication year, and country-associated with between-study heterogeneity. Furthermore, data visualization displayed the variations in prevalence across the studies, associated with differences in sample type, sample size, and sampling stage. This study provides valuable insights into the prevalence of in fish and shellfish across the entire Asian continent and highlights the potential factors that cause variation in the prevalence rates among the studies. These findings underscore the importance of enhancing hygiene measures throughout the seafood supply chain to mitigate infection risks and ensure the safety of consumers.
PubMed: 38511007
DOI: 10.3389/fmicb.2024.1363560 -
Natural Product Research Mar 2024The infection of is an important cause of huge economic losses in aquaculture industry. At present, antibiotics are mainly used to prevent and reduce the infection of...
The infection of is an important cause of huge economic losses in aquaculture industry. At present, antibiotics are mainly used to prevent and reduce the infection of the , which has accelerated the emergence of multi-drug-resistant strains. New generation alternative anti- drugs were in urgent to solve this problem. In this study, six compounds () were isolated from the sp. ZZ741A, a marine-derived variant, including one new compound, 2-carbamoylphenyl isobutyrate (), five known ones, nocardamine (), dehydroxynocardamine (), phenylacetic acid (), thiophenol () and 2,3-dihydroxybenzoic acid (). The antivibriosis assay showed that compounds and had specific inhibition activity against , , and with the MIC values ranging from 8 to 128 μg/mL. The molecular docking study of their possible mechanism of anti-vibriosis activity showed that the activity might come from the inhibition of Outer membrane protein U (OmpU).
PubMed: 38486398
DOI: 10.1080/14786419.2024.2321487 -
Journal of Infection and Chemotherapy :... Mar 2024Gallic acid (GA) has a good therapeutic effect in bacteriological inhibition and plays a variety of functions in maintaining the stability of the immune system. The aim...
INTRODUCTION
Gallic acid (GA) has a good therapeutic effect in bacteriological inhibition and plays a variety of functions in maintaining the stability of the immune system. The aim of the present study was to investigate the effect of GA on the bactericidal activity of macrophages against Vibrio vulnificus (Vv).
METHODS
A cell counting kit-8 (CCK-8) assay was carried out to test the cytotoxicity of GA on J774A.1 cells. Concentration of proinflammatory cytokines in J774A.1 cells were evaluated by ELISA. The internalization and degradation of Vv in the phagosomes were observed by transmission electron microscopy (TEM). The phagosome acidification and phagolysosome formation were detected to evaluate the bacteria-clearing function of J774A.1 cells. The bactericidal activity of GA in vivo was also investigated by collecting the survival time of Vv infected mice and observing the inflammatory infiltration of organs.
RESULTS
Our results demonstrated that GA at 50 μM significantly inhibited the proinflammatory cytokines levels, promoted phagosome acidification and phagolysosome formation in J774A.1 cells with Vv infection. This may be related to the activation of NLRP3/mTOR signaling pathway. Additionally, GA treatment improves the survival and bactericidal activity of mice infected with Vv.
CONCLUSIONS
In summary, GA exerts bactericidal activity against Vv infection by regulating the formation and acidification of phagocytic lysosomes in macrophages.
PubMed: 38462174
DOI: 10.1016/j.jiac.2024.02.030 -
International Journal of Food... May 2024Citral has attracted much attention as a safe and effective plant-derived bacteriostatic agent. However, the ability of citral to induce the formation of VBNC state in...
Citral has attracted much attention as a safe and effective plant-derived bacteriostatic agent. However, the ability of citral to induce the formation of VBNC state in Vibrio vulnificus has not been evaluated. In the present study, V. vulnificus was shown to be induced to form the VBNC state at 4.5 h and 3 h of citral treatment at 4MIC and 6MIC. Moreover, the citral-induced VBNC state of V. vulnificus maintained some respiratory chain activity and was able to recover well in both APW media, APW media supplemented with 5 % (v/v) Tween 80 and 2 mg/mL sodium pyruvate. Field emission and transmission electron microscopy showed that the external structure of the citral-induced VBNC V. vulnificus cells was shortened to short rods, with folded cell membrane, rough cell surface, and dense cytoplasm and loose nuclear material in the internal cell structure. In addition, the possible molecular mechanisms of citral-induced formation and recovery of V. vulnificus in the VBNC state were explored by transcriptomics. Transcriptome analyses revealed that 1118 genes were significantly altered upon entry into the VBNC state, and 1052 genes were changed after resuscitation. Most of the physiological activities related to energy production were inhibited in the citral-induced VBNC state of V. vulnificus; however, the bacteria retained its pathogenicity. The citral-induced resuscitation of V. vulnificus in the VBNC state selectively restored the activity of some genes related to bacterial growth and reproduction. Meanwhile, the expression levels of other genes may have been influenced by citral-induced resuscitation after the formation of the VBNC state. In conclusion, this study evaluated and analyzed the ability and possible mechanism of citral on the formation of VBNC state and the recovery of VBNC state of V. vulnificus, and made a comprehensive assessment for the safety of citral application in food production.
Topics: Vibrio vulnificus; Gene Expression Profiling; Acyclic Monoterpenes
PubMed: 38461733
DOI: 10.1016/j.ijfoodmicro.2024.110656 -
ACS Chemical Biology Mar 2024Translational riboswitches located in the 5' UTR of the messenger RNA (mRNA) regulate translation through variation of the accessibility of the ribosome binding site...
Translational riboswitches located in the 5' UTR of the messenger RNA (mRNA) regulate translation through variation of the accessibility of the ribosome binding site (RBS). These are the result of conformational changes in the riboswitch RNA governed by ligand binding. Here, we use a combination of single-molecule colocalization techniques (Single-Molecule Kinetic Analysis of RNA Transient Structure (SiM-KARTS) and Single-Molecule Kinetic Analysis of Ribosome Binding (SiM-KARB)) and microscale thermophoresis (MST) to investigate the adenine-sensing riboswitch in , focusing on the changes of accessibility between the ligand-free and ligand-bound states. We show that both methods faithfully report on the accessibility of the RBS within the riboswitch and that both methods identify an increase in accessibility upon adenine binding. Expanding on the regulatory context, we show the impact of the ribosomal protein S1 on the unwinding of the RNA secondary structure, thereby favoring ribosome binding even for the apo state. The determined rate constants suggest that binding of the ribosome is faster than the time required to change from the ON state to the OFF state, a prerequisite for efficient regulation decision.
Topics: Riboswitch; Adenine; Ligands; Kinetics; Ribosomes; Nucleic Acid Conformation
PubMed: 38412235
DOI: 10.1021/acschembio.3c00435 -
BioRxiv : the Preprint Server For... Feb 2024In species, quorum sensing signaling culminates in the production of a TetR-type master transcription factor collectively called the LuxR/HapR family, which regulates...
UNLABELLED
In species, quorum sensing signaling culminates in the production of a TetR-type master transcription factor collectively called the LuxR/HapR family, which regulates genes required for colonization and infection of host organisms. These proteins possess a solvent accessible putative ligand binding pocket. However, a native ligand has not been identified, and the role of ligand binding in LuxR/HapR function in is unknown. To probe the role of the ligand binding pocket, we utilize the small molecule thiophenesulfonamide inhibitor PTSP (3- henyl-1-( hiophen-2-yl ulfonyl)-1 - yrazole) that we previously showed targets LuxR/HapR proteins. Amino acid conservation in the ligand binding pocket determines the specificity and efficacy of PTSP inhibition across species. Here, we used structure-function analyses to identify PTSP-interacting residues in the ligand binding pocket of SmcR - the LuxR/HapR homolog - that are required for PTSP inhibition of SmcR activity . Forward genetic screening combined with X-ray crystallography structural determination of SmcR bound to PTSP identified substitutions at eight residues that were sufficient to reduce or eliminate PTSP-mediated SmcR inhibition. Small-angle X-ray scattering and computational modeling determined that PTSP drives allosteric unfolding at the N-terminal DNA binding domain. We discovered that SmcR is degraded by the ClpAP protease in the presence of PTSP ; substitution of key PTSP-interacting residues stabilized or increased SmcR levels in the cell. This mechanism of inhibition is observed for all thiophenesulfonamide compounds tested and against other species. We conclude that thiophenesulfonamides specifically bind in the ligand binding pocket of LuxR/HapR proteins, promoting protein degradation and thereby suppressing downstream gene expression, implicating ligand binding as a mediator of LuxR/HapR protein stability and function to govern virulence gene expression in pathogens.
SIGNIFICANCE
LuxR/HapR proteins were discovered in the 1990s as central regulators of quorum sensing gene expression and later discovered to be conserved in all studied species. LuxR/HapR homologs regulate a wide range of genes involved in pathogenesis, including but not limited to genes involved in biofilm production and toxin secretion. As archetypal members of the broad class of TetR-type transcription factors, each LuxR/HapR protein has a predicted ligand binding pocket. However, no ligand has been identified for LuxR/HapR proteins that control their function as regulators. Here, we used LuxR/HapR-specific chemical inhibitors to determine that ligand binding drives proteolytic degradation , the first demonstration of LuxR/HapR function connected to ligand binding for this historical protein family.
PubMed: 38405947
DOI: 10.1101/2024.02.15.580527 -
Microorganisms Feb 2024This study aimed to explore the phenotype and relationship of drug resistance genes in livestock and poultry farm wastewater and drinking water reservoirs to provide...
This study aimed to explore the phenotype and relationship of drug resistance genes in livestock and poultry farm wastewater and drinking water reservoirs to provide evidence for the transmission mechanisms of drug resistance genes, in order to reveal the spread of drug resistance genes in wastewater from intensive farms in Central China to urban reservoirs that serve as drinking water sources and provide preliminary data for the treatment of wastewater from animal farms to reduce the threat to human beings. DNA extraction and metagenomic sequencing were performed on eight groups of samples collected from four water reservoirs and four related wastewaters from animal farms in Central China. Metagenomic sequencing showed that the top 20 AROs with the highest abundance were _gene, _gene, , , , _gene_, _gene, , _gene, _gene, , , , , _gene, , _gene, , , and . The resistance genes mentioned above belong to the following categories of drug resistance mechanisms: antibiotic target replacement, antibiotic target protection, antibiotic inactivation, and antibiotic efflux. The resistomes that match the top 20 genes are and ; ; ; and . ; ; and ; and ; , , , , , , , , , and ; and ; , , , , , and ; and ; and ; , , and ; , , , , , , and . Unreported drug resistance genes and drug-resistant bacteria in Central China were identified in 2023. In the transmission path of drug resistance genes, the transmission path from aquaculture wastewater to human drinking water sources cannot be ignored. For the sake of human health and ecological balance, the treatment of aquaculture wastewater needs to be further strengthened, and the effective blocking of drug resistance gene transmission needs to be considered.
PubMed: 38399800
DOI: 10.3390/microorganisms12020396 -
Parasites & Vectors Feb 2024Traditional methods for detecting insect-borne bacterial pathogens are time-consuming and require specialized laboratory facilities, limiting their applicability in...
BACKGROUND
Traditional methods for detecting insect-borne bacterial pathogens are time-consuming and require specialized laboratory facilities, limiting their applicability in areas without access to such resources. Consequently, rapid and efficient detection methods for insect-borne bacterial diseases have become a pressing need in disease prevention and control.
METHODS
We aligned the ribosomal 16S rRNA sequences of seven bacterial species (Staphylococcus aureus, Shigella flexneri, Aeromonas caviae, Vibrio vulnificus, Salmonella enterica, Proteus vulgaris, and Yersinia enterocolitica) by DNASTAR Lasergene software. Using DNASTAR Lasergene and Primer Premier software, we designed universal primers RLB-F and RLB-R, two species-specific probes for each pathogen, and a universal probe (catch-all). The PCR products of seven standard strains were hybridized with specific oligonucleotide probes fixed on the membrane for specific experimental procedures. To evaluate the sensitivity of PCR-RLB, genomic DNA was serially diluted from an initial copy number of 10 to 10 copies/μl in distilled water. These dilutions were utilized as templates for the PCR-RLB sensitivity analysis. Simultaneous detection of seven fly-borne bacterial pathogens from field samples by the established PCR-RLB method was conducted on a total of 1060 houseflies, collected from various environments in Lanzhou, China.
RESULTS
The established PCR-RLB assay is capable of detecting bacterial strains of about 10 copies/μl for S. aureus, 10 copies/μl for S. flexneri, 10 copies/μl for A. caviae, 10 copies/μl for V. vulnificus, 10 copies/μl for S. enterica, 10 copies/μl for P. vulgaris, and 10 copies/μl for Y. enterocolitica. The results demonstrate that the detection rate of the established PCR-RLB method is higher (approximately 100 times) compared to conventional PCR. This method was applied to assess the bacterial carrier status of flies in various environments in Lanzhou, China. Among the seven bacterial pathogens carried by flies, S. enterica (34.57%), S. flexneri (32.1%), and Y. enterocolitica (20.37%) were found to be the predominant species.
CONCLUSIONS
Overall, this research shows that the rapid and efficient PCR-RLB detection technology could be a useful for surveillance and therefore effective prevention and control the spread of insect-borne diseases. Meanwhile, the experimental results indicate that urban sanitation and vector transmission sources are important influencing factors for pathogen transmission.
Topics: Animals; Bacteria; Diptera; Nucleic Acid Hybridization; RNA, Ribosomal, 16S; Sensitivity and Specificity; Staphylococcus aureus
PubMed: 38389104
DOI: 10.1186/s13071-024-06170-3 -
International Journal of Infectious... Apr 2024South Asia remains home to foodborne diseases caused by the Vibrio species. We aimed to compile and update information on the epidemiology of vibriosis in South Asia. (Meta-Analysis)
Meta-Analysis
OBJECTIVES
South Asia remains home to foodborne diseases caused by the Vibrio species. We aimed to compile and update information on the epidemiology of vibriosis in South Asia.
METHODS
For this systematic review and meta-analysis, we searched PubMed, Web of Science, EMBASE, and Google Scholar for studies related to vibriosis in South Asia published up to May 2023. A random-effects meta-analysis was used to estimate the pooled isolation rate of non-cholera-causing Vibrio species.
RESULTS
In total, 38 studies were included. Seven of these were case reports and 22 were included in the meta-analysis. The reported vibriosis cases were caused by non-O1/non-O139 V. cholerae, V. parahaemolyticus, V. fluvialis, and V. vulnificus. The overall pooled isolation rate was 4.0% (95% confidence interval [CI] 3.0-5.0%) in patients with diarrhea. Heterogeneity was high (I = 98.0%). The isolation rate of non-O1/non-O139 V. cholerae, V. parahaemolyticus, and V. fluvialis were 9.0 (95% CI 7.0-10.0%), 1.0 (95% CI 1.0-2.0%), and 2.0 (95% CI: 1.0-3.0%), respectively. Regarding V. parahaemolyticus, O3:K6 was the most frequently isolated serotype. Cases peaked during summer. Several studies reported antibiotic-resistant strains and those harboring extended-spectrum beta-lactamases genes.
CONCLUSIONS
This study demonstrates a high burden of infections caused by non-cholera-causing Vibrio species in South Asia.
Topics: Humans; Vibrio cholerae; Vibrio Infections; Foodborne Diseases; Diarrhea; Asia, Southern
PubMed: 38311027
DOI: 10.1016/j.ijid.2024.01.022