Genomic diversity of the human pathogen Paracoccidioides across the South American continent

Paracoccidioidomycosis (PCM) is a life-threatening systemic mycosis widely reported in the Gran Chaco ecosystem. The disease is caused by different species from the genus Paracoccidioides, which are all endemic to South and Central America. Here, we sequenced and analyzed 31 isolates of Paracoccidioides across South America, with particular focus on isolates from Argentina and Paraguay. The de novo sequenced isolates were compared with publicly available genomes. Phylogenetics and population genomics revealed that PCM in Argentina and Paraguay is caused by three distinct Paracoccidioides genotypes, P. brasiliensis (S1a and S1b) and P. restrepiensis (PS3). P. brasiliensis S1a isolates from Argentina are frequently associated with chronic forms of the disease. Our results suggest the existence of extensive molecular polymorphism among Paracoccidioides species, and provide a framework to begin to dissect the connection between genotypic differences in the pathogen and the clinical outcomes of the disease.Fil: Teixeira, Marcus de Melo. Universidade do Brasília; BrasilFil: Cattana, Maria Emilia. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Matute, Daniel R.. University of North Carolina; Estados UnidosFil: Muñoz, José F.. Broad Institute Of Mit And Harvard; Estados UnidosFil: Arechavala, Alicia. Hospital Francisco J Muñiz; ArgentinaFil: Isbell, Kristin. University of North Carolina; Estados UnidosFil: Schipper, Rafael. Universidade do Brasília; BrasilFil: Santiso, Gabriela Maria. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Tracogna, Fernanda. Gobierno de la Provincia de Chaco. Hospital Julio Cecilio Perrando.; ArgentinaFil: Sosa, María de los Ángeles. Universidad Nacional del Nordeste. Instituto de Medicina Regional; ArgentinaFil: Cech, Norma. Hospital 4 de Junio; ArgentinaFil: Alvarado, Primavera. Instituto de Biomedicina Dr. Jacinto Convit; VenezuelaFil: Barreto, Laura. Instituto Superior de Formación Docente Salome Ureña; República DominicanaFil: Chacón, Yone. Provincia de Salta. Ministerio de Salud Pública. Hospital del Milagro; ArgentinaFil: Ortellado, Juana. Universidad Nacional de Asunción; ParaguayFil: Lima, Cleoni Mendes de. Universidade Federal de Rondonia; BrasilFil: Chang, Marilene Rodrigues. Universidade Federal do Mato Grosso do Sul; BrasilFil: Niño Vega, Gustavo. Universidad de Guanajuato; MéxicoFil: Yasuda, Maria Aparecida Shikanai. Universidade de Sao Paulo; BrasilFil: Felipe, Maria Sueli Soares. Universidade Catolica de Brasilia; BrasilFil: Negroni, Ricardo. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Cuomo, Christina A.. Broad Institute of MIT And Harvard; Estados UnidosFil: Barker, Bridget. Tgen Northern Arizona University; Estados UnidosFil: Giusiano, Gustavo Emilio. Universidad Nacional del Nordeste. Instituto de Medicina Regional; Argentina. Universidad Nacional del Nordeste. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentin

Cannibalism in Naticidae from the la Meseta Formation (Eocene, Antarctica)

Polinices marambioensis is a naticid gastropod which is the most common constituent in fossil accumulations in the upper section of the Cucullaea I Allomember (Middle Eocene) of the La Meseta Formation in James Ross Basin, Antarctic Peninsula. This species was an important predator of infaunal bivalves and gastropods, including other naticids. The aim of this work was to assess the pattern of predation and cannibalistic behaviour of P. marambioensis. A total of 2648 specimens of P. marambioensis were examined for drill holes, which were assigned to Oichnus paraboloides. Drilling frequency data were measured as a proxy for predation intensity and statistical analyses were performed. Further, the site of each drill hole was established according to the morphological features of the shell on each specimen to assess possible preference of predators for the site of perforation. Results suggest that P. marambioensis is an efficient cannibalistic predator for a specific size range of prey (8-22 mm), and drill holes are distributed preferentially in two specific sectors of their shells. This selective cannibalistic prey behaviour in P. marambioensis affected not only the dynamics of their populations but the ecological structure of the community in which they lived.Fil: Brezina, Soledad Silvana. Universidad Nacional de Río Negro. Sede Alto Valle. Instituto de Investigaciones en Paleobiología y Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cech, Norma Beatriz. Universidad Nacional de Río Negro. Sede Alto Valle. Instituto de Investigaciones en Paleobiología y Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Serralta, D. Martín. Universidad Nacional de La Pampa; ArgentinaFil: Casadio, Silvio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentin

Microhabitat-specific differences on the composition and function of biological soil crust communities

Aims: Biological soil crusts (BSC) are key drivers of ecosystem functioning in drylands. Yet understanding their composition/function relationship is still limited due to the poor knowledge about their variability, particularly in terms of small-scale microhabitat differences. Methods: We investigated how changes in BSC community composition (species identity and cover) affect surrogates of soil functions, such as soil erosion resistance, water dynamics and nutrient cycling, in vegetated mound and intermound microhabitats on a semi-arid shrubland of Argentina. We used a correlative approach to evaluate the composition/function relationship, and we compiled information available in the literature about species functional traits to explain the observed patterns. Results: Most BSC species were present in both vegetated mounds and intermounds, and variations in community composition between microhabitat were mainly related to differences in the relative cover of each species. BSC cover improved soil surface stability in both microhabitat, irrespective of the community composition. However, soil functions related to nutrient cycling and water dynamics were correlated to changes in BSC composition, varying in dependence of the cover of species of lichens and mosses characterized by different morphological, anatomical and physiological traits. Most community composition/function relationships did not differ between microhabitat. Conclusion: Our results provide novel evidence that changes in BSC species and functional groups create soil heterogeneity in key soil properties and processes, and those effects are no context-dependent in terms of microhabitat. We identified some functional attributes of the species that may deserve greater attention for improving BSC functional-trait analyses in diverse natural communities.Fil: Bustos, Maximiliano Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Garibotti, Irene Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Cech, Norma. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud; ArgentinaFil: Navarro, Cecilia. Universidad Nacional del Comahue. Facultad de Ciencias del Ambiente y la Salud; ArgentinaFil: Gonzalez Polo, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Satti, Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Analysis of the clonal relationship among clinical isolates of Salmonella enterica serovar Infantis by different typing methods Análisis de la relación clonal entre aislamientos clínicos de Salmonella enterica serovar Infantis mediante diferentes métodos de tipificación

Salmonella Infantis has been the second most common serovar in Argentina in the last two years, being isolated mostly from paediatric hospitalised patients. In order to determine the clonal relationship among Salmonella Infantis strains, we examined 15 isolates from paediatric patient faeces in Argentina (12 geographically related and 3 geographically non-related) by using antimicrobial susceptibility, plasmid profiling, repetitive extragenic palindromic (REP) PCR, enterobacterial repetitive intergenic consensus (ERIC) PCR, and low-frequency restriction analysis of chromosomal DNA by pulsed field gel electrophoresis (PFGE). Four Spanish strains were included as controls of clonal diversity in molecular techniques. Antibiotype and plasmid profile was not useful as epidemiological tools. PFGE and REP-PCR were able to discriminate between Argentinean and Spanish isolates of Salmonella Infantis allowing to detect genetically related strains in three different cities. This finding indicates that a possible spread of a clone of this serovar in the North-eastern Region of Argentina has taken place in 1998.<br>Salmonella Infantis ha sido el segundo serovar más común en la Argentina en los últimos dos años, siendo aislada principalmente, a partir de pacientes pediátricos hospitalizados. La relación clonal entre 15 aislamientos de Salmonella Infantis obtenidos de heces de pacientes pediátricos en Argentina se estudió mediante la susceptibilidad antimicrobiana, el perfil plasmídico, amplificación por reacción en cadena de la polimerasa (PCR) de las secuencias repetitivas REP y ERIC, y electroforesis de ADN total en campo pulsátil (PFGE). Cuatro cepas españolas fueron incluidas como control de diversidad clonal. El antibiotipo y el perfil plasmídico no fueron herramientas útiles en la tipificación. PFGE y REP-PCR fueron capaces de discriminar entre las cepas argentinas y españolas de Salmonella Infantis, permitiendo detectar cepas genéticamente relacionadas en tres ciudades diferentes. Este hallazgo indica que una posible diseminación clonal de este serovar ha tenido lugar en la región nordeste de Argentina en 1998