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1.
ISME Commun ; 4(1): ycae041, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38707842

RESUMEN

In response to climate change, the nature of endophytes and their applications in sustainable agriculture have attracted the attention of academics and agro-industries. This work focused on the endophytic halophiles of the endangered Taiwanese salt marsh plant, Bolboschoenus planiculmis, and evaluated the functions of these isolates through in planta salinity stress alleviation assay using Arabidopsis. The endophytic strain Priestia megaterium BP01R2, which can promote plant growth and salinity tolerance, was further characterized through multi-omics approaches. The transcriptomics results suggested that BP01R2 could function by tuning hormone signal transduction, energy-producing metabolism, multiple stress responses, etc. In addition, the cyclodipeptide cyclo(L-Ala-Gly), which was identified by metabolomics analysis, was confirmed to contribute to the alleviation of salinity stress in stressed plants via exogenous supplementation. In this study, we used multi-omics approaches to investigate the genomics, metabolomics, and tropisms of endophytes, as well as the transcriptomics of plants in response to the endophyte. The results revealed the potential molecular mechanisms underlying the occurrence of biostimulant-based plant-endophyte symbioses with possible application in sustainable agriculture.

2.
Antioxidants (Basel) ; 13(3)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38539869

RESUMEN

This study represents a primary investigation centered on screening six marine fungi, Emericellopsis maritima, Engyodontium album, Hypomontagnella monticulosa, Hortaea werneckii, Trichoderma harzianum, and Aspergillus sp.7, associated with the red algae Pterocladiella capillacea, which was collected from Chao-Jin Park in Keelung, Taiwan, as potential immunostimulants for shrimp aquaculture. Recognizing the imperative for novel strategies to combat pathogen resistance arising from the use of antibiotics and vaccines in aquaculture, this study aimed to evaluate the metabolomic profile, antioxidant capabilities, and antibacterial properties of marine fungi. The antibacterial activity of the fungal extract was evaluated against five major aquaculture pathogens: Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Enterobacter aeruginosa, and Vibrio parahaemolyticus. The viability and cytotoxicity of marine fungal extracts were preliminarily evaluated using brine shrimps before assessing cytotoxicity, growth performance, immune efficacy, and disease resistance in white shrimp. The present study demonstrated that total phytochemical analysis correlated with antioxidant activity. Emericellopsis maritima and Trichoderma harzianum exhibited the strongest DPPH antioxidant scavenging activities of half-maximal inhibitory concentration (IC50) 16.5 ± 1.2 and 12.2 ± 2.6, which are comparable to ascorbic acid. LC-HDMSE analysis of the marine fungal extracts identified more than 8000 metabolites mainly classified under the superclass level of organic oxygen compounds, Organoheterocyclic compounds, Phenylpropanoids and polyketides, alkaloid and derivatives, benzenoids, lignans and neolignans, lipid and lipid-like molecules, nucleotides and nucleosides, organic nitrogen compounds, and organic acids and derivatives. Overall, our study significantly contributes to the advancement of sustainable practices by exploring alternative antimicrobial solutions and harnessing the bioactive potential inherent in marine endophytic fungi. In conclusion, our study advances our comprehension of fungal communities and their applications and holds promise for the development of effective and environmentally friendly approaches for enhancing shrimp health and productivity.

3.
Antonie Van Leeuwenhoek ; 117(1): 49, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38448684

RESUMEN

A marine bacterial strain, named NTOU-MSR1T, was isolated from marine sediment of northern coast of Taiwan. This bacterium was Gram-stain-negative, aerobic, and motile, with a single flagellum. Its rod-shaped cells measured approximately 0.5-0.6 µm in width and 1.8-2.0 µm in length. NTOU-MSR1T grew at temperatures ranging from 10 to 45 °C, optimally at 30 °C. The pH range for growth was 7.0-10.0, with optimal growth at pH 7.0-8.0. It tolerated NaCl concentrations up to 12%. The cell membrane predominantly contained fatty acids such C16:1ω7c, C18:1ω7c, and C16:0. The overall genome relatedness indices indicated that strain NTOU-MSR1T had an average nucleotide identity (ANI) of 87.88% and a digital DNA-DNA hybridization (dDDH) value of 35.40% compared to its closest related species, O. marisflavi 102-Na3T. These values fell below the 95% and 70% threshold for species delineation, respectively. These findings suggested that the strain NTOU-MSR1T was a new member of the Oceanimonas genus. Its genomic DNA had a G + C content of 61.0 mol%. Genomic analysis revealed genes associated with the catechol branch of ß- ketoadipate pathway for degrading polycyclic aromatic hydrocarbons, resistance to heavy metal, biosynthesis of polyhydroxybutyrate and the production of glycoside hydrolases (GH19, GH23, and GH103) for chitin and glycan digestion. Additionally, NTOU-MSR1T was capable of synthesizing biosurfactants and potentially degrading plastic. The proposed name for this new species is Oceanimonas pelagia, with the type strain designated as NTOU-MSR1T (= BCRC 81403T = JCM 36023T).


Asunto(s)
Bacterias , Flagelos , Membrana Celular , Sedimentos Geológicos , ADN
4.
Commun Biol ; 5(1): 454, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35551233

RESUMEN

Bacterial polyynes are highly active natural products with a broad spectrum of antimicrobial activities. However, their detailed mechanism of action remains unclear. By integrating comparative genomics, transcriptomics, functional genetics, and metabolomics analysis, we identified a unique polyyne resistance gene, masL (encoding acetyl-CoA acetyltransferase), in the biosynthesis gene cluster of antifungal polyynes (massilin A 1, massilin B 2, collimonin C 3, and collimonin D 4) of Massilia sp. YMA4. Crystallographic analysis indicated that bacterial polyynes serve as covalent inhibitors of acetyl-CoA acetyltransferase. Moreover, we confirmed that the bacterial polyynes disrupted cell membrane integrity and inhibited the cell viability of Candida albicans by targeting ERG10, the homolog of MasL. Thus, this study demonstrated that acetyl-CoA acetyltransferase is a potential target for developing antifungal agents.


Asunto(s)
Acetil-CoA C-Acetiltransferasa , Antifúngicos , Acetil-CoA C-Acetiltransferasa/genética , Acetil-CoA C-Acetiltransferasa/metabolismo , Antifúngicos/farmacología , Bacterias/metabolismo , Candida albicans/genética , Candida albicans/metabolismo , Poliinos/metabolismo , Poliinos/farmacología
5.
J Hazard Mater ; 434: 128870, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35452977

RESUMEN

Phytoextraction is a cost-effective and eco-friendly technology to remove arsenic (As) from contaminated soil using plants and associated microorganisms. Pteris vittata is the most studied As hyperaccumulator, which effectively takes up inorganic arsenate via roots. Arsenic solubilization and speciation occur prior to plant absorption in the rhizosphere, which play a key role in As phytoextraction by P. vittata. This study investigated the metabolomic correlation of P. vittata and associated rhizospheric microorganisms during As phytoextraction. Three-month pot cultivation of P. vittata in As polluted soil was conducted. In rhizosphere, an increase of water-soluble As concentration and a decrease of pH was observed in the second month, suggesting acidic metabolites as a possible cause of As solubilization. A correlation network was built to elucidate the interactions among metabolites, bacteria and fungi in the rhizosphere of P. vittata. Our results demonstrate that the plant is the major driving force of rhizospheric microbiota generation, and both microbial community and metabolites in rhizosphere of P. vittata correlate to increased bioavailable As. Multi-omics analysis revealed that pterosins enrich microbes that potentially promote As phytoextraction. This study extends the current view of rhizospheric plant-microbes synergistic effects of hyperaccumulators on phytoextraction, which provides clues for developing efficient As phytoremediation approaches.


Asunto(s)
Arsénico , Pteris , Contaminantes del Suelo , Arsénico/metabolismo , Biodegradación Ambiental , Raíces de Plantas/metabolismo , Pteris/metabolismo , Suelo/química , Contaminantes del Suelo/metabolismo
6.
Environ Microbiol ; 24(1): 276-297, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34863027

RESUMEN

Brown root rot (BRR) caused by Phellinus noxius is a destructive tree disease in tropical and subtropical areas. To understand how BRR affects the composition of the plant rhizoplane-enriched microbiota, the microbiomes within five root-associated compartments (i.e., bulk soil, old/young root rhizosphere soil, old/young root tissue) of Ficus trees naturally infected by P. noxius were investigated. The level of P. noxius infection was determined by quantitative PCR. Illumina sequencing of the internal transcribed spacer and 16S rRNA revealed that P. noxius infection caused a significant reduction in fungal diversity in the bulk soil, the old root rhizosphere soil, and the old root tissue. Interestingly, Cosmospora was the only fungal genus positively correlated with P. noxius. The abundance and composition of dominant bacterial taxa such as Actinomadura, Bacillus, Rhodoplanes, and Streptomyces differed between BRR-diseased and healthy samples. Furthermore, 838 isolates belonging to 26 fungal and 35 bacterial genera were isolated and tested for interactions with P. noxius. Antagonistic activities were observed for isolates of Bacillus, Pseudomonas, Aspergillus, Penicillium, and Trichoderma. Cellophane overlay and cellulose/lignin utilization assays suggested that Cosmospora could tolerate the secretions of P. noxius and that the degradation of lignin by P. noxius may create suitable conditions for Cosmorpora growth.


Asunto(s)
Ficus , Microbiota , Trichoderma , Basidiomycota , Microbiota/genética , Enfermedades de las Plantas/microbiología , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Rizosfera , Microbiología del Suelo , Árboles/microbiología
7.
mSystems ; 6(4): e0074821, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34427528

RESUMEN

Culturing unculturable bacteria is a classic microbiology challenge; to successfully culture unculturable bacteria, microbiologists work hard to create hundreds of culture conditions. To improve the success rate and efficiency of culturing a broad spectrum of environmental microbes, it is helpful to know more about the microbial community composition. Shortening the amount of time spent sequencing, analyzing sequencing data, and predicting suitable culture conditions seems to be a critical step for improving knowledge of microbes in environmental samples and expanding culture collections. In this commentary, we introduce potential strategies using rapid and portable sequencing devices to help scientists design and plan for specific microbial culture media on their way back to the laboratory. Rapid metagenomic sequencing approaches and real-time analysis make it possible to choose microbes we are interested in and discover novel microbes in environments for cultivation.

8.
Mar Drugs ; 19(4)2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33918939

RESUMEN

Empedopeptins-eight amino acid cyclic lipopeptides-are calcium-dependent antibiotics that act against Gram-positive bacteria such as Staphylococcus aureus by inhibiting cell wall biosynthesis. However, to date, the biosynthetic mechanism of the empedopeptins has not been well identified. Through comparative genomics and metabolomics analysis, we identified empedopeptin and its new analogs from a marine bacterium, Massilia sp. YMA4. We then unveiled the empedopeptin biosynthetic gene cluster. The core nonribosomal peptide gene null-mutant strains (ΔempC, ΔempD, and ΔempE) could not produce empedopeptin, while dioxygenase gene null-mutant strains (ΔempA and ΔempB) produced several unique empedopeptin analogs. However, the antibiotic activity of ΔempA and ΔempB was significantly reduced compared with the wild-type, demonstrating that the hydroxylated amino acid residues of empedopeptin and its analogs are important to their antibiotic activity. Furthermore, we found seven bacterial strains that could produce empedopeptin-like cyclic lipopeptides using a genome mining approach. In summary, this study demonstrated that an integrated omics strategy can facilitate the discovery of potential bioactive metabolites from microbial sources without further isolation and purification.


Asunto(s)
Antibacterianos/biosíntesis , Proteínas Bacterianas/biosíntesis , Genómica , Lipopéptidos/biosíntesis , Metabolómica , Oxalobacteraceae/metabolismo , Péptidos Cíclicos/biosíntesis , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Biología Computacional , Minería de Datos , Regulación Bacteriana de la Expresión Génica , Lipopéptidos/genética , Lipopéptidos/farmacología , Estructura Molecular , Familia de Multigenes , Oligopéptidos/biosíntesis , Oligopéptidos/genética , Oligopéptidos/farmacología , Oxalobacteraceae/genética , Péptidos Cíclicos/genética , Péptidos Cíclicos/farmacología , Biosíntesis de Proteínas , Proteómica , Metabolismo Secundario , Relación Estructura-Actividad
9.
ISME J ; 15(6): 1858-1861, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33619352

RESUMEN

Bacteria and fungi secrete many natural products that inhibit each other's growth and development. The dynamic changes in secreted metabolites that occur during interactions between bacteria and fungi are complicated. Pyochelin is a siderophore produced by many Pseudomonas and Burkholderia species that induces systemic resistance in plants and has been identified as an antifungal agent. Through imaging mass spectrometry and metabolomics analysis, we found that Phellinus noxius, a plant pathogen, can modify pyochelin and ent-pyochelin to an esterification product, resulting in reduced iron-chelation and loss of antifungal activity. We also observed that dehydroergosterol peroxide, the fungal metabolite, is only accumulated in the presence of pyochelin produced through bacteria-fungi interactions. For the first time, we show the fungal transformation of pyochelin in the microbial interaction. Our findings highlight the importance of understanding the dynamic changes of metabolites in microbial interactions and their influences on microbial communities.


Asunto(s)
Antifúngicos , Sideróforos , Antifúngicos/farmacología , Hongos , Hierro , Pseudomonas , Pseudomonas aeruginosa
10.
Sci Total Environ ; 740: 140137, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-32927575

RESUMEN

Phytoremediation is a promising inexpensive method of detoxifying arsenic (As) contaminated soils using plants and associated soil microorganisms. The potential of Pteris vittata to hyperaccumulate As contamination has been investigated widely. Since As(V) is efficiently taken up by P. vittata than As(III), As speciation by associated rhizobacteria could offer enormous possibility to enhance As phytoremediation. Specifically, increased rhizobacteria mediated As(III) to As(V) conversion appeared to be a crucial step in As mobilization and translocation. In this study, Pseudomonasvancouverensis strain m318 with the potential to improve As phytoremediation was inoculated to P. vittata in a field trial for three years to evaluate its long-term efficacy and stability for enhancing As phytoextraction. The biomass, As concentration, and As accumulation of ferns showed to be increased by inoculation treatment. Although this trend occasionally declined which may be accounted to lower As concentration in soil and amount of precipitation during experiments, the potential of inoculation was observed in increased enrichment coefficients. Further, the arsenite oxidase (aioA-like) genes in the rhizosphere were detected to evaluate the influence of inoculation on As phytoremediation. The findings of this study suggested the potential application of rhizosphere regulation to improve phytoremediation technologies for As contaminated soils. However, the conditions which set the efficacy of this method could be further optimized.


Asunto(s)
Arsénico/análisis , Pteris , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Rizosfera
11.
Sci Total Environ ; 712: 134504, 2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-31831229

RESUMEN

Pteris vittata and Pteris multifida are widely studied As hyperaccumulators that absorb As mainly via roots. Hence, rhizobacteria exhibit promising potential in phytoextraction owing to their immense microbial diversity and interactions with plants. Pseudomonas vancouverensis strain m318 that contains aioA-like genes was screened from P. multifida's rhizosphere through the high As resistance (minimum inhibitory concentrations (MICs) against As(III): 16 mM; MICs against As(V): 320 mM), rapid As oxidation (98% oxidation by bacterial cultures (OD600nm = 1) from 200 µL of 0.1 mM As(III) within 24 h), predominant secretion of IAA (12.45 mg L-1) and siderophores (siderophore unit: 88%). Strain m318 showed significant chemotactic response and high colonization efficiency to P. vittata roots, which suggested its wide host affinity. Interestingly, inoculation with strain m318 enhanced the proportion of aioA-like genes in the rhizosphere. And in field trials, inoculation with strain m318 increased As accumulation in P. vittata by 48-146% and in P. multifida by 42-233%. Post-transplantation inoculations also increased As accumulation in both ferns. The abilities of the isolated multifunctional strain m318 and the increase in the rhizosphere microbial aioA-like genes are thus speculated to be involved in As transformation in the rhizospheres and roots of P. vittata and P. multifida.


Asunto(s)
Helechos , Arsénico , Biodegradación Ambiental , Rizosfera , Contaminantes del Suelo
12.
Ecotoxicol Environ Saf ; 190: 110075, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31881405

RESUMEN

As a toxic and carcinogenic metalloid, arsenic has posed serious threat to human health. Phytoremediation has emerged as a promising approach to circumvent this problem. Arsenic uptake by Pteris vittata is largely determined by arsenic speciation and mainly occurs via roots; thus, rhizospheric microbial activities may play a key role in arsenic accumulation. The aim of this study was to investigate the potential of arsenic resistant rhizobacteria to enhance arsenic phytoextraction. A total of 49 cultivable rhizobacteria were isolated from the arsenic hyperaccumulating fern, Pteris vittata, and subjected to an initial analysis to identify potentially useful traits for arsenic phytoextraction, such as arsenic resistance and the presence of aioA(aroA)-like (arsenite oxidase-like) gene. Isolated strain r507, named as Cupriavidus basilensis strain r507, was a selected candidate for its outstanding arsenic tolerance, rapid arsenite oxidation ability, and strong colonization to P. vittata. Strain r507 was used in co-cultivation trials with P. vittata in the field for six months. Results showed that the inoculation with strain r507 potentiated As accumulation of P. vittata up to 171%. Molecular analysis confirmed that the inoculation increased the abundance of aioA-like genes in the rhizosphere, which might have facilitated arsenite oxidation and absorption. The findings of this study suggested the feasibility of co-cultivating hyperaccumulators with facilitator bacteria for practical arsenic phytoremediation.


Asunto(s)
Arsénico/metabolismo , Cupriavidus/metabolismo , Pteris/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Transporte Biológico , Oxidación-Reducción , Raíces de Plantas/metabolismo , Rizosfera
13.
Microorganisms ; 7(11)2019 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-31744069

RESUMEN

A novel TnMERI1-like transposon designated as TnMARS1 was identified from mercury resistant Bacilli isolated from Minamata Bay sediment. Two adjacent ars operon-like gene clusters, ars1 and ars2, flanked by a pair of 78-bp inverted repeat sequences, which resulted in a 13.8-kbp transposon-like fragment, were found to be sandwiched between two transposable genes of the TnMERI1-like transposon of a mercury resistant bacterium, Bacillus sp. MB24. The presence of a single transcription start site in each cluster determined by 5'-RACE suggested that both are operons. Quantitative real time RT-PCR showed that the transcription of the arsR genes contained in each operon was induced by arsenite, while arsR2 responded to arsenite more sensitively and strikingly than arsR1 did. Further, arsenic resistance complementary experiments showed that the ars2 operon conferred arsenate and arsenite resistance to an arsB-knocked out Bacillus host, while the ars1 operon only raised arsenite resistance slightly. This transposon nested in TnMARS1 was designated as TnARS1. Multi-gene cluster blast against bacteria and Bacilli whole genome sequence databases suggested that TnMARS1 is the first case of a TnMERI1-like transposon combined with an arsenic resistance transposon. The findings of this study suggested that TnMERI1-like transposons could recruit other mobile elements into its genetic structure, and subsequently cause horizontal dissemination of both mercury and arsenic resistances among Bacilli in Minamata Bay.

14.
Sci Total Environ ; 624: 106-113, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29248701

RESUMEN

Salmonella is one of the most common pathogens of waterborne and foodborne disease-causing pathogens. In this study, we collected 172 surface water samples from Puzih River and Kaoping River between the years 2010 and 2011. Salmonella was detected in 31.7% (32/101) and 42.2% (30/71) of the samples from the two rivers, respectively. From these positive samples, 44 Salmonella isolates were obtained from these positive samples and were characterized using serotyping and pulsed-field gel electrophoresis (PFGE) genotyping. The isolates were found with 17 serovars and 32 PFGE patterns. Salmonella enterica Newport, Bareilly, Kedougou, Albany and subspecies IIIb 50:k:z were the five most common serovars in aquatic environmental Salmonella isolates. In addition, of the total clinical samples from Chiayi and Kaohsiung, 33.7% (60/178) Newport serovars were isolated. After conducting categorical analysis, we found that the serovar Newport was not uniformly distributed cross the cities. The serovar Newport was over-represented (p<0.001) among human isolates in Chiayi and Kaohsiung. To investigate the association between Salmonella isolates from aquatic environment and human samples, we compared the environmental PFGE patterns of the test samples with those of 2438 clinical isolates, obtained from 51 hospitals across the country between 2010 and 2011. Of the 32 PFGE genotypes of environmental isolates, 8 genotypes were identical to those of clinical samples. Serovar Newport isolates with PFGE patterns SNX.119 and SNX.183 obtained from Puzih River samples were also identified in human samples at a local hospital. These suggest that there is a link between environmental and human clinical Salmonella. Identification of Salmonella serovars and genotypes present in surface water provides an indication of the specific S. enterica serovars and genotypes present in humans. This is the first study to investigate the Salmonella serovars and genotypes present in aquatic environment and humans in Taiwan.


Asunto(s)
Ríos/microbiología , Salmonella enterica/aislamiento & purificación , Microbiología del Agua , Electroforesis en Gel de Campo Pulsado , Monitoreo del Ambiente , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Salmonella enterica/genética , Taiwán
15.
Artículo en Inglés | MEDLINE | ID: mdl-28488813

RESUMEN

Imaging mass spectrometry (IMS) allows the study of the spatial distribution of small molecules in biological samples. IMS is able to identify and quantify chemicals in situ from whole tissue sections to single cells. Both vacuum mass spectrometry (MS) and ambient MS systems have advanced considerably over the last decade; however, some limitations are still hard to surmount. Sample pretreatment, matrix or solvent choices, and instrument improvement are the key factors that determine the successful application of IMS to different samples and analytes. IMS with innovative MS analyzers, powerful MS spectrum databases, and analysis tools can efficiently dereplicate, identify, and quantify natural products. Moreover, multimodal imaging systems and multiple MS-based systems provide additional structural, chemical, and morphological information and are applied as complementary tools to explore new fields. IMS has been applied to reveal interactions between living organisms at molecular level. Recently, IMS has helped solve many previously unidentifiable relations between bacteria, fungi, plants, animals, and insects. Other significant interactions on the chemical level can also be resolved using expanding IMS techniques. WIREs Syst Biol Med 2017, 9:e1387. doi: 10.1002/wsbm.1387 For further resources related to this article, please visit the WIREs website.


Asunto(s)
Espectrometría de Masas/tendencias , Imagen Molecular/métodos , Imagen Molecular/tendencias , Animales , Humanos , Espectrometría de Masas/instrumentación , Imagen Molecular/instrumentación
16.
Sci Total Environ ; 581-582: 378-385, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28043703

RESUMEN

Multilocus sequence typing (MLST) is an approach for prediction of Salmonella servoar and eBRUST groups (eBGs) based on seven typing scheme of housekeeping genes. Up to date, >220.000 allelic profiles and 65,973 Salmonella strains have been established in the MLST database. Several studies have modified MLST method with fewer targeted housekeeping genes for the purpose of economy and efficiency. Nevertheless, no study has conducted systematically to evaluate the correlation between the numbers of housekeeping genes targeted and the accuracy of prediction rate. In this study, we aimed to tackle this problem by extracting data from the MLST database as a whole using the software RStudio. Our results indicated that as the numbers of genes in MLST scheme increased, the accuracy of the eBGs prediction rate increased and reached 100% when the gene numbers are greater than or equal to 5. To examine the applicability of the approach, 395 environmental water samples were subjected to this study. A set of 52 Salmonella enterica isolates was initially used to develop MLST targeting seven housekeeping genes. A total of 29 sequence types, including 11 new sequence types were found among the 52 sequenced isolates that differentiated into 19 serotypes. Moreover, two novel sequence types did not belong to current classification. Our results show that the outcome in the three-gene sequence typing (aroC, hisD, and purE) was as accurate as in the seven-gene sequence typing for prediction of environmental Salmonella isolates. Our data suggested that this five-gene and reduced gene-number sequence-typing scheme can serve as an alternative modified MLST when effectiveness and financial management were the concerns.


Asunto(s)
Monitoreo del Ambiente , Tipificación de Secuencias Multilocus , Salmonella enterica/clasificación , Microbiología del Agua , Técnicas de Tipificación Bacteriana , Genes Bacterianos , Filogenia , Salmonella enterica/genética , Análisis de Secuencia de ADN
17.
Water Sci Technol ; 73(8): 1832-41, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27120637

RESUMEN

Human adenovirus (HAdV) infections can occur throughout the year. Cases of HAdV-associated respiratory disease have been more common in the late winter, spring, and early summer. In this study, to provide viral pollution data for further epidemiological studies and governmental actions, the presence of HAdV in the aquatic environment was quantitatively surveyed in the summer. This study was conducted to compare the efficiencies of nested-PCR (polymerase chain reaction) and qPCR (quantitative PCR) for detecting HAdV in environmental waters. A total of 73 water samples were collected from Puzi River in Taiwan and subjected to virus concentration methods. In the results, qPCR had much better efficiency for specifying the pathogen in river sample. HAdV41 was detected most frequently in the river water sample (10.9%). The estimated HAdV concentrations ranged between 6.75 × 10(2) and 2.04 × 10(9) genome copies/L. Significant difference was also found in heterotrophic plate counts, conductivity, water temperature, and water turbidity between presence/absence of HAdV. HAdV in the Puzi River may pose a significant health risk.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Ríos/virología , Microbiología del Agua , Humanos , Taiwán
18.
Ecotoxicol Environ Saf ; 124: 37-41, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26454073

RESUMEN

Diarrheagenic Escherichia coli (DEC) are the most common agents of diarrhea. Waterborne DEC could pose a potential health risk to human through agricultural, household, recreational, and industrial use. There are few published reports on the detection of DEC and its seasonal distribution in aquatic environments. The presence of DEC in different types of aquatic environments was investigated in this study. Water samples were collected from major rivers, water reservoirs, and recreational hot springs throughout Taiwan. Moreover, an intensive water sampling plan was carried out along Puzih River. The detection of DEC target genes was used to determine the presence of enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), and Shiga toxin-producing E. coli (STEC). Among the 383 water samples analyzed, DEC was found in 122 (31.8%) samples. The detection rate varied by genotype, raging from 3.6% for STEC to 17.2% for EPEC. The DEC detection rate was higher from river waters than reservoirs and hot springs. In addition, DEC was detected at a higher rate in spring and summer. The presence of EPEC was significantly associated with total coliform levels among hot spring samples. Moreover, the presence of ETEC in river water samples was associated with heterotrophic plate counts. Water with EPEC differed significantly in pH from Puzih River samples. These results suggest that seasonal characteristics may affect the presence of DEC in different aquatic environments, and water quality indicators may be indicative of the presence of DEC.


Asunto(s)
Escherichia coli Enteropatógena/aislamiento & purificación , Escherichia coli Enterotoxigénica/aislamiento & purificación , Manantiales de Aguas Termales/microbiología , Ríos/microbiología , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Abastecimiento de Agua , Diarrea , Infecciones por Escherichia coli , Humanos , Estaciones del Año , Taiwán
19.
Environ Sci Pollut Res Int ; 23(3): 2928-36, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26490890

RESUMEN

In this study, the seasonal difference and the observable presence/absence of human adenovirus (HAdV) in the Puzih River basin in Taiwan was investigated. A total of 288 water samples were collected from 24 sites from March 2014 to February 2015. Human AdV analysis of sample was subjected to viral concentration using a GN-6 Metricel® filter, followed by DNA extraction, nested-PCR, and qPCR. Human AdV was detected in 34.3 % (99/288) of the entire river water sample. A higher percentage of HAdV (76.4 %) was obtained during the winter. The HAdV median concentration was relatively high in fall (1.4 × 10(3) copies/L) and winter (2.8 × 10(3) copies/L). Significant difference and correlation were found between the seasonal variation of HAdV and water quality parameters, including heterotrophic plate count, total coliform, water temperature, and turbidity. The most frequently identified HAdV (subgenus F) serotype was 41. Human AdV-41 is the main cause of gastroenteritis and should be considered for associated human health risk potential in the Puzih River basin.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Agua Dulce/virología , Ríos/virología , Estaciones del Año , Taiwán , Clima Tropical
20.
Genome Announc ; 3(6)2015 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-26564046

RESUMEN

An endophytic bacterium, Burkholderia cenocepacia 869T2, isolated from vetiver grass, has shown its abilities for both in planta biocontrol and plant growth promotion. Its draft genome sequence was determined to provide insights into those metabolic pathways involved in plant-beneficial activity. This is the first genome report for endophytic B. cenocepacia.

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