Brucella abortus ure2 region contains an acid-activated urea transporter and a nickel transport system

<p>Abstract</p> <p>Background</p> <p>Urease is a virulence factor that plays a role in the resistance of <it>Brucella </it>to low pH conditions, both <it>in vivo </it>and <it>in vitro</it>. <it>Brucella </it>contains two separate urease gene clusters, <it>ure1 </it>and <it>ure2</it>. Although only <it>ure1 </it>codes for an active urease, <it>ure2 </it>is also transcribed, but its contribution to <it>Brucella </it>biology is unknown.</p> <p>Results</p> <p>Re-examination of the <it>ure2 </it>locus showed that the operon includes five genes downstream of <it>ureABCEFGDT </it>that are orthologs to a <it>nikKMLQO </it>cluster encoding an ECF-type transport system for nickel. <it>ureT </it>and <it>nikO </it>mutants were constructed and analyzed for urease activity and acid resistance. A non-polar <it>ureT </it>mutant was unaffected in urease activity at neutral pH but showed a significantly decreased activity at acidic pH. It also showed a decreased survival rate to pH 2 at low concentration of urea when compared to the wild type. The <it>nikO </it>mutant had decreased urease activity and acid resistance at all urea concentrations tested, and this phenotype could be reverted by the addition of nickel to the growth medium.</p> <p>Conclusions</p> <p>Based on these results, we concluded that the operon <it>ure2 </it>codes for an acid-activated urea transporter and a nickel transporter necessary for the maximal activity of the urease whose structural subunits are encoded exclusively by the genes in the <it>ure1 </it>operon.</p

Screening, characterization and the novo sequencing of broccoli plasma membrane aquaporins by high resolution mass spectrometry

Comunicaciones a congreso

3D Cell Cultures as Prospective Models to Study Extracellular Vesicles in Cancer

The improvement of culturing techniques to model the environment and physiological conditions surrounding tumors has also been applied to the study of extracellular vesicles (EVs) in cancer research. EVs role is not only limited to cell-to-cell communication in tumor physiology, they are also a promising source of biomarkers, and a tool to deliver drugs and induce antitumoral activity. In the present review, we have addressed the improvements achieved by using 3D culture models to evaluate the role of EVs in tumor progression and the potential applications of EVs in diagnostics and therapeutics. The most employed assays are gel-based spheroids, often utilized to examine the cell invasion rate and angiogenesis markers upon EVs treatment. To study EVs as drug carriers, a more complex multicellular cultures and organoids from cancer stem cell populations have been developed. Such strategies provide a closer response to in vivo physiology observed responses. They are also the best models to understand the complex interactions between different populations of cells and the extracellular matrix, in which tumor-derived EVs modify epithelial or mesenchymal cells to become protumor agents. Finally, the growth of cells in 3D bioreactor-like systems is appointed as the best approach to industrial EVs production, a necessary step toward clinical translation of EVs-based therapy.The review is supported by Spanish Ministry of Science and Innovation, within the national Plan RTI2018-094969-B-I00, and Excellence Severo Ochoa grant Innovative Research Grant (SEV-2016- 0644), and by the European Union’s Horizon 2020 research and innovation program, grant number 860303

How reproducible are surface areas calculated from the BET equation?

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMPorosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer–Emmett–Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro- and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This round-robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called “BET surface identification” (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possibl

Estudio de la etapa de mezclado en el desarrollo de los bioplásticos a base de proteína de guisante

El desarrollo de bioplásticos podría ayudar a combatir el problema medioambiental derivado del uso masivo de plásticos procedentes del petróleo, contribuyendo a la producción de materiales de mayor degradabilidad. Todos los bioplásticos objeto de estudio del presente trabajo poseen una relación proteína/plastificante igual a 60/40. Los bioplásticos se obtuvieron en un proceso que consta de una primera etapa de mezclado, resultando una masa homogénea que fue sometida posteriormente a una segunda etapa de moldeo por inyección. El adecuado control de estas etapas es una parte fundamental en el proceso de elaboración de bioplásticos, por lo que el objetivo principal de este trabajo ha sido explorar la influencia de la velocidad de mezclado sobre las masas y los bioplásticos resultantes. Para ello, se realizó una caracterización de los mismos mediante el estudio de su capacidad de absorción de agua, ensayos mecánicos de tracción, y ensayos reológicos en modo dinámico. Entre los resultados obtenidos, puede destacarse que a bajas velocidades de mezclado resultan masas heterogéneas con variabilidad en sus propiedades.The development of bioplastics could avoid the environmental problem derived from the huge use of petroleum-based plastics and contribute to the production of more degradable materials. In this study, bioplastics have a protein/plasticizer ratio of 60/40 from pea protein and glycerol, respectively. They were manufactured in two stages. Firstly, a mixing stage, in which the resulting dough was use in the second stage, an injection molding. The control of these stages is a fundamental part in the process. The main objective of this work is to explore the influence of the speed of mixing on the dough and bioplastics. The characterization of bioplastics was performed by means of water absorption capacity and rheological dynamic tests. Among the results, it can be highlighted that a heterogeneous dough with variability in their properties appears at low mixing speeds.Plan Propio de la Universidad de Sevilla Proyecto: 2017/00000962Ministerio de Economía, Industria y Competitividad (España) / FEDER, UE CTQ2015-71164

Diseño y control de filtros activos mediante simulación HIL

La implementación de los filtros activos es una de las soluciones más eficientes a la problemática que plantea el creciente uso de cargas no lineales en la red eléctrica y la proliferación de cargas distribuidas provenientes de energías renovables conectadas a la misma. El diseño de un filtro activo y del algoritmo para su control pueden realizarse mediante la simulación “Hardware in the loop” (HIL) en tiempo real. Estas simulaciones sirven de interfaz entre el modelo matemático de todos los elementos dinámicos relacionados con el sistema eléctrico bajo control (simulación de la planta) y el sistema integrado bajo prueba. En este trabajo se ha desarrollado la simulación en la máquina virtual de Typhoon HIL, tanto del modelo del filtro activo como de su algoritmo de control. Tras la comprobación de los modelos se ha implementado el algoritmo en una tarjeta de procesamiento digital (DSP). Para la elaboración del código de programación necesario en este sistema de control de prueba se incorporan las herramientas Simulink de Matlab y Code Composer Studio (CCS). Los resultados han sido satisfactorios en general y ofrecen la posibilidad de la implementación física del sistema propuesto con un coste reducido.Active Power Filter implementation is one of the most efficient solutions for problems which raises non-linear loads in the electric net and proliferation of the distributed charges which are coming from the connection of renewable energy sources. The active filter design and its control algorithm can do with the real time simulation “Hardware in the loop” (HIL). These simulations work as interface between the mathematician model of all dynamic elements, which relate to the under control electric system, and the integrated system which is under test. In this project, the simulation in the virtual machine of Typhoon HIL has been developed, including the filter active model and its control algorithm. After checking the model, the algorithm has been implanted in a digital signal processor card. To write the necessary programming code in this embedded system under test, Simulink of Matlab and Code Composer Studio tools are used. In general, results have been satisfactory, so the designed model give us the chance of implementing physically the system with a reduced price

El nuevo paradigma de la industria 4.0 y su aplicación a la industria agroalimentaria

El concepto Industria 4.0 se corresponde con el nuevo paradigma de la industria digitalizada e interconectada. El desarrollo tecnológico que estamos viviendo permite fabricar con un nivel de valor agregado cada vez más alto, y el sector agroalimentario no es una excepción en este nuevo escenario. Se han planteado tres líneas de trabajo para desarrollar durante la investigación planificador de la demanda, mantenimiento predictivo y gestión energética inteligente. Para ello se plantearán una serie de hipótesis que se validarán mediante su aplicación en las instalaciones que Procavi tiene en su planta de Marchena. Centrándonos en la industria agroalimentaria se analizará las nuevas oportunidades y retos, evolucionar del nuevo paradigma industrial.The Industry 4.0 concept corresponds to the new paradigm of the digitalized and interconnected industry. The technological development that can currently be manufactured with a level of added value at the same time, and the agri-food sector is no exception in this new scenario. The current technological development allows manufactured with a high level of added value, and the agri-food sector is no exception in this new scenario. Three lines of work have been proposed for the development during the investigation, the demand planner, the predictive maintenance and the intelligent energy management. To this end, a series of hypotheses will be proposed that will be validated through their application in the facilities that Procavi has in Marchena. Focusing on the agri-food industry, we analyze the new opportunities and challenges, evolution of the new industrial paradigm.Plan Propio de la Universidad de Sevilla Proyecto: 2017/0000096