66 research outputs found
Prisutnost pijavice Pontobdella muricata (Hirudinea: Piscicolidae) na hrskaviÄnjaÄama u Tirenskom moru (Srednje Sredozemlje)
This paper provides the first report of the leech, Pontobdella muricata (Linnaeus, 1758), in the Tyrrhenian Sea. The leech was found on the brown ray, Raja miraletus (Linnaeus 1758), and on the spotted ray, Raja montagui (Fowler, 1910), caught by trawling during autumn 2014.
Complete sequence of 18S rRNA gene, COI mitochondrial gene and partial sequences of the mitochondrial 12S rRNA gene corroborate the determination based on morphological characteristics.U radu se iznosi prvi nalaz pijavice, Pontobdella muricata (Linnaeus, 1758), u Tirenskom moru. Pijavica je pronaÄena na modropjegoj raĆŸi, Raja miraletus (Linnaeus 1758) i na crnopjegoj raĆŸi, Raja montagui (Fowler, 1910), iz koÄarskih lovina tijekom jeseni 2014. godine. Kompletna sekvenca 18S rRNA gena, COI mitohondrijskog gena i djelomiÄne sekvence mitohondrijskog 12S rRNA gena potvrÄuju odreÄivanje koje se zasniva na temelju morfoloĆĄkih svojstava
Analysis of defence systems and a conjugative IncP-1 plasmid in the marine polyaromatic hydrocarbons-degrading bacterium Cycloclasticus sp. 78-ME
Marine prokaryotes have evolved a broad repertoire of defence systems to protect their genomes from lateral gene transfer including innate or acquired immune systems and infection-induced programmed cell suicide and dormancy. Here we report on the analysis of multiple defence systems present in the genome of the strain Cycloclasticus sp. 78-ME isolated from petroleum deposits of the tanker 'Amoco Milford Haven'. Cycloclasticus are ubiquitous bacteria globally important in polyaromatic hydrocarbons degradation in marine environments. Two 'defence islands' were identified in 78-ME genome: the first harbouring CRISPR-Cas with toxin-antitoxin system, while the second was composed by an array of genes for toxin-antitoxin and restriction-modification proteins. Among all identified spacers of CRISPR-Cas system only seven spacers match sequences of phages and plasmids. Furthermore, a conjugative plasmid p7ME01, which belongs to a new IncP-1Ξ ancestral archetype without any accessory mobile elements was found in 78-ME. Our results provide the context to the co-occurrence of diverse defence mechanisms in the genome of Cycloclasticus sp. 78-ME, which protect the genome of this highly specialized PAH-degrader. This study contributes to the further understanding of complex networks established in petroleum-based microbial communities
Quantitation of HBV cccDNA in anti-HBc-positive liver donors by droplet digital PCR: A new tool to detect occult infection
Background & Aims: The accurate diagnosis of occult hepatitis B virus (HBV) infection (OBI) requires the demonstration of HBV DNA in liver biopsies of hepatitis B surface antigen-negative individuals. However, in clinical practice a latent OBI is deduced by the finding of the antibody to the hepatitis B core antigen (anti-HBc). We investigated the true prevalence of OBI and the molecular features of intrahepatic HBV in anti-HBc-positive individuals.
Methods: The livers of 100 transplant donors (median age 68.2 years; 64 males, 36 females) positive for anti-HBc at standard serologic testing, were examined for total HBV DNA by nested-PCR and for the HBV covalently closed circular DNA (HBV cccDNA) with an in-house droplet digital PCR assay (ddPCR) (Linearity: R2 = 0.9998; lower limit of quantitation and detection of 2.4 and 0.8 copies/105 cells, respectively). Results: A total of 52% (52/100) of the individuals studied were found to have OBI. cccDNA was found in 52% (27/52) of the OBI- positive, with a median 13 copies/105 cells (95% CI 5â25). Using an assay specific for anti-HBc of IgG class, the median antibody level was significantly higher in HBV cccDNA-positive than neg- ative donors (17.0 [7.0â39.2] vs. 5.7 [3.6â9.7] cut-off index [COI], respectively, p = 0.007). By multivariate analysis, an anti-HBc IgG value above 4.4 COI was associated with the find- ing of intrahepatic HBV cccDNA (odds ratio 8.516, p = 0.009); a lower value ruled out its presence with a negative predictive value of 94.6%.
Conclusions: With a new in-house ddPCR-based method, intra- hepatic HBV cccDNA was detectable in quantifiable levels in about half of the OBI cases examined. The titer of anti-HBc IgG may be a useful surrogate to predict the risk of OBI reactiva- tion in immunosuppressed patients
Metabolic and evolutionary patterns in the extremely acidophilic archaeon Ferroplasma acidiphilum YT
Ferroplasmaceae represent ubiquitous iron-oxidising extreme acidophiles with a number of unique physiological traits. In a genome-based study of Ferroplasma acidiphilum YT, the only species of the genus Ferroplasma with a validly published name, we assessed its central metabolism and genome stability during a long-term cultivation experiment. Consistently with physiology, the genome analysis points to F. acidiphilum YT having an obligate peptidolytic oligotrophic lifestyle alongside with anaplerotic carbon assimilation. This narrow trophic specialisation abridges the sugar uptake, although all genes for glycolysis and gluconeogenesis, including bifunctional unidirectional fructose 1,6-bisphosphate aldolase/phosphatase, have been identified. Pyruvate and 2-oxoglutarate dehydrogenases are substituted by âancientâ CoA-dependent pyruvate and alpha-ketoglutarate ferredoxin oxidoreductases. In the lab culture, after ~550 generations, the strain exhibited the mutation rate of â„1.3âĂâ10â8 single nucleotide substitutions per site per generation, which is among the highest values recorded for unicellular organisms. All but one base substitutions were G:C to A:T, their distribution between coding and non-coding regions and synonymous-to-non-synonymous mutation ratios suggest the neutral drift being a prevalent mode in genome evolution in the lab culture. Mutations in nature seem to occur with lower frequencies, as suggested by a remarkable genomic conservation in F. acidiphilum YT variants from geographically distant populations
Ferrous iron- and ammonium-rich diffuse vents support habitat-specific communities in a shallow hydrothermal field off the Basiluzzo Islet (Aeolian Volcanic Archipelago)
Ammonium- and Fe(II)-rich fluid flows, known from deep-sea hydrothermal systems, have been extensively studied in the last decades and are considered as sites with high microbial diversity and activity. Their shallow-submarine counterparts, despite their easier accessibility, have so far been under-investigated, and as a consequence, much less is known about microbial communities inhabiting these ecosystems. A field of shallow expulsion of hydrothermal fluids has been discovered at depths of 170-400 meters off the base of the Basiluzzo Islet (Aeolian Volcanic Archipelago, Southern Tyrrhenian Sea). This area consists predominantly of both actively diffusing and inactive 1-3 meters-high structures in the form of vertical pinnacles, steeples and mounds covered by a thick orange to brown crust deposits hosting rich benthic fauna. Integrated morphological, mineralogical, and geochemical analyses revealed that, above all, these crusts are formed by ferrihydrite-type Fe3+ oxyhydroxides. Two cruises in 2013 allowed us to monitor and sampled this novel ecosystem, certainly interesting in terms of shallow-water iron-rich site. The main objective of this work was to characterize the composition of extant communities of iron microbial mats in relation to the environmental setting and the observed patterns of macrofaunal colonization. We demonstrated that iron-rich deposits contain complex and stratified microbial communities with a high proportion of prokaryotes akin to ammonium- and iron-oxidizing chemoautotrophs, belonging to Thaumarchaeota, Nitrospira, and Zetaproteobacteria. Colonizers of iron-rich mounds, while composed of the common macrobenthic grazers, predators, filter-feeders, and tube-dwellers with no representatives of vent endemic fauna, differed from the surrounding populations. Thus, it is very likely that reduced electron donors (Fe2+ and NH4+) are important energy sources in supporting primary production in microbial mats, which form a habitat-specific trophic base of the whole Basiluzzo hydrothermal ecosystem, including macrobenthic fauna
Microbial community of the deep-sea brine Lake <em>Kryos </em>seawater-brine interface is active below the chaotropicity limit of life as revealed by recovery of mRNA
Within the complex of deep, hypersaline anoxic lakes (DHALs) of the Mediterranean Ridge we identified a new, unexplored DHAL and named it "Lake Kryos" after a nearby depression. This lake is filled with MgCl2-rich, athalassohaline brine (salinity >470 practical salinity units), presumably formed by the dissolution of Messinian bischofite. Compared to the DHAL Discovery, it contains elevated concentrations of kosmotropic sodium and sulfate ions, which are capable of reducing the net chaotropicily of MgCl2-rich solutions. The brine of Lake Kryos may therefore be biologically permissive at MgCl2 concentrations previously considered incompatible with life. We characterized the microbiology of the seawater-Kryos brine interface and managed to recover mRNA from the 2.27-3.03 M MgCl2 layer (equivalent to 0.747-0.631 water-activity) thereby expanding the established chaotropicity window-for-life. The primary bacterial taxa present there were KB1 candidate division and DHAL-specific group of organisms, distantly related to Desulfohalobium. Two euryarchaeal candidate divisions MSBL1 and HC1, detected in minority in the overlaying layers, accounted for more than 85% of the rRNA-containing archaeal clones analyzed in 2.27-3.03 M MgCl2 layer. These findings shed light on the plausibility of life in highly chaotropic environments, geochemical windows for microbial extremophiles, and have implications for habitability elsewhere in the Solar System
Bollettino Sismico Italiano: Analisys of Early Aftershocks of the 2016 MW 6.0 Amatrice, MW 5.9 Visso and MW 6.5 Norcia earthquakes in Central Italy
The Amatrice-Visso-Norcia seismic sequence is the most important of the last 30 years in Italy. The seismic sequence started on 24 August, 2016 and still is ongoing in central Apennines. At the end of February 2017 more than 57,000 events were located, 80,000 events up to the end of September 2017 (Fig. 1). The mainshocks of the sequence occurred on 24 August 2016 (Mw 6.0 and Mw 5.4), 26 October 2016 (Mw 5.4 and Mw 5.9), 30 October 2016 (Mw 6.5), 18 January 2017 (four earthquakes Mwâ„ 5.0).
In this seismic sequence, all the waveforms recorded by temporary stations deployed by the SISMIKO emergency group (stations T12**; Moretti et al., 2016) where available in real- time at the surveillance room of INGV. Because of the high level of seismicity and the dense seismic network installed in the region, more than 150 events per day were located at the end of February 2017; still 60 events per day were located up to the end of August 2017.The Amatrice-Visso-Norcia is the most important seismic sequence since 2015, the time when the analysis procedures of the BSI group (Bollettino Sismico Italiano) were revised (Nardi et al., 2015). BSI is now available every four months on the web: bulletins contain revised earthquakes (location and magnitude) with MLâ„ 1.5, quasi-real time revision of MLâ„ 3.5 earthquakes and phase arrivals from waveforms recorded on seismic stations available from the European Integrated Data Archive (EIDA), (Mazza et al., 2012).
These last procedures allow the integration of signals from temporary seismic stations (Moretti et al., 2014) installed by the emergency group SISMIKO (Moretti and Sismiko working group, 2016), even when they are not in real time transmission, if they are rapidly archived in EIDA, together with real time signals from the seismic stations of the permanent INGV network.
The analysis strategy of the BSI group for the Amatrice -Visso - Norcia seismic sequence (AVN.s.s in the following) was to select the earthquakes located in the box with min/max latitude: 42.2/43.2 - and min/max longitude: 12.4/14.1 to prepare a special volume of BSI on the seismic sequence.PublishedTrieste, Italy1SR. TERREMOTI - Servizi e ricerca per la Societ
IL28B, HLA-C, and KIR Variants Additively Predict Response to Therapy in Chronic Hepatitis C Virus Infection in a European Cohort: A Cross-Sectional Study
Vijayaprakash Suppiah and colleagues show that genotyping hepatitis C patients for the IL28B, HLA-C, and KIR genes improves the ability to predict whether or not patients will respond to antiviral treatment
Discovery of anaerobic lithoheterotrophic haloarchaea, ubiquitous in hypersaline habitats
Hypersaline anoxic habitats harbour numerous novel uncultured archaea whose metabolic and ecological roles remain to be elucidated. Until recently, it was believed that energy generation via dissimilatory reduction of sulfur compounds is not functional at salt saturation conditions. Recent discovery of the strictly anaerobic acetotrophic Halanaeroarchaeum compels to change both this assumption and the traditional view on haloarchaea as aerobic heterotrophs. Here we report on isolation and characterization of a novel group of strictly anaerobic lithoheterotrophic haloarchaea, which we propose to classify as a new genus Halodesulfurarchaeum. Members of this previously unknown physiological group are capable of utilising formate or hydrogen as electron donors and elemental sulfur, thiosulfate or dimethylsulfoxide as electron acceptors. Using genome-wide proteomic analysis we have detected the full set of enzymes required for anaerobic respiration and analysed their substrate-specific expression. Such advanced metabolic plasticity and type of respiration, never seen before in haloarchaea, empower the wide distribution of Halodesulfurarchaeum in hypersaline inland lakes, solar salterns, lagoons and deep submarine anoxic brines. The discovery of this novel functional group of sulfur-respiring haloarchaea strengthens the evidence of their possible role in biogeochemical sulfur cycling linked to the terminal anaerobic carbon mineralisation in so far overlooked hypersaline anoxic habitats.</p
Bollettino Sismico Italiano gennaio â aprile 2019
Nel periodo che va dal 1 gennaio al 30 aprile 2019, gli analisti del BSI hanno revisionato tutti gli eventi di magnitudo Mâ„1.5, mentre i parametri dei terremoti di magnitudo inferiore a tale soglia di revisione sono stati calcolati in tempo reale, nella sala di sorveglianza sismica di Roma.Istituto Nazionale di Geofisica e Vulcanologia - Dipartimento di Protezione CivilePublished4IT. Banche dat
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