12 research outputs found

    Bacterial laccases: some recent advances and applications

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    Laccases belong to the large family of multi-copper oxidases (MCOs) that couple the one-electron oxidation of substrates with the four-electron reduction of molecular oxygen to water. Because of their high relative non-specific oxidation capacity particularly on phenols and aromatic amines as well as the lack of requirement for expensive organic cofactors, they have found application in a large number of biotechnological fields. The vast majority of studies and applications were performed using fungal laccases, but bacterial laccases show interesting properties such as optimal temperature above 50 °C, optimal pH at the neutral to alkaline range, thermal and chemical stability and increased salt tolerance. Additionally, bacterial systems benefit from a wide range of molecular biology tools that facilitates their engineering and achievement of high yields of protein production and set-up of cost-effective bioprocesses. In this review we will provide up-to-date information on the distribution and putative physiological role of bacterial laccases and highlight their distinctive structural and biochemical properties, discuss the key role of copper in the biochemical properties, discuss thermostability determinants and, finally, review biotechnological applications with a focus on catalytic mechanisms on phenolics and aromatic amines.info:eu-repo/semantics/publishedVersio

    The spatial structure of lithic landscapes : the late holocene record of east-central Argentina as a case study

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    Fil: Barrientos, Gustavo. División Antropología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Catella, Luciana. División Arqueología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Oliva, Fernando. Centro Estudios Arqueológicos Regionales. Facultad de Humanidades y Artes. Universidad Nacional de Rosario; Argentin

    Hunting Blinds in the Southern End of the Deseado Massif: Collective Hunting Strategies During the Late Holocene

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    The Southern End of the Deseado Massif (SDM, Patagonia, Argentina) is part of a morphostructural region with seasonal shallow lakes and streams highly dependent on rainfall. The area is rich in rock shelters and both primary and secondary sources of high-quality siliceous rocks. To the South there are basaltic plateaus and open plains where no such sources have been identified. Although a relatively big space was explored, rock structures forming groups were located in only a small part of it. In this paper we seek to analyze the reasons for their location and the way in which they were used. In order to do this, we present information related to their frequency, characteristics, and the archaeological context recovered. In addition, in order to understand the way in which they were used, the visibility of nearby environments was analyzed with Geographical Information Systems, using a DEM (Digital Elevation Model) developed by the Argentine Instituto Geográfico Nacional(IGN). Results obtained indicate that the rock structures were built in places higher than the surroundings, using immediately available rocks. According to the visibility analysis, they worked in an articulated way as part of collective hunting strategies. The characteristics and composition of the artifact assemblages recovered indicate that different activities took place at these sites during the Late Holocene. The identification of the hunting blinds in a specific area within the SDM and their absence in the remaining study area to the North and South suggest that this area was selected for planned collective hunting.Fil: Franco, Nora Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; Argentina. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Departamento de Ciencias Antropológicas; ArgentinaFil: Vetrisano, Lucas Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; ArgentinaFil: Gilio, Brenda Ludmila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Tecnológica Nacional. Facultad Regional Santa Cruz. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia de Santa Cruz; ArgentinaFil: Cirigliano, Natalia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; ArgentinaFil: Bianchi, Pablo Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; Argentin

    Hunting Landscapes in the North Margin of Lake Viedma (Southern Patagonia, Argentina): Preys, Strategies and Technology

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    The aim of this paper is to describe and discuss the strategies and technology implemented by Late Holocene hunter-gatherers to hunt their most prominent animal resources, guanaco (Lama guanicoe) and choique (Rhea pennata pennata), in different settings in the north margin of Lake Viedma (Santa Cruz province, Argentina). In order to do that, we use archaeological distributional data from different altitudinal levels, namely lakeshore dunes (255–275 m.a.s.l), mid-altitude plains or pampas (276–900 m.a.s.l.), and Del Tobiano basaltic plateau (≥900 m a.s.l.). The pampas, particularly the grounds below 400 m.a.s.l., may have been used by both species as their wintering grounds (although their permanence in this environment could have occurred throughout the year), while the mid-altitude plains and the plateau seem to have been primarily used by the guanaco as grazing and calving grounds from late spring to early fall, the months in which most of its surface is free of snow. Likely, differences in seasonality, topography and use of these environments by the guanaco and choique social groups may have forced people to adopt different hunting strategies, tactics and weaponry. Frequency variations in the presence of projectile points and bolas at different altitudinal levels have been observed. In the pampas, evidence suggests that guanaco hunting was aided by the use of bow and arrows and/or throwing weapons, such as spears and bolas, the latter likely also used in the hunting of choique. In the plateau, on the other hand, guanaco hunting tactics involved the use of blinds either by individuals or small groups of hunters who were mainly equipped with throwing weapons and/or bow and arrows. The archeological record of the plateau shows a logistic hunting-oriented strategy as well as a residential use during summer months. Artifact density and variety at lakeshore dunes suggest a greater intensity of occupation of these grounds, probably linked to a more residential use—either seasonal (fall/winter) or year-round—made possible by the availability, although in variable density throughout the year, of guanaco and choique. Consequently, the regional archeological landscape exhibits evidence of integration and complementarity of the different altitudinal levels in the northern margin of the Lake Viedma, at least during the Late Holocene.Fil: Belardi, Juan Bautista. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral; ArgentinaFil: Carballo Marina, Flavia Elena. Universidad Nacional de la Patagonia Austral; ArgentinaFil: Barrientos, Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin

    UNR/CDSE1 expression as prognosis biomarker in resectable pancreatic ductal adenocarcinoma patients: A proof-of-concept

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    Pancreatic ductal adenocarcinoma is an aggressive form of pancreatic cancer and the fourth leading cause of cancer-related death. When possible, curative approaches are based on surgical resection, though not every patient is a candidate for surgery. There are clinical guidelines for the management of these patients that offer different treatment options depending on the clinical and pathologic characteristics. However, the survival rates seen in this kind of patients are still low. The CDSE1 gene is located upstream of NRAS and encodes an RNA-binding protein termed UNR. The aim of this study was to analyze UNR expression and its correlation with outcome in patients with resectable pancreatic ductal adenocarcinoma (PDAC). For this, samples from resectable PDAC patients who underwent duodenopancreatectomy were used to evaluate UNR protein expression by immunohistochemistry using a tissue microarray. Here, we observed that low UNR expression was significantly associated with shorter progression-free survival after surgery (P = 0.010). Moreover, this prognostic marker remained significant after Cox proportional hazards model (P = 0.036). We further studied the role of CDSE1 expression in patient's prognosis using data from public repositories (GEO and TGCA), confirming our results. Interestingly, CDSE1 expression correlated with that of genes characteristic of an immunogenic molecular subtype of pancreatic cancer. Based on these findings, UNR may be considered a potential prognostic biomarker for resectable PDAC and may serve to guide subsequent adjuvant treatment decisions.This work has been carried out with the support of the RNA-Reg CONSOLIDER Network CSD2009-00080 (J.M.-U. and J.G.-F.), and Spanish Health Research Project Funds PI16/01468 from “Instituto de Salud Carlos III” (A.C. and J.G.-F.), both of the Spanish Ministry of Economy, Industry and Competitiveness

    Synthesis of 5,6- and 6,6-Spirocyclic Compounds

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    The Spatial Structure of Lithic Landscapes: the Late Holocene Record of East-Central Argentina as a Case Study

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