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1.
Even if many Vibrio spp. are endemic to coastal waters, their distribution in northern temperate and boreal waters is poorly studied. To identify environmental factors regulating Vibrio populations in a salinity gradient along the Swedish coastline, we combined Vibrio-specific quantitative competitive PCR with denaturant gradient gel electrophoresis-based genotyping. The total Vibrio abundance ranged from 4 × 103 to 9.6 × 104 cells liter−1, with the highest abundances in the more saline waters of the Skagerrak Sea. Several Vibrio populations were present throughout the salinity gradient, with abundances of single populations ranging from 5 × 102 to 7 × 104 cells liter−1. Clear differences were observed along the salinity gradient, where three populations dominated the more saline waters of the Skagerrak Sea and two populations containing mainly representatives of V. anguillarum and V. aestuarianus genotypes were abundant in the brackish waters of the Baltic Sea. Our results suggest that this apparent niche separation within the genus Vibrio may also be influenced by alternate factors such as nutrient levels and high abundances of dinoflagellates. A V. cholerae/V. mimicus population was detected in more than 50% of the samples, with abundances exceeding 103 cells liter−1, even in the cold (annual average water temperature of around 5°C) and low-salinity (2 to 4‰) samples from the Bothnian Bay (latitude, 65°N). The unsuspected and widespread occurrence of this population in temperate and boreal coastal waters suggests that potential Vibrio pathogens may also be endemic to cold and brackish waters and hence may represent a previously overlooked health hazard.  相似文献   

2.
An assay has been developed for measuring protein biomass of marine planktonic bacteria by flow cytometry. The method was calibrated by using five species of Bacteria (an Arcobacter sp., a Cytophaga sp., an Oceanospirillum sp., a Pseudoalteromonas sp., and a Vibrio sp.) recently isolated from seawater samples and grown in culture at different temperatures. The intensity of SYPRO-protein fluorescence of these bacteria strongly correlated with their total protein content, measured by the bicinchoninic acid method to be in the range of 60 to 330 fg of protein cell−1 (r2 = 0.93, n = 34). According to the calibration, the mean biomass of planktonic bacteria from the North Sea in August 1998 was 24 fg of protein cell−1.  相似文献   

3.
The relative abundance of bacteria in the mucus and crushed tissue of the Mediterranean coral Oculina patagonica was determined by analyses of the 16S rRNA genes of isolated colonies and from a 16S rRNA clone library of extracted DNA. By SYBR gold staining, the numbers of bacteria in mucus and tissue samples were 6.2 × 107 and 8.3 × 108/cm2 of coral surface, respectively, 99.8% of which failed to produce colonies on Marine Agar. From analysis of mucus DNA, the most-abundant bacterium was Vibrio splendidus, representing 68% and 50% of the clones from the winter and summer, respectively. After removal of mucus from coral by centrifugation, analyses of DNA from the crushed tissue revealed a large diversity of bacteria, with Vibrio species representing less than 5% of the clones. The most-abundant culturable bacteria were a Pseudomonas sp. (8 to 14%) and two different α-proteobacteria (6 to 18%). Out of a total 1,088 16S rRNA genes sequenced, 400 different operational taxonomic units were identified (>99.5% identity). Of these, 295 were novel (<99% identical to any sequences in the GenBank database). This study provides a comprehensive database for future examinations of changes in the bacterial community during bleaching events.  相似文献   

4.
Blastocystis species has been extensively studied in recent few years to establish its pathogenecity. Present study was designed to identify and examine the association of Blastocystis sp. and its subtypes with Irritable Bowel Syndrome (IBS).Blastocystis sp. detected using wet-mount microscopy, trichrome staining, in-vitro culture and Polymerase Chain Reaction (PCR) assay in a cohort of IBS patients (n = 150) and healthy controls (n = 100). Isolates of Blastocystis sp.were subtyped using Sequence Tagged Site and representative samples were sequenced at SSUrRNA locus.A total of sixty five isolates of Blastocystis sp. were identified [IBS (n = 50); Controls (n = 15)] of which 91% belonged to ST3 and 9% belonged to ST1. No other subtypes could be identified. Statistically significant association was observed between Blastocystis sp. and IBS patients; however no particular subtype could be ascertained to any particular clinical type of IBS.The frequency of occurrence of Blastocystis sp. was more in IBS patients as compared to the controls and ST3 being the most prevalent subtype. The genetic polymorphism of SSU-rRNA gene amongst the different Blastocystis sp.isolates found in this study reinforces the fact that these organisms are genetically highly divergent.  相似文献   

5.
Vibrio species are an abundant and diverse group of bacteria that form associations with phytoplankton. Correlations between Vibrio and phytoplankton abundance have been noted, suggesting that growth is enhanced during algal blooms or that association with phytoplankton provides a refuge from predation. Here, we investigated relationships between particle-associated Vibrio spp. and phytoplankton in Delaware''s inland bays (DIB). The relative abundances of particle-associated Vibrio spp. and algal classes that form blooms in DIB (dinoflagellates, diatoms, and raphidophytes) were determined using quantitative PCR. The results demonstrated a significant correlation between particle-associated Vibrio abundance and phytoplankton, with higher correlations to diatoms and raphidophytes than to dinoflagellates. Species-specific associations were examined during a mixed bloom of Heterosigma akashiwo and Fibrocapsa japonica (Raphidophyceae) and indicated a significant positive correlation for particle-associated Vibrio abundance with H. akashiwo but a negative correlation with F. japonica. Changes in Vibrio assemblages during the bloom were evaluated using automated ribosomal intergenic spacer analysis (ARISA), which revealed significant differences between each size fraction but no significant change in Vibrio assemblages over the course of the bloom. Microzooplankton grazing experiments showed that losses of particle-associated Vibrio spp. may be offset by increased growth in the Vibrio population. Moreover, analysis of Vibrio assemblages by ARISA also indicated an increase in the relative abundance for specific members of the Vibrio community despite higher grazing pressure on the particle-associated population as a whole. The results of this investigation demonstrate links between phytoplankton and Vibrio that may lead to predictions of potential health risks and inform future management practices in this region.  相似文献   

6.
Sequencing and analyses of 16S rRNA gene amplicons were performed to estimate the composition of the rumen methanogen community in 252 samples from eight cohorts of sheep and cattle, separated into 16 different sample groups by diet, and to determine which methanogens are most prominent in the rumens of farmed New Zealand ruminants. Methanobacteriales (relative abundance ± standard deviation, 89.6% ± 9.8%) and Methanomassiliicoccales (10.4% ± 9.8%) were the two major orders and contributed 99.98% (±0.1%) to the rumen methanogen communities in the samples. Sequences from Methanobacteriales were almost entirely from only four different species (or clades of very closely related species). Each was detectable in at least 89% of the samples. These four species or clades were the Methanobrevibacter gottschalkii clade and Methanobrevibacter ruminantium clade with a mean abundance of 42.4% (±19.5% standard deviation) and 32.9% (±18.8%), respectively, and Methanosphaera sp. ISO3-F5 (8.2% ± 6.7%) and Methanosphaera sp. group5 (5.6% ± 5.7%). These four species or clades appeared to be primarily represented by only one or, in one case, two dominant sequence types per species or clade when the sequences were grouped into operational taxonomic units (OTUs) at 99% sequence identity. The mean relative abundance of Methanomassiliicoccales in the samples was relatively low but exceeded 40% in some of the treatment groups. Animal feed affected the apparent methanogen community structure of both orders, as evident from differences in relative abundances of the major OTUs in animals under different feeding regimens.  相似文献   

7.
IntroductionThe clinical significance of Blastocystis sp. and Dientamoeba fragilis in patients with gastrointestinal symptoms is a controversial issue. Since the pathogenicity of these protists has not been fully elucidated, testing for these organisms is not routinely pursued by most laboratories and clinicians. Thus, the prevalence of these organisms and the subtypes of Blastocystis sp. in human patients in Turkey are not well characterized. This study aimed to determine the prevalence of Blastocystis sp. and D. fragilis in the diarrheic stool samples of immunodeficient and immunocompetent patients using conventional and molecular methods and to identify Blastocystis sp. subtypes using next generation sequencing.Material and methodsIndividual stool specimens were collected from 245 immunodeficient and 193 immunocompetent diarrheic patients between March 2017 and December 2019 at the Gazi University Training and Research Hospital in Ankara, Turkey. Samples were screened for Blastocystis sp. and D. fragilis by conventional and molecular methods. Molecular detection of both protists was achieved by separate qPCRs targeting a partial fragment of the SSU rRNA gene. Next generation sequencing was used to identify Blastocystis sp. subtypes.ResultsThe prevalence of Blastocystis sp. and D. fragilis was 16.7% and 11.9%, respectively as measured by qPCR. The prevalence of Blastocystis sp. and D. fragilis was lower in immunodeficient patients (12.7% and 10.6%, respectively) compared to immunocompetent patients (21.8% and 13.5%, respectively). Five Blastocystis sp. subtypes were identified and the following subtype distribution was observed: ST3 54.4% (n = 37), ST2 16.2% (n = 11), ST1 4.4% (n = 3), ST6 2.9% (n = 2), ST4 1.5% (n = 1), ST2/ST3 11.8% (n = 8) and ST1/ST3 8.8% (n = 6). There was no statistically significant difference in the distribution of Blastocystis sp. subtypes between immunocompetent and immunodeficient patients.Conclusion and recommendationOur findings demonstrated that Blastocystis sp. and D. fragilis are commonly present in immunocompetent and immunodeficient patients with diarrhea. This study is the first to use next generation sequencing to address the presence of Blastocystis sp. mixed subtypes and intra-subtype variability in clinical samples in Turkey.  相似文献   

8.
Bacteria from the genus Vibrio are a common and environmentally important group of bacteria within coastal environments and include species pathogenic to aquaculture organisms. Their distribution and abundance are linked to specific environmental parameters, including temperature, salinity and nutrient enrichment. Accurate and efficient detection of Vibrios in environmental samples provides a potential important indicator of overall ecosystem health while also allowing rapid management responses for species pathogenic to humans or species implicated in disease of economically important aquacultured fish and invertebrates. In this study, we developed a surface immuno-functionalisation protocol, based on an avidin-biotin type covalent binding strategy, allowing specific sandwich-type detection of bacteria from the Vibrio genus. The assay was optimized on 12 diverse Vibrio strains, including species that have implications for aquaculture industries, reaching detection limits between 7×103 to 3×104 cells mL−1. Current techniques for the detection of total Vibrios rely on laborious or inefficient analyses resulting in delayed management decisions. This work represents a novel approach for a rapid, accurate, sensitive and robust tool for quantifying Vibrios directly in industrial systems and in the environment, thereby facilitating rapid management responses.  相似文献   

9.
A vibrio-like bacterium, designated Vibrio sp. (BML 79-078), was isolated from moribund juvenile Amercan lobsters, Homarus americanus. This is the first report of a vibrio-like bacterium being associated with a disease of lobsters. Koch's postulates have been satisfied for this bacterium. In this study, Vibrio sp. (BML 79-078) and Vibrio anguillarum (ATCC 19264) were found to be pathogenic when injected into juvenile lobsters held at 20°C, while Enterobacter aerogenes was not. An endotoxin was found to be associated with the pathogenesis of the disease syndrome caused by Vibrio sp. (BML 79-087).  相似文献   

10.
Vibrios in the Louisiana gulf coast environment   总被引:3,自引:0,他引:3  
Roberts  N. C.  Siebeling  R. J.  Kaper  J. B.  Bradford  H. B. 《Microbial ecology》1982,8(4):299-312
A polyphasic approach, using bacteriological, immunological, and molecular biological techniques was used to elucidate the distribution of pathogenicVibrio species in the Louisiana coastal environment. A variety ofVibrio species pathogenic for man, includingV. cholerae, V. parahaemolyticus, V. fluvialis, andV. vulnificus, were found to be ubiquitous in Louisiana.Vibrio species monitored were shown to fluctuate in response to environmental factors of temperature, salinity, and nutrient level, and to vary independently of fecal coliform counts. A comprehensive serological screening system, based on species specific H antigens, was developed to identify pathogenicVibrio sp. 1 step after primary isolation.Vibrio sp. were correctly identified with accuracies ranging from 93–100%, depending on the specific H antiserum. Over 2,500V. cholerae isolates were rapidly screened for production of cholera toxin by DNA hybridization of specific toxin gene probes to colonies inoculated on nitrocellulose filter paper. The toxin gene probes, together with O antigen analysis, revealed that enterotoxigenicV. cholerae 01 serovars were recovered only from sewage stations or human disease, whereas enterotoxigenicV. cholerae non 01 serovars were recovered from environmental samples in addition to clinical and sewage samples. The results of this study indicate that techniques of immunology and molecular biology are very valuable supplements to conventional bacteriological techniques in studying the epidemiology and ecology of pathogenicVibrio sp.  相似文献   

11.
Myocardial infarction (MI) is divided into either ST elevation MI (STEMI) or non-ST elevation MI (NSTEMI), differing in a number of clinical characteristics. We sought to identify genetic variants conferring risk to NSTEMI or STEMI by conducting a genome-wide association study (GWAS) of MI stratified into NSTEMI and STEMI in a consecutive sample of 1,579 acute MI cases with 1,576 controls. Subsequently, we followed the results in an independent population-based sample of 562 cases and 566 controls, a partially independent prospective cohort (N = 16,627 with 163 incident NSTEMI cases), and examined the effect of disease-associated variants on gene expression in 513 healthy participants. Genetic variants on chromosome 1p13.3 near the damage-regulated autophagy modulator 2 gene DRAM2 associated with NSTEMI (rs656843; odds ratio 1.57, P = 3.11 × 10−10) in the case-control analysis with a consistent but not statistically significant effect in the prospective cohort (rs656843; hazard ratio 1.13, P = 0.43). These variants were not associated with STEMI (rs656843; odds ratio, 1.11, P = 0.20; hazard ratio 0.97, P = 0.87), appearing to have a pronounced effect on NSTEMI risk. A majority of the variants at 1p13.3 associated with NSTEMI were also associated with the expression level of DRAM2 in blood leukocytes of healthy controls (top-ranked variant rs325927, P = 1.50 × 10−12). The results suggest that genetic factors may in part influence whether coronary artery disease results in NSTEMI rather than STEMI.  相似文献   

12.
Diarrheal disease remains an unsolved problem in developing countries. The emergence of new etiological agents (non-cholera vibrios) is a major cause of concern for health planners. We attempted to unveil the seasonal dynamics of entero-pathogenic Vibrios in Gangetic riverine-estuarine ecosystem. 120 surface water samples were collected for a period of one year from 3 sampling sites on the Hooghly river. Five enteropathogenic Vibrio species, V. cholerae (35%), V. parahaemolyticus (22.5%), V. mimicus (19.1%), V. alginolyticus (15.8%) and V. vulnificus (11.6%), were present in the water samples. The vibriophages, V. vulnificus ɸ (17.5%), V. alginolyticus ɸ (17.5%), V. parahaemolyticus ɸ (10%), V. cholerae non-O1/O139 ɸ (26.6%) and V. mimicus ɸ (9.1%), were also detected in these samples. The highest number of Vibrios were noted in the monsoon (20–34°C), and to a lesser extent, in the summer (24–36°C) seasons. Samples positive for phages for any of the identified Vibrio species were mostly devoid of that particular bacterial organism and vice versa. The detection of toxin genes and resistance to β-lactam antibiotics in some environmental enteropathogenic Vibrio species in the aquatic niches is a significant outcome. This finding is instrumental in the south Bengal diarrhoeal incidence.  相似文献   

13.

Objective

We attempted to determine whether the level of enzymes sialyltransferase (ST) and neuraminidase (Neu) and sialic acid (SIA) in patients with systemic lupus erythematosus (SLE) correlates with the SLE Disease Activity Index (SLEDAI) and in patients with rheumatoid arthritis (RA) correlates with the Disease Activity Score28 (DAS28).

Methods

We examined cell-surface levels of ST6Gal-1, Neu1, ST3Gal-1, Neu3, α-2,6-SIA, and α-2,3-SIA by using fluorescent anti-enzyme antibodies, fluorescent-conjugated Sambucus nigra lectin, and fluorescent-conjugated Maackia amurensis lectin on blood cells in SLE and RA patients and assessed correlations of these levels with SLEDAI and with DAS28. Areas under the curve (AUC) were calculated for different variables against SLEDAI.

Results

The B-cell ST3Gal-1/Neu3 ratio positively correlated with SLEDAI scores (ρ = 0.409 and P = 0.002, statistically significant after Bonferroni’ correction for multiple analyses.). It was supported by the inverse correlation of B-cell Neu3 levels with SLEDAI scores (ρ = −0.264, P = 0.048). The B-cell ST3Gal-1/Neu3 ratio against SLEDAI yielded an AUC of 0.689, which was comparable to that of anti-dsDNA levels at 0.635. In contrast, both ST3Gal-1 and Neu3 levels of RA B cells (r = 0.376, P = 0.013; r = 0.425, P = 0.005, respectively) correlated positively with high disease-activity DAS28 scores.

Conclusion

B-cell ST3Gal-1/Neu3 ratios in SLE and B-cell ST3Gal-1 and Neu3 levels in RA with high disease-activity DAS28 scores correlated with disease activity measures and may be useful in monitoring disease activities.  相似文献   

14.

Background

This study was aimed at investigating the functional significance of heparan sulfate (glucosamine) 3-O-sulfotransferase 2 (HS3ST2) hypermethylation in non-small cell lung cancer (NSCLC).

Methodology/ Principal Findings

HS3ST2 hypermethylation was characterized in six lung cancer cell lines, and its clinical significance was analyzed using 298 formalin-fixed paraffin-embedded tissues and 26 fresh-frozen tissues from 324 NSCLC patients. MS-HRM (methylation-specific high-resolution melting) and EpiTYPERTM assays showed substantial hypermethylation of CpG island at the promoter region of HS3ST2 in six lung cancer cell lines. The silenced gene was demethylated and re-expressed by treatment with 5-aza-2′-deoxycytidine (5-Aza-dC). A promoter assay also showed the core promoter activity of HS3ST2 was regulated by methylation. Exogenous expression of HS3ST2 in lung cancer cells H460 and H23 inhibited cell migration, invasion, cell proliferation and whereas knockdown of HS3ST2 in NHBE cells induced cell migration, invasion, and cell proliferation in vitro. A negative correlation was observed between mRNA and methylation levels of HS3ST2 in 26 fresh-frozen tumors tissues (ρ = -0.51, P = 0.009; Spearman’s rank correlation). HS3ST2 hypermethylation was found in 95 (32%) of 298 primary NSCLCs. Patients with HS3ST2 hypermethylation in 193 node-negative stage I-II NSCLCs with a median follow-up period of 5.8 years had poor overall survival (hazard ratio = 2.12, 95% confidence interval = 1.25–3.58, P = 0.005) compared to those without HS3ST2 hypermethylation, after adjusting for age, sex, tumor size, adjuvant therapy, recurrence, and differentiation.

Conclusions/ Significance

The present study suggests that HS3ST2 hypermethylation may be an independent prognostic indicator for overall survival in node-negative stage I-II NSCLC.  相似文献   

15.
The β-agarase C gene (agaC) of a marine bacterium, Vibrio sp. strain PO-303, consisted of 1,437 bp encoding 478 amino acid residues. β-Agarase C was identified as the first β-agarase that cannot hydrolyze neoagarooctaose and smaller neoagarooligosaccharides and was assigned to a novel glycoside hydrolase family.  相似文献   

16.
17.
We revise the 10 genera and 23 species of the tribe Phaeogenini (Ichneumonidae: Ichneumoninae) known to occur in the Afrotropical region. We describe the following 13 new taxa: Kibalus Rousse, van Noort & Diller, gen. n.; K. toro Rousse, van Noort & Diller, sp. n.; K. mubfs Rousse & van Noort, sp. n.; Arearia oxymoron Rousse & van Noort, sp. n.; Chauvinia nyanga Rousse & van Noort, sp. n.; Dicaelotus asantesana Rousse & van Noort, sp. n.; D. hoerikwaggoensis Rousse & van Noort, sp. n.; D. tablemountainensis Rousse & van Noort, sp. n.; Heterischnus mfongosi Rousse & van Noort, sp. n.; H. mkomazi Rousse & van Noort, sp. n.; Lusius flummox Rousse & van Noort, sp. n.; Tycherus amatola Rousse & van Noort, sp. n.; and T. nardousberg Rousse & van Noort, sp. n. New distribution records: Heterischnus africanus (Heinrich, 1936) from South Africa, Tanzania and Uganda; H. krausi Schönitzer, 1999 from Rwanda; Lusius tenuissimus (Heinrich, 1938) from Democratic Republic of Congo, Malawi, Nigeria, South Africa, and Zimbabwe. A doubtful record of Aethecerus foveolatus Gregor, 1940 from Sao Tome is additionaly reported in the appendix. We provide illustrated diagnoses and identification notes. Online interactive dichotomous and matrix Lucid keys to genera and species are available at http://www.waspweb.org.  相似文献   

18.
Vibrio sp. V26 isolated from mangrove sediment showed 98 % similarity to 16S rRNA gene of Vibrio cholerae, V. mimicus, V. albensis and uncultured clones of Vibrio. Phenotypically also it resembled both V. cholerae and V. mimicus. Serogrouping, virulence associated gene profiling, hydrophobicity, and adherence pattern clearly pointed towards the non—toxigenic nature of Vibrio sp. V26. Purification and characterization of the enzyme revealed that it was moderately thermoactive, nonhemagglutinating alkaline metalloprotease with a molecular mass of 32 kDa. The application of alkaline protease from Vibrio sp. V26 (APV26) in sub culturing cell lines (HEp-2, HeLa and RTG-2) and dissociation of animal tissue (chick embryo) for primary cell culture were investigated. The time required for dissociation of cells as well as the viable cell yield obtained by while administering APV26 and trypsin were compared. Investigations revealed that the alkaline protease of Vibrio sp. V26 has the potential to be used in animal cell culture for subculturing cell lines and dissociation of animal tissue for the development of primary cell cultures, which has not been reported earlier among metalloproteases of Vibrios.  相似文献   

19.
Blastocystis is a common enteric protist that inhabits the gastrointestinal tract of approximately 1 billion people worldwide. In this study, a total of 1,070 patients from two hospitals in Zhengzhou, Central China were enrolled to know molecular characteristics of Blastocystis sp. The microorganism was identified and subtyped with a PCR amplification and sequencing of the small subunit ribosomal deoxyribonucleic acid (SSU-rDNA). The overall minimum prevalence of Blastocystis sp. in participants was 3.1% (33/1070). Although there were no significant differences on Blastocystis sp. infections among study sites, age groups, and gender, the higher infection was observed in the patients with gastrointestinal diseases (8.8%, 15/170). Sequence analysis of the 33 isolates revealed three known subtypes, such as ST1 (n = 7), ST3 (n = 23), and ST7 (n = 3). Among them, ST3 was the dominant subtype being detected in 23 isolates (69.7%), followed by ST1 (21.2%, 7/33) and ST7 (9.1%, 3/33). The phylogenetic analysis demonstrated that three subtypes (ST1, ST3 and ST7) were clustered with their reference sequences with good bootstrap support. The subtype determination of Blastocystis sp. isolates by the phylogenetic analysis was well supported by online platform. The present study provides the first molecular report of Blastocystis sp. infections in hospital patients in Central China.  相似文献   

20.
Pyranone derivative I was isolated from fermented broth of isolated marine bacterial strain Vibrio sp. SKMARSP9. The compound I was characterized, and evaluated for its antimicrobial properties. The isolated strain was identified based on 16S rRNA based phylogenetic analysis. The molecular analysis data suggested that this strain is closely related to Vibrio ruber, Vibrio sp. MSSRF10 and Vibrio rhizosphaerae. The best fermentative growth of this isolate was achieved under halophilic conditions and grew efficiently at 30 °C in the presence of 12 % NaCl. The compound I production by this strain is associated with growth. The unpurified extract is hydrophobic in nature, and released only during late growth phase. The extract was purified and characterized by spectral data using NMR, DEPT, and ESI–MS. The purity of I was 97 % which was confirmed by HPLC. The pyranone derivative I exhibited >50 % antioxidant activity and broad spectrum antimicrobial properties against gram negative and gram positive strains. Molecular docking analysis revealed that this pyranone derivative I may be a potential candidate at pharmaceutical sector.

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-015-0521-0) contains supplementary material, which is available to authorized users.  相似文献   

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