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1.
Appl Environ Microbiol ; 89(1): e0187422, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36602323

RESUMO

Cyclic AMP (cAMP) receptor protein (CRP), encoded by crp, is a global regulator that is activated by cAMP, a second messenger synthesized by a class I adenylate cyclase (AC-I) encoded by cyaA in Escherichia coli. cAMP-CRP is required for growth on nonpreferred carbon sources and is a global regulator. We constructed in-frame nonpolar deletions of the crp and cyaA homologs in Vibrio parahaemolyticus and found that the Δcrp mutant did not grow in minimal media supplemented with nonpreferred carbon sources, but the ΔcyaA mutant grew similarly to the wild type. Bioinformatics analysis of the V. parahaemolyticus genome identified a 181-amino-acid protein annotated as a class IV adenylate cyclase (AC-IV) named CyaB, a member of the CYTH protein superfamily. AC-IV phylogeny showed that CyaB was present in Gammaproteobacteria and Alphaproteobacteria as well as Planctomycetes and Archaea. Only the bacterial CyaB proteins contained an N-terminal motif, HFxxxxExExK, indicative of adenylyl cyclase activity. Both V. parahaemolyticus cyaA and cyaB genes functionally complemented an E. coli ΔcyaA mutant. The Δcrp and ΔcyaB ΔcyaA mutants showed defects in growth on nonpreferred carbon sources and in swimming and swarming motility, indicating that cAMP-CRP is an activator. The ΔcyaA and ΔcyaB single mutants had no defects in these phenotypes, indicating that AC-IV complements AC-I. Capsule polysaccharide and biofilm production assays showed significant defects in the Δcrp, ΔcyaBΔcyaA, and ΔcyaB mutants, whereas the ΔcyaA strain behaved similarly to the wild type. This is consistent with a role of cAMP-CRP as an activator of these phenotypes and establishes a cellular role for AC-IV in capsule and biofilm formation, which to date has been unestablished. IMPORTANCE Here, we characterized the roles of CRP and CyaA in V. parahaemolyticus, showing that cAMP-CRP is an activator of metabolism, motility, capsule production, and biofilm formation. These results are in contrast to cAMP-CRP in V. cholerae, which represses capsule and biofilm formation. Previously, only an AC-I CyaA had been identified in Vibrio species. Our data showed that an AC-IV CyaB homolog is present in V. parahaemolyticus and is required for optimal growth. The data demonstrated that CyaB is essential for capsule production and biofilm formation, uncovering a physiological role of AC-IV in bacteria. The data showed that the cyaB gene was widespread among Vibrionaceae species and several other Gammaproteobacteria, but in general, its phylogenetic distribution was limited. Our phylogenetic analysis also demonstrated that in some species the cyaB gene was acquired by horizontal gene transfer.


Assuntos
Adenilil Ciclases , Vibrio parahaemolyticus , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Filogenia , AMP Cíclico/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteína Receptora de AMP Cíclico/genética , Proteína Receptora de AMP Cíclico/metabolismo , Biofilmes , Polissacarídeos
2.
Biosensors (Basel) ; 13(1)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36671946

RESUMO

A rapid and intuitive method for detecting Vibrio parahaemolyticus (VP) was established by a designed reaction vessel which coupled CRISPR/Cas12a with loop-mediated isothermal nucleic acid amplification (LAMP). There were two spaces in the vessel-holding LAMP reaction solution and CRISPR reaction solution, respectively, which were separated with a polyvinyl alcohol (PVA) membrane. The PVA membrane could be dissolved with a water solution. The thermolabile hemolysin (TLH) gene of VP was employed as the detection target. After the target sequence of the TLH gene was amplified with LAMP, the PVA membrane would be dissolved and the CRISPR reaction solution mixed with the LAMP reaction solution. In this way, amplicons could be detected with CRISPR/Cas12a in the reaction vessel. The fluorescent signals produced by the positive samples were clearly identified by the naked eye under a UV light, while the negative samples were dark. The whole detection procedure could be finished within 35 min with a detection limit of 100 copies/µL. The designed reaction vessel is easy to produce and can effectively prevent contamination due to the opening of the reaction vessel after the LAMP reaction. Thus, it will have the potential to provide a new solution for rapid detection in the field.


Assuntos
Álcool de Polivinil , Vibrio parahaemolyticus , Sistemas CRISPR-Cas , Técnicas de Amplificação de Ácido Nucleico/métodos , Vibrio parahaemolyticus/genética , Cateteres
3.
Int J Food Microbiol ; 387: 110059, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36580845

RESUMO

Exogenous applications of phage lysins against Vibrio parahaemolyticus (V. parahaemolyticus) are a challenge due to the gram-negative bacteria outer membrane barrier. This study aimed to improve the antibacterial effect of V. parahaemolyticus phage lysin Lysqdvp001 (Lys), the best-characterized lysin with lytic activity against multiple species of Vibrios, by using liposome delivery. Various kinds of Lys-loaded liposome (Lys-lip) systems were designed and tested. The antibacterial activities of cationic guar gum (CGG) containing liposomes were much higher than the other liposomes, causing >5 log10CFU/mL of reductions of V. parahaemolyticus in buffer and severely damaging the bacterial cell structure. Moreover, some CGG liposome formulations retained high antibacterial effect after both 60-80 °C heat treatments and freeze-drying. Besides, the most stable liposome formulation killed 99 % of V. parahaemolyticus in the seawater with live clams, and its depuration rate against the bacterial contaminated clams also reached 99 %.


Assuntos
Bacteriófagos , Bivalves , Vibrio parahaemolyticus , Animais , Lipossomos , Bivalves/microbiologia , Bactérias , Antibacterianos
4.
Virulence ; 14(1): 2156196, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36482737

RESUMO

Metals are nutrients essential for almost all lifeforms. Bacteria have evolved several mechanisms to overcome the metal restrictions imposed by the host. Vibrio parahaemolyticus causes severe threats to public health and significant economic losses in shrimp aquaculture. Herein, we report that ZrgA contributes to zinc acquisition in this pathogen. The operon VP_RS01455 to VP_RS01475 of V. parahaemolyticus encodes the putative Zn transporter ZrgABCDE, whose homologs are widely distributed in Vibrionaceae. RNA sequencing analysis revealed that V. parahaemolyticus modulates the transcriptome in response to Zn limitation. Genes in the Zinc uptake regulator (Zur) regulon are upregulated during Zn limitation, including three genes annotated to encode Zn-binding proteins. Significant upregulation of these three genes during Zn limitation was also confirmed by quantitative real-time PCR (qRT-PCR) analysis. However, only the mutants containing a VP_RS01470 (zrgA) deletion exhibited impaired growth under Zn-deficient conditions, indicating that VP_RS01470 plays the predominant role in V. parahaemolyticus Zn acquisition. The VP_RS01470 deletion mutant displayed a false appearance of decreased swimming motility under Zn-deficient conditions, as revealed by the fact that the polar flagellar-related genes were not downregulated in the mutant. Moreover, VP_RS01470 deletion produced no noticeable impact on the swarming motility and virulence in mice. qRT-PCR analysis and ß-galactosidase activity assays indicated that Zur negatively regulates VP_RS01470 expression in V. parahaemolyticus. Collectively, our findings suggest that ZrgA is required for Zn acquisition in V. parahaemolyticus and highlight the importance of detecting the expression of flagellar genes during analysis of motility of a mutant deficient in growth.


Assuntos
Vibrio parahaemolyticus , Animais , Camundongos , Vibrio parahaemolyticus/genética , Zinco/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Transporte/metabolismo , Transcriptoma , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
5.
Fish Shellfish Immunol ; 132: 108479, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36513322

RESUMO

Antimicrobial peptides (AMPs) constitute one of the most promising sources of natural molecules used for the design of effective antimicrobial agents alternative to antibiotics. Previously, we have showed that a crab proline-rich AMP designated as SpPR-AMP1 is a potent AMP that exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria. Here, we demonstrated the importance of SpPR-AMP1 peptide in treating a virulent acute hepatopancreatic necrosis disease (AHPND) Vibrio campbellii VH-639 isolate and eliciting the innate immune response to counter the AHPND infection in shrimp Litopenaeus vannamei. SpPR-AMP1 exhibited a strong antimicrobial activity against V. campbellii VH-639 at MIC value of 0.195-0.39 µM. Scanning electron microscopy (SEM) revealed the membrane disruption potential of SpPR-AMP1 against the V. campbellii VH-639 cells. The in vivo effect of SpPR-AMP1 in shrimp L.vannamei was investigated and the results showed that SpPR-AMP1 was capable of modulating the innate immune response by stimulating the expression levels of AMP transcripts in shrimp hemocytes. Moreover, treatments with SpPR-AMP1 could promote the resistance of shrimp against V. campbellii VH-639 infection as demonstrated by a significant increase in shrimp survival rate and decrease in both the bacterial load and the expression levels of bacterial PirA and PirB toxin gene transcripts in the infected shrimp. These results suggest the potential of SpPR-AMP1 peptide with the combined antimicrobial and immunoenhancing capabilities as promising antimicrobial agent to treat V. campbellii VH-639 causing AHPND infection in shrimp aquaculture.


Assuntos
Anti-Infecciosos , Penaeidae , Vibrioses , Vibrio parahaemolyticus , Animais , Antibacterianos/farmacologia , Vibrio parahaemolyticus/fisiologia , Peptídeos Antimicrobianos , Prolina/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Vibrioses/veterinária , Anti-Infecciosos/farmacologia
6.
Microb Pathog ; 174: 105947, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521654

RESUMO

Vibrio parahaemolyticus produces dual flagellar systems, i.e., the sheathed polar flagellum (Pof) and numerous lateral flagella (Laf), both of which are strictly regulated by numerous factors. QsvR is an AraC-type regulator that controls biofilm formation and virulence of V. parahaemolyticus. In the present study, we showed that deletion of qsvR significantly enhanced swimming motility of V. parahaemolyticus, while the swarming motility was not affected by QsvR. QsvR bound to the regulatory DNA regions of flgAMN and flgMN within the Pof gene loci to repress their transcription, whereas it negatively controls the transcription of flgBCDEFGHIJ and flgKL-flaC in an indirect manner. However, over-produced QsvR was also likely to possess the binding activity to the regulatory DNA regions of flgBCDEFGHIJ and flgKL-flaC in a heterologous host. In summary, this work demonstrated that QsvR negatively regulated the swimming motility of V. parahaemolyticus via directly action on the transcription of Pof genes.


Assuntos
Vibrio parahaemolyticus , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/metabolismo , Flagelos/genética , Flagelos/metabolismo , Genes Bacterianos , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
7.
Fish Shellfish Immunol ; 132: 108498, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36539168

RESUMO

White shrimp (Penaeus vannamei) is an important culture species in Taiwan but often encounters disease infection by Vibrio parahaemolyticus that cause acute hepatopancreatic necrosis disease (AHPND). This study investigates the effects of dietary supplementation of Leuconostoc mesenteroide B4 and its fermentate (dextran) on the immune response, intestinal morphology, disease resistance, and immune-related gene expression in white shrimp. In comparison to the control group, the shrimp fed with a diet containing B4+dextran (107 CFU B4/g feed and 0.05% dextran) for 14, 28, 42 and 56 days had a significantly higher feed efficiency, weight gain and specific growth rate. A significantly higher villus height in the intestine and higher survival rate after challenging with V. parahaemolyticus was recorded for the B4+dextran group. Flow cytometry analysis demonstrated that the group that had ingested B4+dextran had a higher total hemocyte count and a higher proportion of semi-granulocytes, but a lower percentage of granulocytes compared to the control group. The shotgun metagenomic results in the midgut revealed that Leuco. mesenteroides was barely found in the midgut of the shrimp, suggesting that this microbe and its transient presence in the midgut is not the direct mechanism underlying the improved shrimp growth in the treated sample. Instead, dextran, a key ingredient in the B4 fermentate, on the dynamic of the microbial populations in shrimp, possibly promoting the diversity of gut microbes, especially the beneficial microbes, and thereby rendering protection against AHPND. In terms of comparing the gene expression between the control and synbiotic groups, pre- and post-bacterial challenge, a higher expression level of immune genes was mostly found in the B4+dextran group after challenging it with V. parahaemolyticus (group B4+dextran-VP) in the hepatopancreas and hemocyte. In contrast, the transcript level of immune-related genes was found to be higher in the B4+dextran group than other combinations in the midgut. Taken together, this study found that dietary addition of synbiotic Leuco. mesenteroides B4 and dextran can improve the growth performance, intestinal morphology and microbiome, regulation of immune genes and disease resistance against V. parahaemolyticus infection in white shrimp.


Assuntos
Leuconostoc mesenteroides , Penaeidae , Simbióticos , Vibrio parahaemolyticus , Animais , Resistência à Doença , Vibrio parahaemolyticus/fisiologia , Dextranos/farmacologia , Imunidade Inata/genética
8.
Fish Shellfish Immunol ; 132: 108502, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36565998

RESUMO

Vibrio parahaemolyticus is a Gram-negative bacterium commonly found in marine and estuarine environments and is endemic among the global shrimp aquaculture industry. V. parahaemolyticus proteins PirA and PirB have been determined to be major virulence factors that contribute significantly to the development of acute hepatopancreatic necrosis disease. Our previous work had demonstrated the lethality of recombinant PirA and PirB proteins to Pacific white shrimp (Liptopenaeus vannamei). To understand the host response to these proteins, recombinant PirA and PirB proteins were administered using a reverse gavage method and individual shrimp were then sampled over time. Shrimp hepatopancreas libraries were generated and RNA sequencing was performed on the control and recombinant PirA/B-treated samples. Differentially expressed genes were identified among the assayed time points. Differentially expressed genes that were co-expressed at the later time points (2-, 4- and 6-h) were also identified and gene associations were established to predict functional physiological networks. Our analysis reveals that the recombinant PirA and PirB proteins have likely initiated an early host response involving several cell survival signaling and innate immune processes.


Assuntos
Penaeidae , Vibrio parahaemolyticus , Animais , Proteínas de Bactérias/genética , Vibrio parahaemolyticus/fisiologia , Fatores de Virulência , Aquicultura , Perfilação da Expressão Gênica/veterinária , Doença Aguda
9.
Environ Res ; 216(Pt 2): 114478, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206926

RESUMO

In this study, the effect of bay laurel (Laurus nobilis) (LE) and rosemary (Salvia rosmarinus) (RE) extracts, in two free forms and loaded with liposome, on the behavior of Listeria monocytogenes and Vibrio parahaemolyticus in silver carp (Hypophthalmichthys molitrix) minced, were examined. After extraction, the extracts were evaluated for phenolic, flavonoid, and antibacterial compounds (determination of MIC and MBC). The treatments studied included control treatment, treatments containing 1 and 1.5% of free extracts, and treatments containing 1 and 1.5% of liposome-coated extracts of LE and RE which were examined at times of 0, 4, 8, and 12 days with 3 replications. The findings indicated that the amount of flavonoid and phenolic compounds and the results of antibacterial tests (MIC and MBC tests) in RE extract were more favorable than LE extract. The aqueous extract of rosemary had higher levels of phenolic (344.66 mg gallic acid/g extract) and flavonoid (245.33 mg Catechin/g extract) compounds compared to the bay laurel extract (257.66 mg gallic acid/g extract) and (151.26 mg Catechin/g extract) respectively. The results of the behavior of L. monocytogenes and V. parahaemolyticus in fish showed that with increasing the storage time at 4 °C, these parameters increased, but in the treatment containing the coated forms of LE and RE extracts (concentration 1.5%), changes were significantly slower than other treatments. According to the obtained results, it can be concluded that in general, adding extracts of bay laurel and rosemary in a concentration of 1.5% reduces the proliferation of bacteria that cause food poisoning.


Assuntos
Carpas , Catequina , Laurus , Listeria monocytogenes , Rosmarinus , Salvia , Vibrio parahaemolyticus , Animais , Lipossomos/farmacologia , Catequina/farmacologia , Extratos Vegetais/farmacologia , Fenóis , Antibacterianos/farmacologia , Flavonoides/farmacologia , Ácido Gálico
10.
Infect Genet Evol ; 107: 105396, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549419

RESUMO

Vibrio parahaemolyticus is a gram-negative bacterium capable of causing diseases in humans and aquatic animals. The global relationships among V. parahaemolyticus genomes have been studied using multilocus sequence typing (MLST). Recently, the MLST gene recA has shown difficulties in amplification and/or a larger PCR fragment for some V. parahaemolyticus genomes due to genetic recombination. We aimed to investigate these recombination events of recA gene by analyzing 500 publicly available whole genomes from the NCBI database. The genomes with untypable recA genes were separated using BIGSdb and CGEMLST 2.0 servers, followed by annotation with RAST and NCBI pipelines. Moreover, the variable nature of V. parahaemolyticus was investigated by wgMLST analysis. The hypothetical proteins in recombinant regions were analyzed with VCIMPred tool. In the results, 3 genomes were detected with recA gene recombination, in which 2 were associated with phages and 1 to an AHPND causing strain. All 3 recombinant regions had a G + C content of 39%-40% with 15-30 ORFs, including a newly incorporated recA gene. These acquired recA genes were closely related to 3 different genera namely Aliivibrio, Photobacterium, and Vibrio. The wgMLST analysis indicated genetic recombination events occur independently among V. parahaemolyticus on a global scale. The in silico analysis revealed 4 hypothetical proteins associated with virulence factors in recombinant regions. The present study confirms, recombination events of V. parahaemolyticus recA gene, are diverse and may have an impact on the evolutionary process. Moreover, understanding these genetic recombination events of the recA gene is necessary to determine their STs and, therefore assessing epidemiological relationships.


Assuntos
Vibrioses , Vibrio parahaemolyticus , Animais , Humanos , Tipagem de Sequências Multilocus , Vibrio parahaemolyticus/genética , Filogenia , Recombinação Genética , Vibrioses/microbiologia
11.
Food Res Int ; 162(Pt A): 112026, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461246

RESUMO

Vibrio parahaemolyticus, is one of the most frequently reported pathogenic microorganisms that causes foodborne illnesses worldwide. The aims of the current study were to determine the prevalence, virulence genes, antimicrobial resistance, biofilm formation ability (BFA) and genetic characterization of V. parahaemolyticus recovered from retail aquatic products in Nanjing, China. There were 131 samples (71.6%) that tested positive for V. parahaemolyticus. The thermostable direct hemolysin-related hemolysin (trh) gene was found in two isolates (1.5%). Antimicrobial susceptibility tests showed that 46.6% of isolates were multidrug resistant. High resistance was observed to ampicillin (100%), cephalosporin (99.2%), trimethoprim/sulfamethoxazole (38.2%) and tetracycline (16.0%). Ten resistance patterns were found. The crystal violet staining assay showed that 35.1% had strong BFA, and 52.7% had intermediate BFA; notably, five (3.8%) extremely strong BFA strains were obtained from wet markets. According to whole genome sequencing analysis of 59 randomly selected isolates, 46 sequence types (STs) were identified, including 22 novel STs, and ST1042 was the dominant sequence type. It is clear that the V. parahaemolyticus population exhibits a high level of genetic variation. Our findings provide comprehensive insight into the prevalence and phylogenetic relationship of V. parahaemolyticus in aquatic products, suggesting potential hazards to consumers in Nanjing.


Assuntos
Vibrio parahaemolyticus , Vibrio parahaemolyticus/genética , Prevalência , Antibacterianos/farmacologia , Filogenia , Farmacorresistência Bacteriana/genética , China
12.
Food Res Int ; 162(Pt A): 112032, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461252

RESUMO

With the rapid development of logistics, a growing number of pathogenic microorganisms has the means to spread worldwide using food as a carrier; thus, there is an urgent need to develop effective detection strategies to ensure food safety. By combining novel markers identified by pan-genome analysis and a digital recombinase-aided amplification (RAA) detection method based on a microfluidic chip, a strategy of high-fidelity target-based microfluidic identification (HFTMI) has been developed. Herein, a proof-of-concept study of HFTMI for rapid pathogen detection of V. parahaemolyticus was investigated. Specific primers designed for the gene group_41170 identified in the pan-genome analysis showed high sensitivity and a broad spectrum for the detection of V. parahaemolyticus. Different power systems were investigated to increase the partition rate on specifically designed chamber-based digital chips. The performance of HFTMI was greatly improved compared with qPCR. Collectively, this novel HFTMI system provides more reliable guidance for food safety testing.


Assuntos
Vibrio parahaemolyticus , Vibrio parahaemolyticus/genética , Microfluídica , Primers do DNA , Excipientes , Alimentos
13.
Food Res Int ; 162(Pt A): 111986, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461295

RESUMO

Vibrio parahaemolyticus is a halophilic foodborne pathogen majorly isolated from seafood, threatening public health worldwide. However, our recent study reported the presence of this bacterium in freshwater crayfish, which were rarely identified and investigated. Its pathogenicity and genomic features remain unclear, and the controlling method to inhibit this bacterium in ready-to-eat (RTE) crayfish is not developed. Compared with a clinical strain (ATCC17802), the representative strain (LVP1) from freshwater crayfish showed higher pathogenicity in a zebrafish model, indicating its hypervirulence and foodborne infection risk. Unlike most clinical V. parahaemolyticus isolates that carried tdh and (or) trh, two classic virulence factor genes associated with clinical infections, the hypervirulent LVP1 lacked these two genes, indicating it is a novel strain and other unknown virulence factors play key roles in its pathogenicity. Genomic and phylogenetic analyses demonstrated this strain is V. parahaemolyticus, while it is phylogenetically distant from other global isolates. Therefore, LVP1 is considered a novel V. parahaemolyticus strain from freshwater crayfish, being hypervirulent, and lacking virulence marker genes. The antimicrobial resistant genes drfA6 and qnrV1 were unique in LVP1 and absent in other reference V. parahaemolyticus strains. Antimicrobial susceptibility testing confirms it as multidrug resistance, with resistance to ampicillin, amoxicillin/clavulanate, trimethoprim, and colistin. To control this novel and multidrug-resistant V. parahaemolyticus strain in food production chains, we developed a phage cocktail and applied it to the surface of RTE crayfish meat, resulting in a significant decrease in the bacterial load by 2.36 log10 CFU/mL. These data highlight freshwater food products pose threats to public health through 'farm-to-fork' transmission of hypervirulent V. parahaemolyticus and reveal the phage cocktail as a promising method to attenuate this bacterium in RTE food, emphasizing the necessity to prevent food contamination caused by this bacterium from freshwater products.


Assuntos
Anti-Infecciosos , Bacteriófagos , Vibrio parahaemolyticus , Animais , Astacoidea , Bacteriófagos/genética , Filogenia , Peixe-Zebra , Alimentos Marinhos , Água Doce , Fatores de Virulência/genética
14.
Environ Monit Assess ; 195(1): 229, 2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36565404

RESUMO

Vibrio parahaemolyticus (V.p) is a marine pathogenic bacterium that poses a high risk to human health and shellfish industry, yet an effective regional-scale nowcasting model for managing the risk remains lacking. This study presents the first regional-scale model for nowcasting the level of V.p in oysters in the marine environment by developing an ensemble modeling approach. The ensemble modeling approach involves the integration of genetic programming (GP) and deep artificial neural networks (DNN)-based modeling. The new approach was demonstrated by developing three GP-DNN ensemble models for predicting the V.p level in North Carolina, New Hampshire, and the combined region. Specifically, GP was employed to establish nonlinear functions between the V.p level and antecedent conditions of environmental variables. The nonlinear GP functions and current conditions of individual environmental variables were then utilized as inputs into a DNN model, forming a GP-DNN ensemble model. Modeling results indicated that the GP-DNN ensemble models were capable of predicting the V.p level with the correlation coefficient of 0.91, 0.90, and 0.80 for North Carolina, New Hampshire, and the combined region, respectively, demonstrating the impact of distinct environmental conditions in the local areas on accuracy of the combined regional-scale model. Sensitivity analysis results showed that sea surface temperature and sea surface salinity are the two most important environmental predictors for the abundance of V.p in oysters, followed by water level, pH, chlorophyll-a, and turbidity. The findings suggested that the GP-DNN ensemble models could be utilized as effective predictive tools for mitigating the V.p risk.


Assuntos
Aprendizado Profundo , Ostreidae , Vibrio parahaemolyticus , Animais , Humanos , Monitoramento Ambiental , Ostreidae/microbiologia , Frutos do Mar/análise
15.
Cell Rep ; 41(10): 111732, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36476863

RESUMO

The rearrangement hotspot (Rhs) repeat is an ancient giant protein fold found in all domains of life. Rhs proteins are polymorphic toxins that could either be deployed as an ABC complex or via a type VI secretion system (T6SS) in interbacterial competitions. To explore the mechanism of T6SS-delivered Rhs toxins, we used the gastroenteritis-associated Vibrio parahaemolyticus as a model organism and identified an Rhs toxin-immunity pair, RhsP-RhsPI. Our data show that RhsP-dependent prey targeting by V. parahaemolyticus requires T6SS2. RhsP can bind to VgrG2 independently without a chaperone and spontaneously self-cleaves into three fragments. The toxic C-terminal fragment (RhsPC) can bind to VgrG2 via a VgrG2-interacting region (VIR). Our electron microscopy (EM) analysis reveals that the VIR is encapsulated inside the Rhs ß barrel structure and that autoproteolysis triggers a dramatic conformational change of the VIR. This alternative VIR conformation promotes RhsP dimerization, which significantly contributes to T6SS2-mediated prey targeting by V. parahaemolyticus.


Assuntos
Sistemas de Secreção Tipo VI , Vibrio parahaemolyticus
16.
Arch Microbiol ; 205(1): 41, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36571636

RESUMO

For the sustainable farming of disease-free and healthy shrimps, antimicrobial use is frequent nowadays in shrimp-cultured system. Considering the serious impact of global antimicrobial resistance (AMR), the present study was focused to investigate the prevalence of antimicrobial-resistant vibrios among infected shrimps (Penaeus vannamei) from two brackish water-cultured farms. Diverse species of vibrios viz. V. alginolyticus, V. parahaemolyticus, V. cholerae, V. mimicus, and V. fluvialis along with Aeromonas hydrophila, A. salmonicida and Shewanella algae were recovered from the shrimps on TCBS medium. Shannon-Wiener diversity index and H' (loge) were 1.506 and 1.69 for the isolates from farm 1 and farm 2, respectively. V. alginolyticus was found to be the most resistant isolate by showing multiple antibiotic resistance (MAR) index of 0.60 followed by V. mimicus (0.54) and V. parahaemolyticus (0.42). Among the 35 antibiotics of 15 different classes tested, tetracyclines, beta-lactams and cephalosporins were found as the most resistant antibiotic classes. All the isolates possessed a MAR index > 0.2 and the majority exhibited minimum inhibitory concentration (MIC) > 256 mcg/ml, thereby indicating the excess exposure of antibiotics in the systems. An enhanced altered resistance phenotype and a significant shift in the MAR index were noticed after plasmid curing. Public health is further concerning because plasmid-borne AMR is evident among the isolates and the studied shrimp samples are significant in the food industry. This baseline information will help the authorities to curb antimicrobial use and pave the way for establishing new alternative strategies by undertaking a multidimensional "One-Health" approach.


Assuntos
Anti-Infecciosos , Penaeidae , Vibrio cholerae , Vibrio parahaemolyticus , Vibrio , Animais , Antibacterianos/farmacologia
17.
Front Cell Infect Microbiol ; 12: 1035364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339346

RESUMO

Vibrio parahaemolyticus is a common pathogen usually controlled by antibiotics in mariculture. Notably, traditional antibiotic therapy is becoming less effective because of the emergence of bacterial resistance, hence new strategies need to be found to overcome this challenge. Bacteriophages, a class of viruses that lyse bacteria, can help us control drug-resistant bacteria. In this study, a novel Vibrio parahaemolyticus phage phiTY18 isolated from the coastal water of Xiamen was explored. Transmission electron microscopy showed that phiTY18 had an icosahedral head of 130.0 ± 1.2 nm diameter and a contractile tail of length of 66.7 ± 0.6 nm. The phage titer could reach 7.2×1010 PFU/mL at the optimal MOI (0.01). The phage phiTY18 had a degree of tolerance to heat and acid and base. At the temperature of 50°C (pH7.0, 1h) the survival phages reached 1.28×106 PFU/mL, and at pH 5-9 (30°C, 1h), the survival phages was greater than 6.37×107 PFU/mL Analysis of the phage one-step growth curve revealed that it had a latent period of 10min, a rise period of 10min, and an average burst size of the phage was 48 PFU/cell. Genome sequencing and analysis drew that phage phiTY18 had double-stranded DNA (191,500 bp) with 34.90% G+C content and contained 117 open reading frames (ORFs) and 24 tRNAs. Phylogenetic tree based on major capsid protein (MCP) revealed that phage phiTY18 (MW451250) was highly related to two Vibrio phages phiKT1024 (OM249648) and Va1 (MK387337). The NCBI alignment results showed that the nucleotide sequence identity was 97% and 93%, respectively. In addition, proteomic tree analysis indicated that phage phiTY18, phiKT1024, and Va1 were belong to the same virus sub-cluster within Myoviridae. This study provides a theoretical basis for understanding the genomic characteristics and the interaction between Vibrio parahaemolyticus phages and their host.


Assuntos
Bacteriófagos , Vibrio parahaemolyticus , Bacteriófagos/genética , Vibrio parahaemolyticus/genética , Filogenia , Proteômica , Genoma Viral , Genômica , Fases de Leitura Aberta , Água
18.
PLoS One ; 17(11): e0277203, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36342937

RESUMO

To estimate the incidence of foodborne gastroenteritis caused by nontyphoidal Salmonella enterica, Shigella, and Vibrio parahaemolyticus in China, population surveys and sentinel hospital surveillance were implemented in six provinces from July 2010 to July 2011, and a multiplier calculation model for the burden of disease was constructed. The multiplier for salmonellosis and V. parahaemolyticus gastroenteritis was estimated at 4,137 [95% confidence interval (CI) 2,320-5,663], and for shigellosis at 4,356 (95% CI 2,443-5,963). Annual incidence per 100,000 population was estimated as 245 (95% CI 138-336), 67 (95% CI 38-92), and 806 (95% CI 452-1,103) for foodborne salmonellosis, shigellosis, and V. parahaemolyticus gastroenteritis, respectively, indicating that foodborne infection caused by these three pathogens constitutes an important burden to the Chinese healthcare system. Continuous implementation of active surveillance of foodborne diseases, combined with multiplier models to estimate disease burden, makes it possible for us to better understand food safety status in China.


Assuntos
Disenteria Bacilar , Doenças Transmitidas por Alimentos , Gastroenterite , Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Salmonella enterica , Shigella , Vibrio parahaemolyticus , Humanos , Disenteria Bacilar/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Gastroenterite/epidemiologia , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia , China/epidemiologia
19.
J Water Health ; 20(2): 369-384, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36366993

RESUMO

Vibrio parahaemolyticus is a gram-negative bacterium ubiquitous in seawater or estuarine water throughout the world. It is a major cause of seafood gastroenteritis complications. In this study, the presence of V. parahaemolyticus was investigated in 66 seawater samples collected during 2018 from 15 stations spread along the Tunisian coast using selective media including CHROMagar Vibrio media. The results show that only eight samples contained V. parahaemolyticus. However, while Vibrio alginolyticus was detected in all samples; both Vibrio cholerae and Vibrio vulnificus were not found. Nine of the presumed V. parahaemolyticus colonies were purified on tryptic soy agar from eight positive samples then identified by the API 20E biochemical test and confirmed by the presence of a specific target toxR gene. The detection of virulence genes, thermostable direct haemolysin (tdh) and thermostable-related haemolysin (trh), by the polymerase chain reaction (PCR) showed the presence of only two trh-positive isolates. The assessment of antibiotic susceptibility of the V. parahaemolyticus isolated revealed a complete resistance to colistin, amikacin, penicillin and cefotaxime and a total sensitivity to chloramphenicol, nitrofurantoin and sulfamethoxazole-trimethoprim with a multiple antibiotic resistance index (MAR) ranging from 0.4 to 0.5.


Assuntos
Vibrio cholerae , Vibrio parahaemolyticus , Alimentos Marinhos/microbiologia , Resistência Microbiana a Medicamentos , Água do Mar/microbiologia , Vibrio cholerae/genética
20.
Mar Drugs ; 20(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36355025

RESUMO

To explore the application of chitosan-gentamicin conjugate (CS-GT) in inhibiting Vibrio parahaemolyticus (V. parahaemolyticus), which is an important pathogen in aquatic animals worldwide, the antimicrobial activity of CS-GT and the effects of a CS-GT dose on the intestine histopathology and intestinal flora of V. parahaemolyticus-infected shrimps were explored. The results showed that CS-GT possessed broad-spectrum antibacterial activity, with minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and half inhibitory concentration (IC50) of 20.00 ± 0.01, 75.00 ± 0.02 and 18.72 ± 3.17 µg/mL for V. parahaemolyticus, respectively. Further scanning electron microscope and cell membrane damage analyses displayed that the electrostatic interaction of CS-GT with cell membrane strengthened after CS grafted GT, resulting in leakage of nucleic acid and electrolytes of V. parahaemolyticus. On the other hand, histopathology investigation indicated that high (100 mg/kg) and medium (50 mg/kg) doses of CS-GT could alleviate the injury of a shrimp's intestine caused by V. parahaemolyticus. Further 16S rRNA gene sequencing analysis found high and medium dose of CS-GT could effectively inhabit V. parahaemolyticus invasion and reduce intestinal dysfunction. In conclusion, CS-GT possesses good antibacterial activity and could protect shrimps from pathogenic bacteria infection.


Assuntos
Quitosana , Microbioma Gastrointestinal , Penaeidae , Vibrio parahaemolyticus , Animais , Quitosana/farmacologia , Quitosana/metabolismo , Gentamicinas/farmacologia , RNA Ribossômico 16S/metabolismo , Penaeidae/genética , Antibacterianos/farmacologia , Antibacterianos/metabolismo
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