Genomic characteristics and comparative genomics analyses of non-rhizobial endophytic bacteria isolated from legumes.

In addition to typical nitrogen-fixing endosymbionts, legumes harbour other endophytic bacteria within their tissues that may also contribute to plant growth and health (Hardoim et al. 2015). Our previous works revealed that endophytic bacteria isolated from legumes not only have plant growth-promoting traits but are also well adapted to common constraints present in soils of the Mediterranean region (Brígido et al. 2019ab). In this work, we intend to further characterize these endophytic bacteria through genomic and comparative genomic analyses to potentiate their applications in agriculture, providing opportunities for sustainable plant health and food security. Twelve endophytic bacterial isolates were selected based on their potential for plant growth promotion and/or biocontrol of phytopathogens. Based on the 16S rRNA gene sequence analysis, the isolates were assigned to the genera Pseudomonas, Kosakonia, Stenotrophomonas, Serratia, Bacillus and Agrobacterium. Nevertheless, in silico DNA-DNA hybridization analyses revealed that 3 strains represent novel species distinct from their closest relatives. Their genome sizes ranged from 4.4 M to 7.1 M with a GC content varying from 35.41 to 66.4%. Orthologous gene clusters analysis revealed 9346 clusters and 345 single-copy gene clusters, albeit only 499 gene clusters (comprising 6110 proteins) were shared among all strains. Whole genome sequence analysis revealed genes potentially associated with attachment and plant colonization, growth promotion and stress protection as well as antifungal activity. In detail, sets of genes for twitching motility, chemotaxis, flagella biosynthesis, and ability to form biofilms (which are related with host plant colonization) were found in their genomes. Presence of genes associated to nitrogen fixation, auxin biosynthesis, siderophore production or phosphorous assimilation reveals their potential as plant growth promoters. Furthermore, genes required for biosynthesis of pyoluteorin, 2,4-diacetylphloroglucinol and pyrrolnitrin underline bacterial biocontrol potential against phytopathogens. Genes related to the production of different molecules and enzymes mediating stress tolerance suggest their ability to rapidly adapt to stressful conditions. Overall, our data provide a better understanding of these endophytic bacteria abilities and further comparative genomic analysis provided insight into the genomic basis of their endophytic lifestyle, plant growth promotion and antifungal activity

Molecular evidence for the occurrence of a new sibling species within the Anopheles (Kerteszia) cruzii complex in south-east Brazil

<p>Abstract</p> <p>Background</p> <p><it>Anopheles cruzii </it>(Diptera: Culicidae) has long been known as a vector of human and simian malaria parasites in southern and south-eastern Brazil. Previous studies have provided evidence that <it>An. cruzii </it>is a species complex, but the status of the different populations and the number of sibling species remains unclear. A recent analysis of the genetic differentiation of the <it>timeless </it>gene among <it>An. cruzii </it>populations from south and south-east Brazil has suggested that the population from Itatiaia, Rio de Janeiro State (south-east Brazil), is in a process of incipient speciation.</p> <p>Methods</p> <p>A ~180 bp fragment of <it>cpr</it>, a gene encoding the NADPH-cytochrome P450 reductase, an enzyme involved in metabolic insecticide resistance and odorant clearance in insects, was used in this study as a molecular marker to analyse the divergence between five <it>An. cruzii </it>populations from south and south-east Brazil.</p> <p>Results</p> <p>Analysis of the genetic differentiation in the <it>cpr </it>gene revealed very high <it>F_ST</it>values and fixed differences between Itatiaia and the other four populations studied (Florianópolis, Cananéia, Juquitiba and Santa Teresa). In addition, the data also provided preliminary evidence that seems to indicate the occurrence of two sympatric sibling species in Itatiaia.</p> <p>Conclusions</p> <p>Population genetics analysis of <it>An. cruzii </it>samples from different localities using a fragment of the <it>cpr </it>gene suggests that the Itatiaia sample represents at least one new sibling species in this complex.</p

Assessing the molecular divergence between Anopheles (Kerteszia) cruzii populations from Brazil using the timeless gene: further evidence of a species complex

Submitted by Sandra Infurna ([email protected]) on 2019-01-15T13:43:46Z No. of bitstreams: 1 luisaDp_rona_etal_IOC_2009.pdf: 651215 bytes, checksum: 4fc0bfe6cd7738120844230e1013d041 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-01-15T13:52:05Z (GMT) No. of bitstreams: 1 luisaDp_rona_etal_IOC_2009.pdf: 651215 bytes, checksum: 4fc0bfe6cd7738120844230e1013d041 (MD5)Made available in DSpace on 2019-01-15T13:52:05Z (GMT). No. of bitstreams: 1 luisaDp_rona_etal_IOC_2009.pdf: 651215 bytes, checksum: 4fc0bfe6cd7738120844230e1013d041 (MD5) Previous issue date: 2009Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Molecular de Insetos. Rio de Janeiro, RJ. Brasil.Universidade Federal de Santa Catarina. Departamento de Microbiologia, Imunologia e Parasitologia. Florianópolis, SC, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Molecular de Insetos. Rio de Janeiro, RJ. Brasil / Queen Mary University of London. School of Biological and Chemical Sciences. London, UK.Universidade Federal de Santa Catarina. Departamento de Microbiologia, Imunologia e Parasitologia. Florianópolis, SC, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Molecular de Insetos. Rio de Janeiro, RJ. Brasil.Background: Anopheles (Kerteszia) cruzii was the most important vector of human malaria in southern Brazil between 1930–1960. Nowadays it is still considered an important Plasmodium spp. vector in southern and south-eastern Brazil, incriminated for oligosymptomatic malaria. Previous studies based on the analysis of X chromosome banding patterns and inversion frequencies in An. cruzii populations from these areas have suggested the occurrence of three sibling species. In contrast, two genetically distinct groups among An. cruzii populations from south/south-east and north-east Brazil have been revealed by isoenzyme analysis. Therefore, An. cruzii remains unclear

IL-4-secreting CD4+ T cells are crucial to the development of CD8+ T-cell responses against malaria liver stages.

CD4+ T cells are crucial to the development of CD8+ T cell responses against hepatocytes infected with malaria parasites. In the absence of CD4+ T cells, CD8+ T cells initiate a seemingly normal differentiation and proliferation during the first few days after immunization. However, this response fails to develop further and is reduced by more than 90%, compared to that observed in the presence of CD4+ T cells. We report here that interleukin-4 (IL-4) secreted by CD4+ T cells is essential to the full development of this CD8+ T cell response. This is the first demonstration that IL-4 is a mediator of CD4/CD8 cross-talk leading to the development of immunity against an infectious pathogen

A chemical survey of exoplanets with ARIEL

Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT