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Journal of Visualized Experiments : JoVE May 2024Bacteria detect local population numbers using quorum sensing, a method of cell-cell communication broadly utilized to control bacterial behaviors. In Vibrio species,...
Bacteria detect local population numbers using quorum sensing, a method of cell-cell communication broadly utilized to control bacterial behaviors. In Vibrio species, the master quorum sensing regulators LuxR/HapR control hundreds of quorum sensing genes, many of which influence virulence, metabolism, motility, and more. Thiophenesulfonamides are potent inhibitors of LuxR/HapR that bind the ligand pocket in these transcription factors and block downstream quorum sensing gene expression. This class of compounds served as the basis for the development of a set of simple, robust, and educational procedures for college students to assimilate their chemistry and biology skills using a CURE model: course-based undergraduate research experience. Optimized protocols are described that comprise three learning stages in an iterative and multi-disciplinary platform to engage students in a year-long CURE: (1) design and synthesize new small molecule inhibitors based on the thiophenesulfonamide core, (2) use structural modeling to predict binding affinity to the target, and (3) assay the compounds for efficacy in microbiological assays against specific Vibrio LuxR/HapR proteins. The described reporter assay performed in E. coli successfully predicts the efficacy of the compounds against target proteins in the native Vibrio species.
Topics: Quorum Sensing; Vibrio; Trans-Activators; Repressor Proteins; Sulfonamides; Thiophenes; Anti-Bacterial Agents; Bacterial Proteins
PubMed: 38884467
DOI: 10.3791/66582 -
Applied and Environmental Microbiology Jun 2024Marine bacteria experience fluctuations in osmolarity that they must adapt to, and most bacteria respond to high osmolarity by accumulating compatible solutes also known...
Marine bacteria experience fluctuations in osmolarity that they must adapt to, and most bacteria respond to high osmolarity by accumulating compatible solutes also known as osmolytes. The osmotic stress response and compatible solutes used by the coral and oyster pathogen were unknown. In this study, we showed that to alleviate osmotic stress biosynthesized glycine betaine (GB) and transported into the cell choline, GB, ectoine, dimethylglycine, and dimethylsulfoniopropionate, but not -inositol. -inositol is a stress protectant and a signaling molecule that is biosynthesized and used by algae. Bioinformatics identified -inositol () catabolism clusters in and other , , , and species. Growth pattern analysis demonstrated that utilized -inositol as a sole carbon source, with a short lag time of 3 h. An deletion mutant, which encodes an inositol dehydrogenase, was unable to grow on -inositol. Within the clusters were an MFS-type () and an ABC-type () transporter and analyses showed that both transported -inositol. IolG and IolA phylogeny among species showed different evolutionary histories indicating multiple acquisition events. Outside of , IolG was most closely related to IolG from a small group of fish and human pathogens and species. However, IolG from hypervirulent strains clustered with IolG from and divergently from , , and plant pathogens. The cluster was also present within , , , , , , , , , and , of which many species were associated with marine flora and fauna.IMPORTANCEHost associated bacteria such as encounter competition for nutrients and have evolved metabolic strategies to better compete for food. Emerging studies show that -inositol is exchanged in the coral-algae symbiosis, is likely involved in signaling, but is also an osmolyte in algae. The bacterial consumption of -inositol could contribute to a breakdown of the coral-algae symbiosis during thermal stress or disrupt the coral microbiome. Phylogenetic analyses showed that the evolutionary history of -inositol metabolism is complex, acquired multiple times in , but acquired once in many bacterial plant pathogens. Further analysis also showed that a conserved cluster is prevalent among many marine species (commensals, mutualists, and pathogens) associated with marine flora and fauna, algae, sponges, corals, molluscs, crustaceans, and fish.
PubMed: 38874337
DOI: 10.1128/aem.00920-24 -
Journal of Agricultural and Food... Jun 2024Thymol has efficient bactericidal activity against a variety of pathogenic bacteria, but the bactericidal mechanism against () has rarely been reported. In the current...
Thymol has efficient bactericidal activity against a variety of pathogenic bacteria, but the bactericidal mechanism against () has rarely been reported. In the current study, we investigated the bactericidal mechanism of thymol against . The Results revealed that 150 μg/mL of thymol had 99.9% bactericidal activity on . Intracellular bursts of reactive oxygen species (ROS), Feaccumulation, lipid peroxidation, and DNA breakage were checked by cell staining. The exogenous addition of HO and catalase promoted and alleviated thymol-induced cell death to a certain extent, respectively, and the addition of the ferroptosis inhibitor Liproxstatin-1 also alleviated thymol-induced cell death, confirming that thymol induced Fenton-reaction-dependent ferroptosis in . Proteomic analysis revealed that relevant proteins involved in ROS production, lipid peroxidation accumulation, and DNA repair were significantly upregulated after thymol treatment. Molecular docking revealed two potential binding sites (amino acids 46H and 42F) between thymol and ferritin, and thymol could promote the release of Fe from ferritin proteins through in vitro interactions analyzed. Therefore, we hypothesized that ferritin as a potential target may mediate thymol-induced ferroptosis in . This study provides new ideas for the development of natural inhibitors for controlling in aquatic products.
Topics: Ferroptosis; Thymol; Reactive Oxygen Species; Vibrio parahaemolyticus; Hydrogen Peroxide; Anti-Bacterial Agents; Lipid Peroxidation; Iron; Molecular Docking Simulation; Ferritins; Bacterial Proteins
PubMed: 38867141
DOI: 10.1021/acs.jafc.4c01584 -
Proceedings of the National Academy of... Jun 2024causes life-threatening wound and gastrointestinal infections, mediated primarily by the production of a Multifunctional-Autoprocessing Repeats-In-Toxin (MARTX) toxin....
causes life-threatening wound and gastrointestinal infections, mediated primarily by the production of a Multifunctional-Autoprocessing Repeats-In-Toxin (MARTX) toxin. The most commonly present MARTX effector domain, the Makes Caterpillars Floppy-like (MCF) toxin, is a cysteine protease stimulated by host adenosine diphosphate (ADP) ribosylation factors (ARFs) to autoprocess. Here, we show processed MCF then binds and cleaves host s-related proteins in rain (Rab) guanosine triphosphatases within their C-terminal tails resulting in Rab degradation. We demonstrate MCF binds Rabs at the same interface occupied by ARFs. Moreover, we show MCF preferentially binds to ARF1 prior to autoprocessing and is active to cleave Rabs only subsequent to autoprocessing. We then use structure prediction algorithms to demonstrate that structural composition, rather than sequence, determines Rab target specificity. We further determine a crystal structure of aMCF as a swapped dimer, revealing an alternative conformation we suggest represents the open, activated state of MCF with reorganized active site residues. The cleavage of Rabs results in Rab1B dispersal within cells and loss of Rab1B density in the intestinal tissue of infected mice. Collectively, our work describes an extracellular bacterial mechanism whereby MCF is activated by ARFs and subsequently induces the degradation of another small host guanosine triphosphatase (GTPase), Rabs, to drive organelle damage, cell death, and promote pathogenesis of these rapidly fatal infections.
Topics: Animals; Female; Humans; Mice; ADP-Ribosylation Factors; Bacterial Toxins; HEK293 Cells; Mice, Inbred ICR; Proteolysis; rab GTP-Binding Proteins; Vibrio Infections; Vibrio vulnificus
PubMed: 38861595
DOI: 10.1073/pnas.2316143121 -
The Science of the Total Environment Sep 2024The final point-of-drinking water (FPODW) exposure to Vibrio and waterborne pathogens remains a misaim surveillance target. Therefore, the current study purposed to... (Meta-Analysis)
Meta-Analysis
Global and regional final point-of-drinking water prevalence of Vibrio pathogens: a systematic analysis with socioeconomic, global health security, and WASH indices-guided meta-regressions.
The final point-of-drinking water (FPODW) exposure to Vibrio and waterborne pathogens remains a misaim surveillance target. Therefore, the current study purposed to estimate the global and regional prevalence of Vibrio pathogens in FPODW. Vibrio-FPODW data derived from integrated databases per PRISMA protocol were fitted to a random-intercept-logistic mixed-effects and meta-regression models. The global FPODW Vibrio prevalence was 5.13% (95%CI: 2.24-11.30) with 7.76% (6.84-8.78) cross-validated value. Vibrio prevalence in different FPODW varied with the highest in unclassified (13.98%, 3.98-38.95), household stored (6.42%, 1.16-28.69), municipal (4.39%, 1.54-11.90), and bottled (1.06%, 0.00-98.57) FPODW. Regionally, FPODW Vibrio prevalence varied significantly with highest in Africa (6.31%, 0.49-47.88), then Asia (4.83%, 2.01-11.18). Similarly, it varied significantly among income classification with the highest from low-income (8.77%, 0.91-50.05), then lower-middle-income (6.16%, 2.75-13.20), upper-middle-income (0.23%, 0.00-82.04), and 0.94% (0.19-2.72) in high-income economies. Among the WHO region, it varied significantly from 1.41% (0.17-10.45) in Eastern Mediterranean, 6.31% (0.49-47.88) in Africa to 8.86% (3.85-19.06) in South-East Asia and declining among SDI-quintiles from 11.64% (3.29-33.83) in Low-SDI, 10.59% (4.58-22.61) in High-middle-SDI to 0.26% (0.01-9.09) in Middle-SDI. FPODW Vibrio prevalence was 7.31% (2.94-17.03) in the low-GHSIG, followed by 4.55% (0.00-100.00) in the upper-GHSIG, and 2.21% (0.31-14.24) in middle-GHSIG; rural (4.18%, 0.06-76.17) and urban (5.28%, 2.35-11.44) settings. Also, sample size, SDI, SDI-quintiles, and nation significantly explained 14.12%, 10.91%, 30.35%, and 87.65% variance in FPODW Vibrio prevalence, respectively as a univariate influence. Additionally, 11.90% variance in FPODW Vibrio prevalence explained mortality rate attributed to unsafe WASH services. In conclusion, the study revealed a substantial high FPODW prevalence of Vibrio calling for initiative-taking and intentional surveillances of waterborne pathogens at the neglected stage across nations in order to achieve sustainably the SDG 3.
Topics: Vibrio; Drinking Water; Prevalence; Water Microbiology; Global Health; Humans; Socioeconomic Factors
PubMed: 38852862
DOI: 10.1016/j.scitotenv.2024.173818 -
Current Biology : CB Jun 2024Strain-specific pili enable Vibrio cholerae bacteria to adhere to each other and form aggregates in liquid culture. A new study focuses on strains with less specific,...
Strain-specific pili enable Vibrio cholerae bacteria to adhere to each other and form aggregates in liquid culture. A new study focuses on strains with less specific, promiscuous pili and suggests a role for contact-dependent bacterial killing in shaping the composition of these aggregates.
Topics: Vibrio cholerae; Fimbriae, Bacterial; Bacterial Adhesion
PubMed: 38834027
DOI: 10.1016/j.cub.2024.04.042 -
Molecular Biology Reports Jun 2024Cystatin is a protease inhibitor that also regulates genes expression linked to inflammation and plays a role in defense and regulation.
BACKGROUND
Cystatin is a protease inhibitor that also regulates genes expression linked to inflammation and plays a role in defense and regulation.
METHODS AND RESULTS
Cystatin 10 (Smcys10) was cloned from Scophthalmus maximus and encodes a 145 amino acid polypeptide. The results of qRT-PCR showed that Smcys10 exhibited tissue-specific expression patterns, and its expression was significantly higher in the skin than in other tissues. The expression level of Smcys10 was significantly different in the skin, gill, head kidney, spleen and macrophages after Vibrio anguillarum infection, indicating that Smcys10 may play an important role in resistance to V. anguillarum infection. The recombinant Smcys10 protein showed binding and agglutinating activity in a Ca-dependent manner against bacteria. rSmcys10 treatment upregulated the expression of IL-10, TNF-α and TGF-β in macrophages of turbot and hindered the release of lactate dehydrogenase (LDH) from macrophages after V. anguillarum infection, which confirmed that rSmcys10 reduced the damage to macrophages by V. anguillarum. The NF-κB pathway was suppressed by Smcys10, as demonstrated by dual-luciferase analysis.
CONCLUSIONS
These results indicated that Smcys10 is involved in the host antibacterial immune response.
Topics: Animals; Flatfishes; Vibrio; Cystatins; Fish Proteins; Macrophages; Fish Diseases; Vibrio Infections; NF-kappa B; Cloning, Molecular; Gene Expression Regulation
PubMed: 38824265
DOI: 10.1007/s11033-024-09634-y -
Food Research International (Ottawa,... Jul 2024Vibrio parahaemolyticus and Vibrio vulnificus are bacteria with a significant public health impact. Identifying factors impacting their presence and concentrations in...
Vibrio parahaemolyticus and Vibrio vulnificus are bacteria with a significant public health impact. Identifying factors impacting their presence and concentrations in food sources could enable the identification of significant risk factors and prevent incidences of foodborne illness. In recent years, machine learning has shown promise in modeling microbial presence based on prevalent external and internal variables, such as environmental variables and gene presence/absence, respectively, particularly with the generation and availability of large amounts and diverse sources of data. Such analyses can prove useful in predicting microbial behavior in food systems, particularly under the influence of the constant changes in environmental variables. In this study, we tested the efficacy of six machine learning regression models (random forest, support vector machine, elastic net, neural network, k-nearest neighbors, and extreme gradient boosting) in predicting the relationship between environmental variables and total and pathogenic V. parahaemolyticus and V. vulnificus concentrations in seawater and oysters. In general, environmental variables were found to be reliable predictors of total and pathogenic V. parahaemolyticus and V. vulnificus concentrations in seawater, and pathogenic V. parahaemolyticus in oysters (Acceptable Prediction Zone >70 %) when analyzed using our machine learning models. SHapley Additive exPlanations, which was used to identify variables influencing Vibrio concentrations, identified chlorophyll a content, seawater salinity, seawater temperature, and turbidity as influential variables. It is important to note that different strains were differentially impacted by the same environmental variable, indicating the need for further research to study the causes and potential mechanisms of these variations. In conclusion, environmental variables could be important predictors of Vibrio growth and behavior in seafood. Moreover, the models developed in this study could prove invaluable in assessing and managing the risks associated with V. parahaemolyticus and V. vulnificus, particularly in the face of a changing environment.
Topics: Ostreidae; Machine Learning; Seawater; Vibrio parahaemolyticus; Animals; Vibrio vulnificus; Food Microbiology; Food Contamination; Shellfish; Seafood; Temperature; Vibrio
PubMed: 38823834
DOI: 10.1016/j.foodres.2024.114464 -
Cellular and Molecular Biology... May 2024Probiotics have been used successfully in aquaculture to enhance disease resistance, nutrition, and/or growth of cultured organisms. Six strains of Bacillus were...
Probiotics have been used successfully in aquaculture to enhance disease resistance, nutrition, and/or growth of cultured organisms. Six strains of Bacillus were isolated from the intestinal tracts of fish and recognised by conventional biochemical traits. The six isolated strains were Bacillus cereus and Bacillus subtilis using MALDI-TOF-MS technique. The probiotic properties of these Bacillus strains were studied. The tested bacillus strains exhibit antibacterial activity against the different pathogens. The strain S5 gave the important inhibition zones against most pathogens (20.5, 20.33, 23, and 21 mm against Vibrio alginolyticus, Vibrio parahaemolyticus, Staphylococcus aureus, and Salmonella typhimurium, respectively). According to our results, all Bacillus strains have extracellular components that can stop pathogenic bacteria from growing. The enzymatic characterization showed that the tested strains can produce several biotechnological enzymes such as α-glucosidase, naphtol-AS-BI-Phosphohydrolase, esterase lipase, acid phosphatase, alkaline phosphatase, amylase, lipase, caseinase, and lecithinase. All Bacillus strains were adhesive to polystyrene. The adding Bacillus strains to the Artemia culture exerted significantly greater effects on the survival of Artemia. The challenge test on Artemia culture showed that the protection against pathogenic Vibrio was improved. These findings allow us to recommend the examined strains as prospective probiotic options for the Artemia culture, which will be used as food additives to improve the culture conditions of crustacean larvae and marine fish.
Topics: Animals; Probiotics; Artemia; Bacillus; Gastrointestinal Tract; Fishes; Vibrio; Anti-Bacterial Agents; Antibiosis
PubMed: 38814235
DOI: 10.14715/cmb/2024.70.5.8 -
Antonie Van Leeuwenhoek May 2024Pseudoalteromonas piscicida 2515, isolated from Litopenaeus vannamei culture water, is a potential marine probiotic with broad anti-Vibrio properties. However, genomic...
Pseudoalteromonas piscicida 2515, isolated from Litopenaeus vannamei culture water, is a potential marine probiotic with broad anti-Vibrio properties. However, genomic information on P. piscicida 2515 is scarce. In this study, the general genomic characteristics and probiotic properties of the P. piscicida 2515 strain were analysed. In addition, we determined the antibacterial mechanism of this bacterial strain by scanning electron microscopy (SEM). The results indicated that the whole-genome sequence of P. piscicida 2515 contained one chromosome and one plasmid, including a total length of 5,541,406 bp with a G + C content of 43.24%, and 4679 protein-coding genes were predicted. Various adhesion-related genes, amino acid and vitamin metabolism and biosynthesis genes, and stress-responsive genes were found with genome mining tools. The presence of genes encoding chitin, bromocyclic peptides, lantibiotics, and sactipeptides showed the strong antibacterial activity of the P. piscicida 2515 strain. Moreover, in coculture with Vibrio anguillarum, P. piscicida 2515 displayed vesicle/pilus-like structures located on its surface that possibly participated in its bactericidal activity, representing an antibacterial mechanism. Additionally, 16 haemolytic genes and 3 antibiotic resistance genes, including tetracycline, fluoroquinolone, and carbapenem were annotated, but virulence genes encoding enterotoxin FM (entFM), cereulide (ces), and cytotoxin K were not detected. Further tests should be conducted to confirm the safety characteristics of P. piscicida 2515, including long-term toxicology tests, ecotoxicological assessment, and antibiotic resistance transfer risk assessment. Our results here revealed a new understanding of the probiotic properties and antibacterial mechanism of P. piscicida 2515, in addition to theoretical information for its application in aquaculture.
Topics: Pseudoalteromonas; Vibrio; Whole Genome Sequencing; Genome, Bacterial; Animals; Probiotics; Anti-Bacterial Agents; Penaeidae; Phylogeny; Base Composition
PubMed: 38809302
DOI: 10.1007/s10482-024-01974-w