Biotechnological potential of novel glycoside hydrolase family 70 enzymes synthesizing α-glucans from starch and sucrose

Transglucosidases belonging to the glycoside hydrolase (GH) family 70 are promising enzymatic tools for the synthesis of α-glucans with defined structures from renewable sucrose and starch substrates. Depending on the GH70 enzyme specificity, α-glucans with different structures and physicochemical properties are produced, which have found diverse (potential) commercial applications, e.g. in food, health and as biomaterials. Originally, the GH70 family was established only for glucansucrase enzymes of lactic acid bacteria that catalyze the synthesis of α-glucan polymers from sucrose. In recent years, we have identified 3 novel subfamilies of GH70 enzymes (designated GtfB, GtfC and GtfD), inactive on sucrose but converting starch/maltodextrin substrates into novel α-glucans. These novel starch-acting enzymes considerably enlarge the panel of α-glucans that can be produced. They also represent very interesting evolutionary intermediates between sucrose-acting GH70 glucansucrases and starch-acting GH13 α-amylases. Here we provide an overview of the repertoire of GH70 enzymes currently available with focus on these novel starch-acting GH70 enzymes and their biotechnological potential. Moreover, we discuss key developments in the understanding of structure-function relationships of GH70 enzymes in the light of available three-dimensional structure structures, and the protein engineering strategies that were recently applied to expand their natural product specificities.</p

Cellulose nanocrystal reinforced acylglycerol-based polyurethane foams

This work presents the preparation of polyurethane composite foams based on castor oil or modified canola oil as a polyol, and cellulose nanocrystals (CN) as nanofiller (0.10, 0.25, and 0.50 wt% of CN content). The bio-based composites were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), and mechanical properties. The SEM images showed that composite foams had smaller cell sizes and more irregular than those observed for unloaded samples. FTIR revealed that the urethane/urea bond formation was influenced by the incorporation of CN, and was dependent on the polyol used in the formulation. The incorporation of CN did not affect the thermal stability, but the density and mechanical properties changed differently depending on the selected polyol. These results suggested that the acylglycerol structure affects the role of CN in the formulation. Also, the proliferation of MC3T3-E1 preosteoblastic cells showed that the cell viability of polyurethane bionanocomposite foams increased significantly in comparison to the unloaded material.Fil: Gangoiti, Maria Virginia. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Peruzzo, Pablo Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Universidad Nacional Arturo Jauretche; Argentin

Sistema de monitorización y control de conexiones entre Sistemas Autónomos

En las últimas décadas ha aumentado el uso de Internet drásticamente y en paralelo también las relaciones entre Sistemas Autónomos, que son las entidades que constituyen Internet. Sin embargo, a día de hoy los Sistemas Autónomos tienen tantos enlaces, que el tráfico que se envía por ellos es casi imposible de controlar. En este proyecto se estudia la situación actual del entorno tecnológico y se propone un diseño, implementación y despliegue software como solución. En este Trabajo Fin de Grado se desarrolla un sistema que monitoriza y supervisa el tráfico que se intercambia entre Sistemas Autónomos que tienen una relación de tipo peering. Para ello, el sistema deberá controlar dicho tráfico en tiempo real y de forma automática y continua, sin la intervención de ningún ser humano. Además, también será capaz de detectar errores de configuración tanto en el sistema interno de la organización como en organizaciones externas, proponiendo una respuesta rápida como corrección.Azken hamarkadetan, Interneten erabilera nabarmen handitu da, eta era berean, Sistema Autonomoen, Internet osatzen duten entitateen, artekoharremanak. Hori dela eta, gaur egungo enpresek elkar trukatutako trafikoa kontrolatzea ia ezinezkoa da, lotura kantitate handiaren ondorioz. Proiektu honetangaur egungo teknologiaren egoera aztertzen da eta irtenbide gisa software baten diseinua, inplementazioa eta hedapena proposatzen dira. Gradu Amaierako Lan honetan peering motatako harremana duten Sistema Autonomoek trukatzen duten trafikoa monitorizatu eta gainbegiratzen duen sistema garatzen da.Horretarako sistemak trafiko hau denbora errealean eta modu automatiko eta etengabean kontrolatu beharko du, gizakiaren parte hartzerik gabe. Gainera, konfigurazio akatsak antzemateko gai izango da, bai erakundearenbarne-sisteman, zein kanpo erakundeetan, zuzenketa moduan erantzun azkar bat proposatuz.In recent decadesthe use of the Internet has increased significantly and in parallel also the relationshipsbetween Autonomous Systems, which are the entities that constitute Internet. However, nowadays companies have so many links that the traffic sent by them is almost impossible to control. In this project the current situation of the technological world is studied and a design, implementation and software deployment is proposed as a solution. In this Endof Degree Project, a system that monitors and supervises the traffic that is exchanged between Autonomous Sytems that have peering type relationships is developed. For that, the system must control such traffic in real time, automatically and continously, withoutthe intervention of any human being.In addition, it will also be able to detect configuration errors,both in the internal system of the organizationand in external organizations, proposing a quick response as a correction

Automozio sektorerako txapazko osagaiaren simulazio numerikoa

Gradu amaierako lan hau Industria Teknologiako Ingeniaritzako Graduatu titulua eskuratu ahal izateko garatzen da. Hemen, automobil baten xaflazko pieza baten fabrikazio prozesuaren simulazio numerikoa azalduko da. Bertan, ingeniaritza sailean landutako zereginak zehaztuko dira. Honen helburu nagusia, trokelgintza eta simulazio softwarearen ezaguera ona izatea izango da. Helburu honen bitartez, lehen eskutik automozio sektorearen ingeniari baten funtsezko lana ezagutu daiteke. Hasteko, fabrikatu beharreko pieza aztertzen da eta hau fabrikatzeko prozesua aurkezten da: enbutizioa. Ondoren, hau egiteko dauden aukerak aztertzen dira, prozesua ekonomia ikuspuntutik bideragarria izan dadin. Diseinua aurrera eramateko Pam-Stamp programa informatikoarekin egin da eta prentsa mota ezberdinak eta haien ezaugarriak ikertu dira prozesu honetarako aproposena aurkituz.Este trabajo final se desarrolla para obtener el Grado en Ingeniería de Tecnología Industrial. Aquí, aparecerá la simulación numérica del proceso de fabricación de una parte de un automóvil. En él, se determinarán las tareas llevadas a cabo en el departamento de ingeniería. El objetivo principal de esto es tener un buen conocimiento del software de troquelado y simulación. Con este objetivo, uno puede conocer en primer lugar el papel clave de un ingeniero del sector automotriz. Para comenzar, se analiza la pieza a fabricar y se presenta el proceso de fabricación: estampado. A continuación, se analizan las opciones para hacer esto para que el proceso sea viable desde el punto de vista económico. El programa de computadora Pam-Stamp fue diseñado para llevar a cabo el diseño, descubriendo los diferentes tipos de prensa y sus características que se adaptan mejor a este proceso.This final project is developed to obtain the Degree in Industrial Technology Engineering. Here, the numerical simulation of the manufacturing process of a part of an automobile sheet will appear. In it, the tasks carried out in the engineering department will be determined. The main objective of this is to have a good knowledge of the die-cutting and simulation software. With this goal, one can firstly know the key role of an automotive sector engineer. To begin, the piece to be manufactured is analysed and the process of manufacturing is presented: stamping. Next, the options for doing this are analysed to make the process viable from the economic point of view. The Pam-Stamp computer program was designed to carry out the design, finding out about the different types of press and their features that are best suited to this process

Armeriaeuscadiensis eta Txilardi Lehor Europarra (4030): kontserbazio-egoera faboragarria bultzatzeko plana Matxitxakoko lurmuturrean

26 p. : il.-- Bibliogr.: p. 23-26Matxitxakoko lurmuturra, Gaztelugatxeko Biotopoa eta Urdaibaiko Biosfera Erreserbaren artean kokatzen da, baina ez du inolako babes figurarik, gune horretan Armeria euscadiensis espezie endemikoa eta intereseko habitata den Txilardi Lehor Europarra agertzen badira ere. Biotopoaren deklarazio dokumentuan, eremua izendatzeko Armeria euscadiensis landare endemikoa hartu zen kontuan, baina izatez, ez da Biotopoaren barruan kokatzen. Horrez gain, legeek, Gaztelugatxeko Kontzerbazio Bereziko Eremuak zein Armeria euscadiensis-ek kudeaketa plana behar dutela diote; hala ere, lehenengoak berritu gabeko plana du eta bigarrenak izan ere ez du. Matxitxakoko lurmuturrean Armeria euscadiensis espeziearen 287 multzo daudela ikusi, eta gehiago daudela ondorioztatu da. Bestalde, azterketa eremuko Txilardi Lehor Europarraren egoera aztertuz gero, horren kontserbazioa faboratu beharrean Armeria euscadiensis-i lehentasuna ematea egokiagoa litzatekeela ikusi da. Lan honetan, Matxitxakoko lurmuturrerako Armeria euscadiensis eta Txilardi Lehor Europarrarentzat kudeaketa plan proposamena egin da

The gram-negative bacterium Azotobacter chroococcum NCIMB 8003 employs a new glycoside hydrolase family 70 4,6-α-glucanotransferase enzyme (GtfD) to synthesize a reuteran like polymer from maltodextrins and starch

BACKGROUND: Originally the glycoside hydrolase (GH) family 70 only comprised glucansucrases of lactic acid bacteria which synthesize α-glucan polymers from sucrose. Recently we have identified 2 novel subfamilies of GH70 enzymes represented by the Lactobacillus reuteri 121 GtfB and the Exiguobacterium sibiricum 255-15 GtfC enzymes. Both enzymes catalyze the cleavage of (α1→4) linkages in maltodextrin/starch and the synthesis of consecutive (α1→6) linkages. Here we describe a novel GH70 enzyme from the nitrogen-fixing Gram-negative bacterium Azotobacter chroococcum, designated as GtfD. METHODS: The purified recombinant GtfD enzyme was biochemically characterized using the amylose-staining assay and its products were identified using profiling chromatographic techniques (TLC and HPAEC-PAD). Glucans produced by the GtfD enzyme were analyzed by HPSEC-MALLS-RI, methylation analysis, 1D/2D Lombard et al. (2014) H/ Machius et al. (1995) C NMR spectroscopy and enzymatic degradation studies. RESULTS: The A. chroococcum GtfD is closely related to GtfC enzymes, sharing the same non-permuted domain organization also found in GH13 enzymes and displaying 4,6-α-glucanotransferase activity. However, the GtfD enzyme is unable to synthesize consecutive (α1→6) glucosidic bonds. Instead, it forms a high molecular mass α-glucan with alternating (α1→4) and (α1→6) linkages from amylose/starch, highly similar to the reuteran polymer synthesized by the L. reuteri GtfA glucansucrase from sucrose. CONCLUSIONS: In view of its origin and specificity, the GtfD enzyme represents a unique evolutionary intermediate between family GH13 (α-amylase) and GH70 (glucansucrase) enzymes. GENERAL SIGNIFICANCE: This study expands the natural repertoire of starch-converting enzymes providing the first characterization of an enzyme that converts starch into a reuteran-like α-glucan polymer, regarded as a health promoting food ingredient

Veraneo y urbanización en la costa cantábrica durante el siglo XIX: las playas del Abra de Bilbao

Durante la segunda mitad del siglo XIX se generó a lo largo de la costa del Cantábrico una importante actividad turística ligada a los baños de mar. Surgieron multitud de estaciones de baños, la mayoría de reducido tamaño, pero algunas alcanzaron un gran desarrollo, sobre todo Santander y San Sebastián. En muchos casos estas iniciativas turísticas significaron un impulso clave en el desarrollo urbano de esos lugares. En este punto destacan los organizados alrededor de las playas del Abra de Bilbao, por la estrecha y peculiar ligazón entre promoción turística y planificación urbanística