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We present the MARAS (Environmental Monitoring of Arid and Semiarid Regions) dataset, which stores vegetation and soil data of 426 rangeland monitoring plots installed throughout Patagonia, a 624.500 km2 area of southern Argentina and Chile. Data for each monitoring plot includes basic climatic and landscape features, photographs, 500 point intercepts for vegetation cover, plant species list and biodiversity indexes, 50-m line-intercept transect for vegetation spatial pattern analysis, land function indexes drawn from 11 measures of soil surface characteristics and laboratory soil analysis (pH, conductivity, organic matter, N and texture). Monitoring plots were installed between 2007 and 2019, and are being reassessed at 5-year intervals (247 have been surveyed twice). The MARAS dataset provides a baseline from which to evaluate the impacts of climate change and changes in land use intensity in Patagonian ecosystems, which collectively constitute one of the world´s largest rangeland areas. This dataset will be of interest to scientists exploring key ecological questions such as biodiversity-ecosystem functioning relationships, plant-soil interactions and climatic controls on ecosystem structure and functioning., Measurement(s) vegetation layer • biodiversity assessment objective • concentration of carbon atom in soil • acidity of soil • concentration of nitrogen atom in soil • structure of soil Technology Type(s) quadrat sampling • line intercept sampling • visual observation method • Walkley-Black Method • pH measurement • Kjeldahl method • Bouyoucos method Factor Type(s) measurement time & location Sample Characteristic - Organism Plantae Sample Characteristic - Environment arid biome • arid subtropical Sample Characteristic - Location Patagonia Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12761936

Una elevada proporción del territorio argentino corresponde a tierras secas y una tercera parte de éstas se hallan en la Patagonia. Esta región históricamente ha sufrido procesos de deterioro del pastizal. Generalmente, la degradación es atribuida al uso ganadero; sin embargo, el efecto del clima sobre estos sistemas ha sido poco analizado. El objetivo de este trabajo fue analizar la evolución del clima y de los pastizales naturales, a través de la identificación de variables que permitan comprender los posibles cambios en las existencias ganaderas para el noroeste de la provincia de Chubut, en el período 2000-2014. Para ello se analizaron diferentes tipos de datos: climáticos, índice verde normalizado (NDVI), lecturas de monitores MARAS y existencias ganaderas. Los resultados indican incrementos de temperatura y tendencias negativas de la productividad y estructura del pastizal. Asimismo se observó una disminución de las existencias ganaderas. El incremento de las temperaturas podría estar relacionado con balances hídricos desfavorables, los cuales, combinados con el sobrepastoreo, pueden ser factores claves en los procesos de deterioro del pastizal. Resulta fundamental continuar con el monitoreo de las diferentes variables que caracterizan a estos sistemas y diseñar estrategias que permitan mitigar los procesos descriptos. Most of Argentina territory is classified as dry lands, one third of them is located in Patagonia. The grasslands in this region have been historically affected by deterioration. This degradation has been associated to excessive grazing. However, little attention has been paid to the effect of climate on these systems. The aim of this work was to examine the evolution of climate and grasslands in NW Chubut between 2000-2014, identifying variables that allow a better understanding of the causes of changes in livestock numbers. Different types of data have been analysed: weather statistics, normalized difference vegetation index (NDVI), information from MARAS monitors and livestock numbers. Results show a temperature increase and negative trends of grasslands productivity and structure during the period. Additionally, a decline in the livestock numbers was observed. Rising temperatures could negatively affect hydric balance which, along with overgrazing, could be key factors affecting grassland deterioration. It is of fundamental importance to keep monitoring these variables and to devise mitigation strategies against the processes described. Fil: García Martínez, Guillermo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Ciari, Georgina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Gaitán, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Suelos; Argentina Fil: Carusso, Mauro Cesar. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Nagahama, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Opazo, W.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Nakamatsu, V.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional.patagonia Sur. Estación Experimental Agropecuaria Chubut; Argentina Fil: Lloyd, C.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Cotut, C.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Irisarri, Jorge Gonzalo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Forrajicultura; Argentina Fil: Escobar, J.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional.patagonia Sur. Estación Experimental Agropecuaria Chubut; Argentina

En este estudio se analizó la calidad y el comportamiento germinativo de semillas de diferentes poblaciones localizadas en un gradiente de precipitación anual oeste-este (500 a 150 mm) en cuatro especies de gramíneas forrajeras nativas (Bromus setifolius, Hordeum comosum, Festuca pallescens y Poa ligularis), del NO de Chubut. Se estimó el peso y el porcentaje de semillas llenas a nivel inter- e intra-específico. Las semillas fueron sembradas en un ambiente común y se calculó el porcentaje de germinación y la velocidad de emergencia para las especies y las poblaciones. En este trabajo se presentan datos relacionados a la germinación de semillas recolectadas en un año en particular (2015) de estas cuatro especies y se discuten principalmente los resultados obtenidos para P. ligularis, la especie que presentó mayor variabilidad entre las poblaciones analizadas. En P. ligularis un gran porcentaje de semillas de la población del sitio más árido germinaron/emergieron en menos días. Esta característica podría estar asociada a adaptaciones fisiológicas de las plantas para germinar, emerger y establecerse rápidamente ante la escasa disponibilidad de agua en este sitio. Los genotipos de esta población particular podrían ser utilizados para programas de restauración de ambientes áridos con precipitación media anual menor a 150 mm. Finalmente, debido a la variabilidad observada al menos en P. ligularis, se sugiere que para futuros programas de mejoramiento con estas especies nativas sería necesario analizar un mayor número de poblaciones para seleccionar los potenciales bancos de semilla. In this study, we analyzed the quality and germination behavior of seeds from different populations located on a west-east annual precipitation gradient (500 to 150 mm) in four species of native Patagonian forage grasses (Bromus setifolius, Festuca pallescens, Hordeum comosum and Poa ligularis), from NW Chubut. We observed differences in weight and percentage of filled seeds at inter- and intra-specific level. The seeds were sown in a common environment and the germination percentage and emergence speed were calculated for species and populations. We present data related to the germination of seeds (harvested in 2015) of these four species and we discuss primarily the results obtained from P. ligularis, the species that presented the highest inter-populational variability. In P. ligularis, a large percentage of seeds from the population of the driest site germinated/emerged in fewer days. This characteristic could be associated with these plants adapting physiologically to germinate, emerge and establish themselves quickly in response to the limited availability of water in this area. The genotypes of this particular population could be used for restoration programs in arid environments with annual rainfall less than 150 mm. Finally, due to the variability observed at least in P. ligularis, it is suggested for future breeding programs with these native species it would be necessary to analyze a greater number of populations to select potential seed banks. Fil: Nagahama, Nicolas. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: García Martínez, Guillermo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Buduba, Carlos Guillermo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Opazo, Walter. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Caruso, Cecilia Alejandra. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina Fil: Ciari, Georgina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; Argentina

Enquanto as células humanas sintetizam purinas pela via de novo e pela via de recuperação, protozoários parasitas as sintetizam somente pela via de recuperação. Por essa razão, as enzimas que compõem essa via são importantes alvos para o desenvolvimento de novas drogas antiparasitárias. A enzima APRT converte adenina e &#945-D-5-fosforibosil 1-pirofosfato (PRPP) a AMP na via de recuperação de purinas. Nesse trabalho, a APRT e a APRT-His recombinantes foram caracterizadas por métodos bioquímicos e espectroscópicos. As expressões do gene aprt contidos nos vetares pET29+ (Novagen) e pQE30 (Qiagen) renderam 5 e 10 mg.mL-1 de APRT e APRT-His, respectivamente, na forma solúvel. A APRT permaneceu estável e homogênea in vitro em Tris pH 7,5 contendo 5 mM de MgSO4 e 150 mM de KCl mas a APRT-His mostrou-se instável e insolúvel nesse pH e acima de 0,5 mg.mL-1. O estudo de solubilidade revelou que a APRT-His é parcialmente estabilizada em Tris pH 8,5 contendo 150 mM de KCl devendo ser purificada e mantida nesse tampão durante os ensaios espectroscópicos e a adição de 50 mM de histidina mostrou-se eficiente para a concentração da enzima até 8mg.mL-1. A caracterização bioquímica da APRT e da APRT-His revelou que elas são diméricas nos seus tampões e têm PI igual a 6,45 &#177 0,20 e 7,7 &#177 0,16, respectivamente. Os ensaios de atividade enzimática indicaram que a APRT é duas vezes mais ativa do que a APRT-His. Os espectros de CD da APRT-His foram mais intensos do que os espectros da APRT e mostraram perfil de hélice &#945 . Os resultados da desconvolução revelaram que a APRT-His tem cerca de 10% mais hélice-&#945 do que a APRT. O valor de teor de estrutura secundária da APRT equivale aos valores extraídos dos dados cristalográficos da APRT de L donovani e de L tarentolae. Os espectros de emissão de fluorescência mostraram que a APRT-His e a APRT possuem máximos de emissão em 342 e 332 nm, respectivamente. Além disso, eles indicaram que o PRRP e o AMP suprimem a fluorescência do Trp presente na APRT. A supressão foi relacionada à posição dos ligantes localizados no sítio ativo da enzima e a ausência de supressão nas amostras de APRT-His foi relacionada à presença de Mg2+. Os resultados indicam que a presença dos resíduos de histidina na região N-terminal da APRT-His induziu a modificação estrutural da enzima levando a precipitação contínua. Nesse sentido, a ausência dos resíduos de histidina incorporados à enzima favoreceu a estabilidade da proteína in vitro. Human cells synthesize purine nucleotide by again and salvage pathways, while parasitic protozoa use only salvage pathways. For this reason, the enzymes that compound the salvage pathway are important targets to development of new antiparasitic drugs. The enzyme adenine phosphoribosyltransferase (APRT) converts adenine and &#945-D-5-phosphoribosyll-pyraphosphate (PRPP) to adenosine monophosphate (AMP) at salvage pathway. In this work, the APRT and APRT-His recombinants had been characterized by biochemical and spectroscopic methods. The expression of the aprt genes from L. tarentolae inserted into pET29+ (Novagen) and pQ30 (Qiagen) vectors yielded 5 and 10 mg.mL-1 of the APRT and APRT-His, on soluble form, respectively. The APRT remained stable and homogeneous in vitro at Tris pH 7.5 containing 5 mM MgSO4 and 150 mM KCl, but APRT-His was instable and insoluble above 0.5 mg.mL-1 at the same pH. The solubility study showed that histidine increased the APRT-His solubility and it is partially stabilized at Tris pH 8.5 containing 150 mM KCl. The addition of the histidine 50 mM was efficient for concentrations up to 8 mg.mL-1.Then, the APRT-His was purified and storage in that buffer for spectroscopic assays. The biochemical characterization of the APRT and APRT-His indicated that a both are dimercs in its buffers, and they have isoelectric points at pH 6.45 &#177 0.20 and 7.7 &#177 0.16, respectively. By enzymatic activity assays, the APRT is twice activer than APRT-His. The CD spectra of the APRT-His were more intense than the APRT spectra. and showed helix &#945 profile. The fluorescence spectra marked a maximum emission fluorescence at 342 nm for the APRT-His and 332 um for the APRT. In addition, the spectra revealed that PRPP and AMP quenched the fluorescence of the tryptophan (Trp) into APRT. The quench was related to position of the ligands inside active site of the enzyme and the absent of fluorescence of the Trp, inside APRT-His, was related to absent of the Mg2+. The results has demonstrated that the presence of the histidine residues at N-terminal region of the APRT-His induced to conformational changes of the enzyme following to continuos precipitation. In the same sense, the absent of histidine residues associated to enzyme favored to stability of the protein in vitro.