Search results for "Colonisation"
showing 10 items of 87 documents
Colonization Resistance of the Gut Microbiota against Clostridium difficile
2015
Antibiotics strongly disrupt the human gut microbiota, which in consequence loses its colonization resistance capacity, allowing infection by opportunistic pathogens such as Clostridium difficile. This bacterium is the main cause of antibiotic-associated diarrhea and a current problem in developed countries, since its incidence and severity have increased during the last years. Furthermore, the emergence of antibiotic resistance strains has reduced the efficiency of the standard treatment with antibiotics, leading to a higher rate of relapses. Here, we review recent efforts focused on the impact of antibiotics in the gut microbiome and their relationship with C. difficile colonization, as w…
Investigation of the roles of AgrA and σB regulators in Listeria monocytogenes adaptation to roots and soil
2020
ABSTRACT Little is known about the regulatory mechanisms that ensure the survival of the food-borne bacterial pathogen Listeria monocytogenes in the telluric environment and on roots. Earlier studies have suggested a regulatory overlap between the Agr cell–cell communication system and the general stress response regulator σB. Here, we investigated the contribution of these two systems to root colonisation and survival in sterilised and biotic soil. The ability to colonise the roots of the grass Festuca arundinacea was significantly compromised in the double mutant (∆agrA∆sigB). In sterile soil at 25°C, a significant defect was observed in the double mutant, suggesting some synergy between …
Sex-specific interaction between arbuscular mycorrhizal and dark septate fungi in the dioecious plant Antennaria dioica (Asteraceae).
2012
Male and female plants of dioecious species often differ in their resource demands and this has been linked to secondary sexual dimorphism, including sex-specific interactions with other organisms such as herbivores and pollinators. However, little is known about the interaction between dioecious plants and fungal root endophytes. Plants may be simultaneously colonised by arbuscular mycorrhizal (AM) and dark septate (DS) fungi. While it is well established that AM mutualism involves reciprocal transfer of photosynthates and mineral nutrients between roots of host plants and these fungi, the role of DS fungi remains controversial. Here, we report the temporal and spatial variation in AM and …
Evidences of adaptive traits to rocky substrates undermine paradigm of habitat preference of the Mediterranean seagrass Posidonia oceanica
2015
AbstractPosidonia oceanica meadows are acknowledged as one of the most valuable ecosystems of the Mediterranean Sea. P. oceanica has been historically described as a species typically growing on mobile substrates whose development requires precursor communities. Here we document for the first time the extensive presence of sticky hairs covering P. oceanica seedling roots. Adhesive root hairs allow the seedlings to firmly anchor to rocky substrates with anchorage strength values up to 5.23 N, regardless of the presence of algal cover and to colonise bare rock without the need for precursor assemblages to facilitate settlement. Adhesive root hairs are a morphological trait common on plants li…
L’occupation du premier âge du Fer du Clos de Roque à Saint-Maximin-la-Sainte-Baume (Var)
2016
International audience; L’étude porte sur la céramique non tournée provençale, façonnée par les Gaulois du Midi et présente à Marseille de la fin du VIIe s. à la conquête romaine. La consommation de ces récipients non tournés à Massalia est très différente de celle des sites indigènes qui l’entourent. qui importe et consomme en les intégrant des objets d’une culture différente (urnes, jattes indigènes et ollae étrusques). En effet, à Marseille, ces objets ne représentent pas en eux-mêmes des at-tributs ethniques et leur utilisation se produit seulement dans le cadre d’habitudes alimentaires liées à la cité grecque. La proportion de la vaisselle indigène, au sein de la vaisselle de cuisine, …
Lulwoana sp., a dark septate endophyte (DSE) in roots of Posidonia oceanica (L.) Delile seagrass
2014
Posidonia oceanica is the most common, widespread and important monocotyledon seagrass in the Mediterranean Basin, and hosts a large biodiversity of species, including microorganisms with key roles in the marine environment. In this study, we ascertain the presence of a fungal endophyte in the roots of P. oceanica growing on different substrata (rock, sand and matte) in two Sicilian marine meadows. Staining techniques on root fragments and sections, in combination with microscope observations, were used to visualise the fungal presence and determine the percentage of fungal colonisation (FC) in this tissue. In root fragments, statistical analysis of the FC showed a higher mean in roots anch…
Bioaerosol
2022
Cultural heritage constitutive materials can provide excellent substrates for microbial colonisation, highly influenced by thermo-hygrometric parameters. In cultural heritage-related environments, a detrimental microbial load may be present both on artworks surface and in the aerosol. Confined environments (museums, archives, deposits, caves, hypogea) are characterised by peculiarstructures and different thermo-hygrometric conditions, influencing the development of a wide range of microbial species, able to induce artefact biodeterioration and to release biological particles in the aerosol (spores, cellular debrides, toxins, allergens) potentially dangerous for the human health (visitors/us…
Bioarosol
2022
Cultural heritage constitutive materials can provide excellent substrates for microbial colonisation, highly influenced by thermo-hygrometric parameters. In cultural heritage-related environments, a detrimental microbial load may be present both on artworks surface and in the aerosol. Confined environments (museums, archives, deposits, caves, hypogea) are characterised by peculiar structures and different thermo-hygrometric conditions, influencing the development of a wide range of microbial species, able to induce artefact biodeterioration and to release biological particles in the aerosol (spores, cellular debrides, toxins, allergens) potentially dangerous for the human health (visitors/u…
Architettura costruita e spazio abitato nelle città di nuova fondazione in Italia e Spagna
2020
ARCHITETTURA COSTRUITA E SPAZIO ABITATO NELLE CITTÀ DI NUOVA FONDAZIONE IN ITALIA E SPAGNA N. 35 della rivista IN FOLIO, la rivista scientifica di architettura, design, urbanistica, storia e tecnologia che dal 1994 viene pubblicata grazie all’impegno dei dottori e dei dottorandi di ricerca del Dipartimento di Architettura (D’Arch) dell’Università di Palermo (UNIPA).
Modeling temporal and spatial colony‐site dynamics in a long‐lived seabird
2003
We studied the determinants of colony site dynamics in Audouin's gull, Larus audouinii, breeding in a small archipelago of the western Mediterranean. Data on island occupation were available for a series of 25 years, since first colonization of the archipelago in 1973. Group behavior was studied in relation to the components of dispersal: permanence or abandonment (extinction) on an island previously occupied and permanence or occupation (colonization) of another island. Generalized Linear Mixed Models (GLMMs) were used to identify the relative contribution of each explanatory variable to the probability of colony abandonment. Gulls showed a low probability (3%) of abandoning one of the isl…