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In recent years, social networks have become an important communication platform through which candidates promote the political engagement of their constituents.One of the variables that could influence this ability to generate engagement through social networks is the use of messages with a significant emotional charge, both positive and negative. Our research aims to delve into the analysis of this relationshipbetween political engagement and emotions in social networks, through the Sentiment Analysis in the tweets of the main candidates in the general elections of April and November 2019 in Spain. For this we resort to the technique of text extraction and its analysis with the Linguistic Inquiry and Word Count (LIWC) software, relating the level of presence of positive and negative emotions, with the level of engagement reached by the candidates during the electoral campaign. Our analysis helps to demonstrate the existence of a relationship between the emotional charge of the discourse on social networks and the level of engagement it generates, although this seems to be also mediated by the political agenda and the campaign strategy of the parties. We also verify that the relationship between emotional discourse and engagement towards a leader is not exclusively endogenous, but may also be due to exogenous elements due to the presence of shared digital communities. Las redes sociales se han convertido en los últimos años en una importante plataforma de comunicación a través de la que los candidatos promueven el compromiso político de sus electores. Una de las variables que podría influir en esa capacidad de generar engagementa través de las redes sociales es la utilización de mensajes con una importante carga emocional, tanto positiva como negativa. Nuestra investigación tiene como objetivo profundizar en el análisis de dicha relación entre el compromiso político y las emociones en las redes sociales, mediante el Análisis de Sentimientos en los tuits de los principales candidatos en las elecciones generales de abril y noviembre de 2019 en España. Para ello recurrimos a la técnica de extracción de textos y su análisis con el software Linguistic Inquiry and Word Count (LIWC), poniendo en relación el nivel de presencia de emociones positivas y negativas, con el nivel de compromiso alcanzado por los candidatos durante la campaña electoral. Nuestro análisis contribuye a demostrar la existencia de relación entre la carga emocional del discurso en las redes sociales y el nivel de engagement que genera, aunque este parece estar mediatizado además por la agenda política y la estrategia de campaña de los partidos. Comprobamos además que la relación entre discurso emocional y engagement hacia un líder no es exclusivamente endógena, sino que puede obedecer también a elementos exógenos debido a la presencia de comunidades digitales compartidas.

espanolIntroduccion: El objetivo que persigue este trabajo es analizar si los diversos usos que los ciudadanos realizan de las redes sociales tienen relacion con el voto a los partidos politicos y con las emociones que los ciudadanos sienten hacia los lideres politicos. De ser asi, podriamos asumir que la plataformizacion es un proceso politizado y emocionado y que esa politizacion y emocionalidad del proceso vincula el tipo de uso que los ciudadanos hacen de las redes. Metodologia: Este trabajo se ha planteado como un estudio de caso mediante un enfoque metodologico cuantitativo que plantea tanto un analisis descriptivo e interdependencia de los datos. Resultados: el analisis del consumo de redes en funcion del voto muestra la existencia de un patron diferenciado en funcion de este ultimo. Una tendencia que se replica en lo relativo al uso especifico de las redes concretas. Discusion: los datos respecto a la expresion emocional de enfado y miedo concuerdan con las posturas defendidas en la literatura. Conclusiones: estos hallazgos se suman a los ya existentes respecto a la importancia de las redes como “camaras de eco” que amplifican los debates que en ellas se producen, en una suerte de “espiral emocional”. EnglishIntroduction: The objective pursued by this research is to determine if there is a diversified use of social networks in our country and what is the relationship that such use has with the vote for political parties that citizens express, as well as with the presence emotional towards political leaders. If so, we could assume that the plataformizacion is a politicized and excited process and that this politicization and emotionality of the process links the type of use those citizens make of the networks. Methodology: This work has been proposed as a case study using a quantitative methodological approach that proposes both a descriptive and interdependency analysis of the data. Results: the analysis of the consumption of networks according to the vote shows the existence of a differentiated pattern according to the latter. A trend that is replicated in relation to the specific use of specific networks. Discussion: the data regarding emotional expression of anger and fear agree with the positions defended in the literature. Conclusions: these findings are in addition to those already existing regarding the importance of networks as "echo chambers" that amplify the debates that occur in them, in a kind of "emotional spiral".

We report the structure and charge transport properties of a novel solid-state proton conductor obtained by acid-base chemistry via proton transfer from 12-tungstophosphoric acid to imidazole. The resulting material (henceforth named Imid3WP) is a solid salt hydrate that, at room temperature, includes four water molecules per structural unit. To our knowledge, this is the first attempt to tune the properties of a heteropolyacid-based solid-state proton conductor by means of a mixture of water and imidazole, interpolating between water-based and ionic liquid-based proton conductors of high thermal and electrochemical stability. The proton conductivity of Imid3WP·4H2O measured at truly anhydrous conditions reads 0.8 × 10-6 S cm-1 at 322 K, which is higher than the conductivity reported for any other related salt hydrate, despite the lower hydration. In the pseudoanhydrous state, that is, for Imid3WP·2H2O, the proton conductivity is still remarkable and, judging from the low activation energy (Ea = 0.26 eV), attributed to structural diffusion of protons. From complementary X-ray diffraction data, vibrational spectroscopy, and solid-state NMR experiments, the local structure of this salt hydrate was resolved, with imidazolium cations preferably orienting flat on the surface of the tungstophosphate anions, thus achieving a densely packed solid material, and water molecules of hydration that establish extremely strong hydrogen bonds. Computational results confirm these structural details and also evidence that the path of lowest energy for the proton transfer involves primarily imidazole and water molecules, while the proximate Keggin anion contributes with reducing the energy barrier for this particular pathway.

[Abstract] We study the microscopic structure and transport properties of ions in mixtures of 1-butyl-3-methylimidazolium and 1-butyl-3-ethylimidazolium iodide with ethanol using atomistic molecular dynamics simulations and conductivity measurements. Compared with the same ionic liquids in water, we reveal essential differences in ionic structure that are closely related to the differences in the solubility mechanisms of both types of solvents. In particular, unlike for aqueous solutions, we find a homogeneous distribution of solvent molecules in the system, i.e., we observe no cluster formation, which agrees with the nano-structured solvation paradigm. In addition, we calculate the conductivities of these systems in the whole concentration range and compare them with experimental data. Although the simulated values slightly underestimate the experimental ones, they reproduce the shape of the experimental conductivity dome reasonably well. We also show that the pseudo-lattice random-alloy model, which is based on microscopic ion jumping frequencies, describes the conductivity data accurately. We compute the average jumping frequencies directly from simulations and find that they agree well with those obtained by fitting the simulation conductivity data. These results show that the pseudo-lattice random-alloy model provides a valuable tool to describe the conductivities of ionic liquid–solvent mixtures and particularly their concentration dependence. It shall also apply to other systems, e.g., inorganic electrolytes and dispersed ionic conductors. The financial support of the Spanish Ministry of Economy and Competitiveness (Projects MAT2017-89239-C2-1-P and MAT2017-89239- C2-2-P) is gratefully acknowledged. Moreover, this work was funded by the Xunta de Galicia (ED431D 2017/06, ED431E 2018/08, GRC ED431C 2016/001 and GRC ED431C 2020/10). All these research projects were partially supported by FEDER. The help of the technician M. C. V. from UDC for some of the measurements presented is also acknowledged. H. M-C. and J. M. O-M. thank the Spanish Ministry of Education for their FPU grant, and H. M-C. thanks the USC for his “Convocatoria de Recualificación do Sistema Universitario Español-Margarita Salas” postdoc grant under the “Plan de Recuperación Transformación” program funded by the Spanish Ministry of Universities with European Union’s NextGenerationEU funds Xunta de Galicia; ED431D 2017/06 Xunta de Galicia; ED431E 2018/08 Xunta de Galicia; ED431C 2016/001 Xunta de Galicia; ED431C 2020/10

Asystematic review of the Mediterranean region species of the sylvicola group of Corticaria Marsham, 1802 is carried out. An identification key for the determination of those 21 species is provided. Morphological structures of the studied species are re-appraised and figures are provided of head, antennae, pronotum, and aedeagus with internal armature. The true identity of Corticaria tunisiensis Brisout de Barneville, 1884 is established by examination of the specimens of the collection of National Museum of Natural History, Paris, here designating a male lectotype and paralectotypes of both sexes.

Over the last few years, European public broadcasters have promoted the concept of public service media as one of their main values. To this end, transparency policies have been implemented as a mechanism of corporate projection by strengthening their role as an essential service. The objective of this article is to ascertain the existence of this type of policies among European public broadcasters. To this end, a nominal group was made with 24 experts who were surveyed, thus generating new indicators of transparency and accountability strategies around sustainability and digitalization. The contents of the websites of RTVE (Spain), RTP (Portugal), France TV (France), RAI (Italy), BBC (UK), RTÉ (Ireland), ZDF (Germany), VRT (Belgium), and SVT (Sweden) were also analyzed, paying attention to such indicators and strategies. The main results include the identification of differences on the basis of the ideal models described by Hallin and Mancini, a commitment to credibility (fact-checking) to the detriment of diversity of opinions, and a connection between the political system and the media system, which, preliminarily, determines the level of transparency of these public entities.

Graphical abstract, Highlights • A novel thermophilic esterase discovered from hot-spring metagenomic library. • EstD11 shows broad substrate specificity including substrates of industrial interest. • Atomic resolution crystallographic complexes reveal hot-spots in the active site. • High-T structures provide unique evidence on cap dynamics as occurs in vivo. • Met zipper at active site essential in thermo-stability and substrate promiscuity., A novel esterase, EstD11, has been discovered in a hot spring metagenomic library. It is a thermophilic and thermostable esterase with an optimum temperature of 60°C. A detailed substrate preference analysis of EstD11 was done using a library of chromogenic ester substrate that revealed the broad substrate specificity of EstD11 with significant measurable activity against 16 substrates with varied chain length, steric hindrance, aromaticity and flexibility of the linker between the carboxyl and the alcohol moiety of the ester. The tridimensional structures of EstD11 and the inactive mutant have been determined at atomic resolutions. Structural and bioinformatic analysis, confirm that EstD11 belongs to the family IV, the hormone-sensitive lipase (HSL) family, from the α/β-hydrolase superfamily. The canonical α/β-hydrolase domain is completed by a cap domain, composed by two subdomains that can unmask of the active site to allow the substrate to enter. Eight crystallographic complexes were solved with different substrates and reaction products that allowed identification of the hot-spots in the active site underlying the specificity of the protein. Crystallization and/or incubation of EstD11 at high temperature provided unique information on cap dynamics and a first glimpse of enzymatic activity in vivo. Very interestingly, we have discovered a unique Met zipper lining the active site and the cap domains that could be essential in pivotal aspects as thermo-stability and substrate promiscuity in EstD11.

Micrambe micoae sp. n. (Coleoptera: Cryptophagidae) from the Iberian Peninsula, the Cabañeros National Park, Ciudad Real, Spain, is described. Differential diagnosis with M. ulicis (Stephens, 1830) is established.

The stability of binary mixtures of several protic ionic liquids (ethylammonium nitrate, ethylammonium acetate and ethylammonium tetrafluoroborate) with polyethylene oxide is studied by means of molecular dynamics simulations. The solubility range is seen to be wider for ethylammonium acetate, and the structure and single-particle dynamics of its ternary mixtures with lithium acetate are then studied. The structure of liquid mixtures of lithium acetate with the ionic liquid is seen to be seldom modified by the addition of the polymer, with very limited hydrogen bonding between the ionic liquid and the polymer taking place. Moreover, lithium is seen to be solvated in the liquid phase forming [Li(ACE)4]−3 tetrahedral complexes irrespective of the presence of the polymer, with very limited binding of metal cations to oxygen atoms in the polymer backbone. Hence, the registered single particle dynamics and lithium transport takes place in practically the same way as in the liquid phase with almost no interference of the polymer, contrarily to previously reported results for other ionic liquids.

Anew species, Monotoma (Monotomina) bousqueti, is described. It was found in La Manga, Province of Murcia, Spain.We present its differences with the nearest known species, M. (M.) quadrifoveolata Aubé, 1837.

We perform molecular dynamics simulations of ionic liquids confined between graphene walls under a large variety of conditions (pure ionic liquids, mixtures with water and alcohols, mixtures with lithium salts and defective graphene walls). Our results show that the formation of striped and hexagonal patterns in the Stern layer can be considered as a general feature of ionic liquids at electrochemical interfaces, the transition between patterns being controlled by the net balance of charge in the innermost layer of adsorbed molecules. This explains previously reported experimental and computational results and, for the first time, why these pattern changes are triggered by any perturbation of the charge density at the innermost layer of the electric double layer (voltage and composition changes, and vacancies at the electrode walls, among others), which may help tuning electrode-ionic liquid interfaces. Using Monte Carlo simulations we show that such structures can be reproduced by a simple two-dimensional lattice model with only nearest-neighbour interactions, governed by highly screened ionic interactions and short-range and excluded volume interactions. We also show that the results of our simulations are consistent with those inferred from the Landau-Brazovskii theory of pattern formation in self-assembling systems. The presence of these patterns at the ionic liquid graphene-electrode interfaces may have a strong impact on the process of ionic transfer from the bulk mixtures to the electrodes, on the differential capacitance of the electrode-electrolyte double layer or on the rates of redox reactions at the electrodes, among other physicochemical properties, and is therefore an effect of great technological interest., 8 pages, 5 figures, Physical Chemistry Chemical Physics

Targeted irreversible inhibitors bearing electrophiles that become activated towards covalent bond formation upon binding to a specific protein/enzyme is an emerging area in drug discovery. Targeting lysine residues is challenging due to the intrinsically low reactivity of the amino group at physiological pH. Herein we report the first example of a hydroxylammonium derivative that causes a specific covalent modification of an active-site and a sterically inaccessible lysine residue of an enzyme. The described ligands, compounds 1–3, were rationally designed to be activated towards covalent bond formation upon binding to the type I dehydroquinase (DHQ1) enzyme for the development of new anti-virulence agents to combat the widespread resistance to antibiotics. Evidence in atomic detail for the covalent modifications caused by the ligands to the catalytic Lys170 by the formation of a stable secondary amine is provided by the resolution at 1.08–1.25 Å of the crystal structures of DHQ1 from Salmonella typhi enzyme adducts. In addition, the first crystal structure of the addition intermediate adduct at 1.4 Å of a Schiff base formation reaction by using an analog of the natural substrate, compound 4, is also reported. Molecular dynamics simulation studies on non-covalent enzyme/ligand complexes and a two-dimensional QM/MM umbrella sampling simulation study suggested that a direct displacement by Lys170 with the release of NH2OH would be feasible. These studies might open up new opportunities for the development of novel lysine-targeted irreversible inhibitors bearing a methylhydroxylammonium moiety as a latent electrophile., Financial support from the Spanish Ministry of Economy and Competiveness (SAF2016-75638-R), the Xunta de Galicia [Centro singular de investigación de Galicia accreditation 2016-2019 (ED431G/09) and ED431B 2018/04] and the European Union (European Regional Development Fund – ERDF) is gratefully acknowledged.

A density functional theory study of the effect of the adsorption of a mixture of potassium salt and an imidazolium-based ionic liquid on the electronic and optical properties of graphene and borophene is performed. This addition leads to a downward shift of the Dirac cone for both structures due to the electron transferred from potassium to the graphene and borophene sheets. The transferred charge to the wall and the binding energy of potassium are bigger than in the case of the adsorption of potassium on pristine graphene. The Bader analysis shows that the presence of potassium makes the charge distributions in graphene and the layers of boron atoms in borophene more homogenous and the electronic distribution in the sheets is consequently less affected by the electromagnetic interaction with the ions in the mixture. Moreover, the results show that the optical properties are altered by the metallic cation, especially at low frequencies where ionic liquid-enhanced 2D plasmons are registered due to the doping of 2D sheets by electrons transferred from the potassium atoms leading to near zero values of the parallel components of the dielectric function and refractive index.

In this work we study how the properties of ionic liquids change upon confinement between two walls at various nanometric distances. We also find a correlation between the dynamic properties and the structure of this system under these extremely nanoconfined circumstances. We report that for ethylammonium nitrate, the ionic structure inside the simulation boxes is a consequence of a subtle combination of ion packing, hydrogen bonding, electrostatic and van der Waals forces. We also study how the dynamical properties of this material change in these conditions, showing a decrease in the ionic mobility for very low slit sizes, recovering the bulk behavior as the distance between walls increases. Moreover, when short wall separations are considered, we show that the ionic mobility at short times is a minimum when the hydrogen bonding is also a minimum. Finally, we show that the effect of the interface in the long time ion dynamics only extends to a quite small region (ca. 1.35 nm) next to the walls. We show that the overall behavior of the nanoconfined liquid in the slit pore can be described by the superposition of a bulk and a confined simulation with a fitted wall separation. To our knowledge, there are no similar studies characterizing this kind of dense ionic systems in such a fine-grain way under these ultra-nanoconfined conditions.

In this paper, we present a molecular dynamics study of ammonia solutions in a protic ionic liquid with a structurally similar cation, ethylammonium nitrate. Using two different models of the ammonia molecule, a conventional 4-site model and a 6-site model optimizing the dipolar and quadrupolar electron distributions, we evaluate their effect on the microstructure and single-particle dynamics of these mixtures, as well as on their behaviour at the electrochemical interface. Quite significant differences are found on the solvation of ammonia in these dense ionic solvents, the 6-atom model predicting a stronger affinity of solvent molecules for the cations of the solvent as well as a caging effect on NH3 solvation shells, not predicted by the 4-site model. Finally, we discuss the structure of the liquid layers near charged graphene walls. The structure in the layer next to the wall varies with the charge on the wall and varies with the model used for ammonia.

12 pags., 17 figs., 1 tab., Molecular dynamics simulations are reported for a protic (ethylammonium nitrate) and an aprotic (1-ethyl-3-methylimidazolium tetrafluoroborate) ionic liquid nanoconfined inside a faujasite-templated carbon. The structure and dynamics of ionic species inside nanotubes of relevant sizes are studied in order to understand the behavior of the dense ionic solvents in the zeolite-templated carbon. The structure (density, coordination numbers) of the confined fluid reflects a mixed dimensionality inside the zeolite-templated carbon, while the single-particle dynamics shows fundamental changes relative to that of ionic liquids confined in carbon nanotubes. Finally, no significant differences are found between the protic and the aprotic ionic liquids, which seems to suggest that the influence of hydrogen bonding is heavily suppressed inside the zeolite-templated carbon., The financial support of the Spanish Ministry of Economy and Competitiveness (Projects MAT2017-89239-C2-1-P and MAT2017-89239-C2-2-P) is gratefully acknowledged. Moreover, this work was fundedby the Xunta de Galicia (ED431D 2017/06, ED431E 2018/08 and GRCED431C 2016/001). All these research projects were partially supportedby FEDER. H.M.-C. and J.M.O.-M. thank the Spanish Ministry of Education for their FPU grant. T. M.-M. thanks the Spanish Ministry of Science,Innovation and Universities for her Juan de la Cierva grant (IJC2018-036774-I). E.L acknowledges the support from the Agencia Estatal deInvestigación and Fondo Europeo de Desarrollo Regional (FEDER) undergrant No. FIS2017-89361-C3-2-P. Facilities provided by the Galician Supercomputing Centre (CESGA) are also acknowledged.

We present a comparative density functional theory study of the electronic and optical properties of graphene and borophene with an adsorbed ionic liquid. The Dirac cones of these two-dimensional nanostructures are not affected by the presence of the ionic liquid close to these sheets, not even in the borophene one in which a very small charge transfer to the ionic liquid anion is detected. However, Bader analysis and charge density calculations showed that the polarization of the ionic liquid induces a redistribution of the electric charge in both sheets as a consequence of the electromagnetic interaction between the anion and cation of the ionic liquid and the electrons on the two-dimensional materials, the effect being notably stronger in graphene than in borophene. Our calculations reveal that several changes take place in the dielectric constant and electron energy loss spectra, including shifts and damping of plasmon bands, related to electrostatically induced changes in the adsorbent surface electron charge distributions and to plasmon loss channels associated to excitations of electrons in the energy levels of the adsorbed ionic liquid species close to the Fermi level of the surface material. While only minor changes are registered in borophene plasmon spectra and in the IR and visible regions of the graphene spectra, important changes in the graphene ultraviolet C and X-ray spectra are registered due to the existence of IL electronic energy levels close to the Fermi level of graphene that are absent in borophene.

The synthesis of highly functionalized bicyclic and cyclic β-amino acids from β-nitrosugars is reported. Specifically, our strategy for the synthesis of polyhydroxylated cyclopentane β-amino acids via the intramolecular C-alkylation of 6-nitro-2-O-triflates of furanosides has been applied to the preparation of the first two examples of a novel class of bicyclic β-amino acids and a novel cyclopentene β-amino acid. Also, our Henry reaction mediated strategy for the synthesis of polyhydroxylated cyclohexane β-amino acids has been extended to a divergent, stereoselective synthesis of new polysubstituted cyclohexane and cyclopentane β-amino acids.

The first example of an ammonium derivative that causes a specific modification of the active site of type I dehydroquinase (DHQ1), a dehydratase enzyme that is a promising target for antivirulence drug discovery, is described. The resolution at 1.35 Å of the crystal structure of DHQ1 from Salmonella typhi chemically modified by this ammonium derivative revealed that the ligand is covalently attached to the essential Lys170 through the formation of an amine. The detection by mass spectroscopy of the reaction intermediates, in conjunction with the results of molecular dynamics simulations, allowed us to explain the inhibition mechanism and the experimentally observed differences between S. typhi and Staphylococcus aureus enzymes. The results presented here reveal that the replacement of Phe225 in St-DHQ1 by Tyr214 in Sa-DHQ1 and its hydrogen bonding interaction with the conserved water molecule observed in several crystal structures protects the amino adduct against further dehydration/aromatization reactions. In contrast, for the St-DHQ1 enzyme, the carboxylate group of Asp114, with the assistance of this water molecule, would trigger the formation of a Schiff base that can undergo further dehydration reactions until full aromatization of the cyclohexane ring is achieved. Moreover, in vitro antivirulence studies showed that the reported compound is able to reduce the ability of Salmonella Enteritidis to kill A459 respiratory cells. These studies have identified a good scaffold for the design of irreversible inhibitors that can be used as drugs and has opened up new opportunities for the development of novel antivirulence agents by targeting the DHQ1 enzyme Financial support from the Spanish Ministry of Science and Innovation (SAF2013-42899-R), Xunta de Galicia (GRC2013-041), and the European Regional Development Fund (ERDF) is gratefully acknowledged. E.L. thanks the Xunta de Galicia for his postdoctoral fellowship. A.B. thanks the Miguel Servet Programme ISCIII-FEDER (CP13/00226) and the ISCIIIGeneral Subdirection of Assesment and Promotion of the Research (PI14/00059) for financial support SI

The integration of units of differing natures which are found in different parts of some multilevel personality models is one of the most thought-provoking paths in contemporary research. In the field of compulsive buying, little is known about the interrelationships between the comparative and stable units such as personality traits (basic tendencies or Level I units) and goals (a kind of middle-level unit) which are more related to motivational processes and intentions governing peoplersquo;s behavior.Self-reporting measures of compulsive buying, Big Five personality traits, and extrinsic life aspirations were administered to a general population sample consisting of 2,159 participants aged 15 to 65 (48.1% males; Mage= 35.4, SD= 13.24).Our results confirmed statistically significant associations with compulsive buying for the traits as well as the extrinsic goals. Furthermore, an important relationship between both levels in personalityndash; traits vs . extrinsic life aspirationsndash; was found. Finally, extrinsic life aspirations (specially, image, popularity, and conformity) contribute to the potentiation of the prediction of compulsive buying beyond the Five Factor Model.Current findings emphasize the advisability of considering both levels in personality, traits and middle-level units like life aspirations, not only in the prediction of compulsive buying, but also as potential targets for preventive and treatment programs.

The structural and dynamical properties of bulk mixtures of long-chained primary and secondary alcohols (propanol, butanol, and 2-pentanol) with protic ionic liquids (ethylammonium and butylammonium nitrate) were studied by means of molecular dynamics simulations and small angle X-ray scattering (SAXS). Changes in the structure with the alcohol concentration and with the alkyl chain length of the alcohol moieties were found, showing variations in the radial distribution function and in the number of hydrogen bonds in the bulk liquids. Moreover, the structural behaviour of the studied mixtures is further clarified with the spatial distribution functions. The global picture in the local scale is in good agreement with the nanostructured solvation paradigm [T. Mendez-Morales et al. Phys. Chem. B 118, 761 (2014)], according to which alcohols are accommodated into the hydrogen bonds’ network of the ionic liquid instead of forming clusters in the bulk. Indeed, our study reveals that the alcohol molecules are placed with their polar heads at the interfaces between polar and nonpolar nanodomains in the ionic liquid, with their alkyl chains inside the nonpolar organic nanodomains. The influence of alcohol chain length in the single-particle dynamics of the mixtures is also reported calculating the velocity autocorrelation function and vibrational densities of states of the different species in the ionic liquid-alcohol mixtures, and a weak caging effect for the ethylammonium cations independent of the chain size of the alcohols was found. However, the SAXS data collected for the studied mixtures show an excess of the scattering intensities which indicates that there are also some structural heterogeneities at the nanoscale.

Solvation in mixtures of 1-ethyl-3-methylimidazolium acetate ionic liquid with water in a molar concentration of 5% is studied by means of atomistic molecular dynamics (MD) simulations. We employed a spherical coarse-grained parameterization to describe a model solute and we performed MD simulations with positively charged, negatively charged and neutral model spheres and compare the results with those previously reported in pure ionic liquids. Our study reveals that water does not significantly perturb the structure of the electric double layer neither the orientation of ions in the neighborhood of the solute particle. Although water does not seem to play any significant role in the solvation of neutral solutes, there is an excess of water in the first and second ionic solvation shell of both charged solutes, respectively. We also studied the correlation between the electric field around the negatively charged model solute and the orientation of the dipole moment of water molecules, finding that, although the dynamic properties of water molecules are almost unaltered in the presence of the solutes, and the ionic cage around the central solutes is only slightly affected upon water addition, the mobility of the spheres is drastically enhanced.

In order to investigate the effect of defects on the structure of an electrode on the electric double layer of ionic-liquid-based electrolytes, we perform classical molecular dynamic simulations on mixtures of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) and lithium tetrafluoroborate (LiBF4) near charged graphene electrodes with different percentages of single defect vacancies, assuming planarity of the defected graphene, as follows from our density-functional theory calculations. Defects on the electrode's surface modify the surface charge density at the innermost layer of the electrochemical interface, which allows studying the structure of the electric double layer at a constant density of ions without changing either the voltage or the electrolyte composition. Indeed, we report that the presence of defects on the graphene electrodes can induce structural transitions in the innermost layer of the electric double layer. This result is supported by a thorough analysis of the structural properties of the layer and its energy landscape, particularly showing that there is a direct correlation between this defect-induced layer structure and the adsorption of the salt cations at the electrode, which is of utmost importance for the usage of these novel electrolytic mixtures in actual electrochemical devices.

In the search for alternative non‐metabolizable inducers in the l ‐rhamnose promoter system, the synthesis of fifteen 6‐deoxyhexoses from l ‐rhamnose demonstrates the value of synergy between biotechnology and chemistry. The readily available 2,3‐acetonide of rhamnonolactone allows inversion of configuration at C4 and/or C5 of rhamnose to give 6‐deoxy‐d ‐allose, 6‐deoxy‐d ‐gulose and 6‐deoxy‐l ‐talose. Highly crystalline 3,5‐benzylidene rhamnonolactone gives easy access to l ‐quinovose (6‐deoxy‐l ‐glucose), l ‐olivose and rhamnose analogue with C2 azido, amino and acetamido substituents. Electrophilic fluorination of rhamnal gives a mixture of 2‐deoxy‐2‐fluoro‐l ‐rhamnose and 2‐deoxy‐2‐fluoro‐l ‐quinovose. Biotechnology provides access to 6‐deoxy‐l ‐altrose and 1‐deoxy‐l ‐fructose.

The first stereocontrolled synthesis of (3R,4R,5R,6S)-2,2-bis-(hydroxymethyl)azepane-3,4,5,6-tetraol is described herein. The method involves a novel double Henry reaction of the 3,5-di-O-benzyl-6-deoxy-1,2-O-isopropylidene-6-nitro-α-d-glucofuranose with formaldehyde followed by a reductive ring closure to give the first branched 1,6-dideoxy-1,6-heptitol described. © 2008 Elsevier Ltd. All rights reserved.

This work describes the behaviour of water molecules in 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid under nanoconfinement between graphene sheets. By means of molecular dynamics simulations, an adsorption of water molecules at the graphene surface is studied. A depletion of water molecules in the vicinity of the neutral and negatively charged graphene surfaces and their adsorption at the positively charged surface are observed in line with the preferential hydration of the ionic liquid anions. The findings are appropriately described using a two-level statistical model. The confinement effect on the structure and dynamics of the mixtures is thoroughly analyzed using the density and the potential of mean force profiles, as well as by the vibrational densities of states of water molecules near the graphene surface. The orientation of water molecules and the water-induced structural transitions in the layer closest to the graphene surface are also discussed., Comment: 14 pages, 7 figures, to appear in Journal of Physics: Condensed Matter

Enoyl-acyl carrier protein reductase (ENR; the product of the fabI gene) is an important enzyme that is involved in the type II fatty-acid-synthesis pathway of bacteria, plants, apicomplexan protozoa and mitochondria. Harmful pathogens such as Mycobacterium tuberculosis and Plasmodium falciparum use the type II fatty-acid-synthesis system, but not mammals or fungi, which contain a type I fatty-acid-synthesis pathway consisting of one or two multifunctional enzymes. For this reason, specific inhibitors of ENR are attractive antibiotic candidates. Triclosan, a broad-range antibacterial agent, binds to ENR, inhibiting fatty-acid synthesis. As humans do not have an ENR enzyme, they are not affected. Here, high-resolution structures of Thermus thermophilus (Tth) ENR in the apo form, bound to NAD(+) and bound to NAD(+) plus triclosan are reported. Differences from and similarities to other known ENR structures are reported; in general, the structures are very similar. The cofactor-binding site is also very similar to those of other ENRs and, as reported for other species, triclosan leads to greater ordering of the loop that covers the cofactor-binding site, which, together with the presence of triclosan itself, presumably provides tight binding of the dinucleotide, preventing cycling of the cofactor. Differences between the structures of Tth ENR and other ENRs are the presence of an additional β-sheet at the N-terminus and a larger number of salt bridges and side-chain hydrogen bonds. These features may be related to the high thermal stability of Tth ENR.

The main objective of this study is analyze the inter-relationships between the main stressors posing difficulties for school coexistence (students’ disruptive behavior, the teachers’ perception of a lack of social support and conflict), different personal variables (Type A behavior pattern, optimism, hardiness) and burnout. Furthermore, personal variables will be tested to see whether they mediate the influence of the different sources of stress analyzed in burnout. From the results obtained, using a sample of 1537 secondary education teachers, the covariation between the different sets of variables analyzed is not only confirmed but also significant support is given for the mediation hypothesis (stressors would have an indirect influence on burnout through personal variables). Another interesting finding is the need to include in the resulting model a direct effect between the students’ disruptive behavior and the teacher’s burnout experience. In short, the resulting path confirms the personal variables analyzed as a necessary filter in the analysis of the stressors-burnout link, while at the same time integrating the direct effect that students’ disruptive behavior has on teacher’s occupational malaise. .

This study examines not only the role of students‟ disruptive be haviour and/or attitudes but also the difficulties perceived by teachers in managing conflicts as a function of the different sociodemographic and occupational variables (gender, age, professional experience, teaching cycle). The results obtained from a sample consisting in 1386 ESO teachers allow us to conclude that both types of stressors validly discriminate as a function of sociodemographic and occupational variables. Specifically, the stress associated to students‟ disruptive behaviour and to the difficulties faced by teachers in managing conflict has a greater incidence on female teachers, on second cycle teachers and on intermediate stages in the profession. If these findings are corroborated by further research, it would be important to design prevention and/or intervention programmes that are sensitive to these risk factors.

En este trabajo se examina, en función de distintas variables sociodemográficas y ocupacionales (sexo, edad, experiencia profesional, ciclo de docencia), no sólo el papel de las conductas y/o actitudes problemáticas de los alumnos, sino también las dificultades percibidas por los profesores en el manejo de conflictos. Los resultados obtenidos, a partir de una muestra de 1.386 docentes de ESO, permiten concluir que ambos tipos de estresores diferencian válidamente en función de las variables sociodemográficas y ocupacionales. Concretamente, el estrés asociado a los problemas de comportamiento de los alumnos y a las dificultades del docente en el manejo de conflictos, incide en mayor medida en las profesoras, en los docentes de segundo ciclo y en aquellas etapas intermedias de la profesión. En definitiva, si estos hallazgos se ratifican en futuras investigaciones, se trataría de diseñar programas preventivos y/o de intervención que sean sensibles a estos factores de riesgo.Palabras clave: Estrés, profesores, conductas problema alumnos, manejo conflictos. This study examines not only the role of students’ disruptive behaviour and/or attitudes but also the difficulties perceived by teachers in managing conflicts as a function of the different sociodemographic and occupational variables (gender, age, professional experience, teaching cycle). The results obtained from a sample consisting in 1386 ESO teachers allow us to conclude that both types of stressors validly discriminate as a function of sociodemographic and occupational variables. Specifically, the stress associated to students’ disruptive behaviour and to the difficulties faced by teachers in managing conflict has a greater incidence on female teachers, on second cycle teachers and on intermediate stages in the profession. If these findings are corroborated by further research, it would be important to design prevention and/or intervention programmes that are sensitive to these risk factors.Key words: Stress, teachers, students’ disruptive behaviour, conflict management.

A novel promising strategy for the transformation of nitrosugars into branched pyrrolidines, based on double Henry reaction with formaldehyde followed by reductive ring closure, allowed the first enantiospecific synthesis of a 4-C-hydroxymethyl branched derivative of the well-known glycosidase inhibitor 1,4-dideoxy-1,4-imino-pentanol. This strategy also afforded a new route to some other interesting derivatives, such as N-hydroxy, N-propyloxy, and imino derivatives, a new kind of compounds with promising biological properties. [reaction: see text].

The irreversible inhibition of type I dehydroquinase (DHQ1), the third enzyme of the shikimic acid pathway, is investigated by structural, biochemical and computational studies. Two epoxides, which are mimetics of the natural substrate, were designed as irreversible inhibitors of the DHQ1 enzyme and to study the binding requirements of the linkage to the enzyme. The epoxide with the S configuration caused the covalent modification of the protein whereas no reaction was obtained with its epimer. The first crystal structure of DHQ1 from Salmonella typhi covalently modified by the S epoxide, which is reported at 1.4 Å, revealed that the modified ligand is surprisingly covalently attached to the essential Lys170 by the formation of a stable Schiff base. The experimental and molecular dynamics simulation studies reported here highlight the huge importance of the conformation of the C3 carbon of the ligand for covalent linkage to this type of aldolase I enzyme, revealed the key role played by the essential His143 as a Lewis acid in this process and show the need for a neatly closed active site for catalysis Financial support from the Spanish Ministry of Science and Innovation (SAF2013-42899-R), Xunta de Galicia (GRC2013-041) and the European Regional Development Fund (ERDF) is gratefully acknowledged. LT, AP and MM thank the Spanish Ministry of Education for their respective FPU fellowships. EL and JMO thank and the Xunta de Galicia for their respective postdoctoral fellowships SI

A stereoselective synthesis of two complex 1,2-dialkyl-2-amino-1-ethanols [(5S,6S)-6-amino-2,8-dimethylnonan-5-ol and (5S,6S)-6-amino-7-cyclohexyl-2- methylheptan-5-ol] is described from 5-azido-3,5,6-trideoxy-6-isopropyl-L-idose and 5-azido-3,5,6-trideoxy-6-cyclohexyl-Lidose respectively. ©ARKAT USA, Inc.

This paper focuses on the description and analysis of the distribution of sectoral employment over regions in Spain from 1985 to 1989, using a combination of shift-share analysis and location elasticities. We find that new tendencies have appeared in the evolution of Spanish employment, which have been maintained for the whole period 1985–89. We also find that the growth in Spanish employment is located in the Mediterranean area, and is closely related to the Services sector (especially Tourism) and to a modern and productive Agriculture, which is very different from that of the rest of Spain.

Structural and computational studies to explore the WAT1 binding pocket in the structure-based design of inhibitors against the type II dehydroquinase (DHQ2) enzyme are reported. The crystal structures of DHQ2 from M. tuberculosis in complex with four of the reported compounds are described. The electrostatic interaction observed between the guanidinium group of the essential arginine and the carboxylate group of one of the inhibitors in the reported crystal structures supports the recently suggested role of this arginine as the residue that triggers the release of the product from the active site. The results of the structural and molecular dynamics simulation studies revealed that the inhibitory potency is favored by promoting interactions with WAT1 and the residues located within this pocket and, more importantly, by avoiding situations where the ligands occupy the WAT1 binding pocket. The new insights can be used to advantage in the structure-based design of inhibitors Financial support from the Spanish Ministry of Science and Innovation (Grant SAF2010-15076) and the Xunta de Galicia (Grant GRC2013/041) is gratefully acknowledged. B.B. and A.P. thank the Spanish Ministry of Education for their respective FPU fellowships. A.S. thanks the Spanish Ministry of Economy and Competitiveness for her FPI fellowship. J.M.O. thanks the Xunta de Galicia for a Plan I2C postdoctoral fellowship SI

Structural, biochemical and computational studies to study substrate binding and the role of the conserved residues of the DHQ1 (type I dehydroquinase) enzyme active site are reported in the present paper. The crystal structure of DHQ1 from Salmonella typhi in complex with (2R)-2-methyl-3-dehydroquinic acid, a substrate analogue, was solved at 1.5 Å. The present study reveals a previously unknown key role for conserved Glu, Phe and Met and Gln, Pro and Ala residues, with the latter three being located in the flexible substrate-covering loop. Glu was shown to be responsible for the folding of this loop and for the dramatic reduction of its flexibility, which triggers active site closure. Glu46 was found to be key in bringing the substrate close to the lysine/histidine catalytic pocket to initiate catalysis. The present study could be useful in the rational design of inhibitors of this challenging and recognized target for the development of novel herbicides and antimicrobial agents This work was supported by the Spanish Ministry of Science and Innovation (grant number SAF2010-15076) and via FPU fellowships to M.M. and A.P., the Xunta de Galicia (grant number GRC2013/041) and via postdoctoral fellowships to E.L. and J.M.O., and by the European Regional Development Fund (ERDF) SI

In Alzheimer's disease, amyloid-β (Aβ) peptides aggregate into extracellular fibrillar deposits. Although these deposits may not be the prime cause of the neurodegeneration that characterizes this disease, inhibition or dissolution of amyloid fibril formation by Aβ peptides is likely to affect its development. ThT fluorescence measurements and AFM images showed that the natural antibiotic gramicidin S significantly inhibited Aβ amyloid formation in vitro and could dissolve amyloids that had formed in the absence of the antibiotic. In silico docking suggested that gramicidin S, a cyclic decapeptide that adopts a β-sheet conformation, binds to the Aβ peptide hairpin-stacked fibril through β-sheet interactions. This may explain why gramicidin S reduces fibril formation. Analogues of gramicidin S were also tested. An analogue with a potency that was four-times higher than that of the natural product was identified.

The structural changes caused by the substitution of the aromatic moiety in (2S)-2-benzyl-3-dehydroquinic acids and its epimers in C2 by electron-withdrawing or electron-donating groups in type II dehydroquinase enzyme from M. tuberculosis and H. pylori has been investigated by structural and computational studies. Both compounds are reversible competitive inhibitors of this enzyme, which is essential in these pathogenic bacteria. The crystal structures of M. tuberculosis and H. pylori in complex with (2S)-2-(4-methoxy)benzyl- and (2S)-2-perfluorobenzyl-3-dehydroquinic acids have been solved at 2.0, 2.3, 2.0, and 1.9 Å, respectively. The crystal structure of M. tuberculosis in complex with (2R)-2-(benzothiophen-5-yl)methyl-3-dehydroquinic acid is also reported at 1.55 Å. These crystal structures reveal key differences in the conformation of the flexible loop of the two enzymes, a difference that depends on the presence of electron-withdrawing or electron-donating groups in the aromatic moiety of the inhibitors. This loop closes over the active site after substrate binding, and its flexibility is essential for the function of the enzyme. These differences have also been investigated by molecular dynamics simulations in an effort to understand the significant inhibition potency differences observed between some of these compounds and also to obtain more information about the possible movements of the loop. These computational studies have also allowed us to identify key structural factors of the H. pylori loop that could explain its reduced flexibility in comparison to the M. tuberculosis loop, specifically by the formation of a key salt bridge between the side chains of residues Asp18 and Arg20 Financial support from the Xunta de Galicia (10PXIB2200122PR and GRC2010/12) and the Spanish Ministry of Science and Innovation (SAF2010-15076 to CGB and BFU2008-01588/BMC to M.J.vR.) is gratefully acknowledged. L.T., A.P., and V.F.V.P. thank the Spanish Ministry of Science and Innovation for FPU fellowships and the Portuguese Fundaca̧o para a Ciencia e a Tecnologia for an FCT fellowship, respectively. J.M.O. thanks the Xunta de Galicia and Spanish Ministry of Science and Innovation for “Ángeles Alvariño” and “José Castillejo” fellowships, respectively SI

Shikimate kinase (SK) is an essential enzyme in several pathogenic bacteria and does not have any counterpart in human cells, thus making it an attractive target for the development of new antibiotics. The key interactions of the substrate and product binding and the enzyme movements that are essential for catalytic turnover of the Mycobacterium tuberculosis shikimate kinase enzyme (Mt-SK) have been investigated by structural and computational studies. Based on these studies several substrate analogs were designed and assayed. The crystal structure of Mt-SK in complex with ADP and one of the most potent inhibitors has been solved at 2.15 Å. These studies reveal that the fixation of the diaxial conformation of the C4 and C5 hydroxyl groups recognized by the enzyme or the replacement of the C3 hydroxyl group in the natural substrate by an amino group is a promising strategy for inhibition because it causes a dramatic reduction of the flexibility of the LID and shikimic acid binding domains. Molecular dynamics simulation studies showed that the product is expelled from the active site by three arginines (Arg117, Arg136, and Arg58). This finding represents a previously unknown key role of these conserved residues. These studies highlight the key role of the shikimic acid binding domain in the catalysis and provide guidance for future inhibitor designs Financial support from ́ the Spanish Ministry of Economy and Competitiveness (SAF2010-15076 to CGB and BFU2011-24843 to M.J.vR.) and the Xunta de Galicia (10PXIB2200122PR and GRC2010/ 12) is gratefully acknowledged. B.B. thanks the Spanish Ministry of Education for her FPU fellowship. V.P. and C.G.D. thank the Spanish Ministry of Economy and Competitiveness for their respective FPI fellowships. J.M.O. thanks the Xunta de Galicia for a Plan I2C postdoctoral fellowship SI

15 pags, 9 figs, One goal of the CASP community wide experiment on the critical assessment of techniques for protein structure prediction is to identify the current state of the art in protein structure prediction and modeling. A fundamental principle of CASP is blind prediction on a set of relevant protein targets, that is, the participating computational methods are tested on a common set of experimental target proteins, for which the experimental structures are not known at the time of modeling. Therefore, the CASP experiment would not have been possible without broad support of the experimental protein structural biology community. In this article, several experimental groups discuss the structures of the proteins which they provided as prediction targets for CASP9, highlighting structural and functional peculiarities of these structures: the long tail fiber protein gp37 from bacteriophage T4, the cyclic GMP-dependent protein kinase Iβ dimerization/docking domain, the ectodomain of the JTB (jumping translocation breakpoint) transmembrane receptor, Autotaxin in complex with an inhibitor, the DNA-binding J-binding protein 1 domain essential for biosynthesis and maintenance of DNA base-J (β-D-glucosyl-hydroxymethyluracil) in Trypanosoma and Leishmania, an so far uncharacterized 73 residue domain from Ruminococcus gnavus with a fold typical for PDZ-like domains, a domain from the phycobilisome core-membrane linker phycobiliprotein ApcE from Synechocystis, the heat shock protein 90 activators PFC0360w and PFC0270w from Plasmodium falciparum, and 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae. © 2011 Wiley-Liss, Inc., Grant sponsor: Spanish Ministry of Education and Science; Grant number: BFU2008-01588; Grant sponsor: European Commission; Grant number: NMP4-CT-2006-033256; Grant sponsor: Spanish Ministry of Education and Science (José Castillejo fellowship); Grant sponsor: Xunta de Galicia (Angeles Alvariño fellowship); Grant sponsor: National Institutes of Health; Grant numbers: K22-CA124517 (D.E.C.); R01-GM090161 (C.K.) GM074942; GM094585; Grant sponsor: U. S. Department of Energy, Office of Biological and Environmental Research; Grant number: DE-AC02-06CH11357 (to A.J.); Grant sponsor: Foundation for Polish Science (to K.M.); Grant sponsor: NSF; Grant number: DBI 0829586.

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et al., The cyclic decapeptide gramicidin S (GS) was used as a model for the evaluation of four turn mimetics. For this purpose, one of the D-Phe-Pro two-residue turn motifs in the rigid cyclic β-hairp0in structure of GS was replaced with morpholine amino acids (MAA 2-5), differing in stereochemistry and length of the side-chain. The conformational properties of the thus obtained GS analogues (6-9) was assessed by using NMR spectroscopy and X-ray crystallography, and correlated with their biological properties (antimicrobial and hemolytic activity). We show that compound 8, containing the dipeptide isostere trans-MAA 4, has an apparent high structural resemblance with GS and that its antibacterial activity against a panel of Gram positive and -negative bacterial strains is better than the derivatives 6, 7 and 9. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA., Este trabajo ha sido financiado por una beca del Leiden Institute of Chemistry y por la subvención BFU2008-01588/BMC del Ministerio español de Ciencia e Innovación. José M. Otero ha sido apoyado económicamente por un contratro “Angeles Alvariño” de la Xunta de Galicia.

Bacteriophages are the most numerous organisms in the biosphere. In spite of their biological significance and the spectrum of potential applications, little high-resolution structural detail is available on their receptor-binding fibers. Here we present the crystal structure of the receptor-binding tip of the bacteriophage T4 long tail fiber, which is highly homologous to the tip of the bacteriophage lambda side tail fibers. This structure reveals an unusual elongated sixstranded antiparallel beta-strand needle domain containing seven iron ions coordinated by histidine residues arranged colinearly along the core of the biological unit. At the end of the tip, the three chains intertwine forming a broader head domain, which contains the putative receptor interaction site. The structure reveals a previously unknown beta-structured fibrous fold, provides insights into the remarkable stability of the fiber, and suggests a framework for mutations to expand or modulate receptor-binding specificity., This research was sponsored by Grant BFU2008-01588 (to M.J.v.R.), a José Castillejo fellowship (J.M.O.), and a Formacion del Profesorado Universitario Fellowship (C.G.D.) from the Spanish Ministry of Education and Science. This work was also supported by the European Commission under Contract NMP4-CT-2006-033256 and by the Xunta de Galicia via an Angeles Alvariño fellowship (J.M.O.).

The shikimic acid pathway is essential to many pathogens but absent in mammals. Enzymes in its pathway are therefore appropriate targets for the development of novel antibiotics. Dehydroquinase is the third enzyme of the pathway, catalyzing the reversible dehydratation of 3-dehydroquinic acid to form 3-dehydroshikimic acid. Here we present the synthesis of novel inhibitors with high affinity for Helicobacter pylori type II dehydroquinase and efficient inhibition characteristics. The structure of Helicobacter pylori type II dehydroquinase in complex with the most potent inhibitor shows that the aromatic functional group interacts with the catalytic Tyr22 by π-stacking, expelling the Arg17 side chain, which is essential for catalysis, from the active site. The structure therefore explains the favorable properties of the inhibitor and will aid in design of improved antibiotics. © 2009 American Chemical Society., This work was supported by the Spanish Ministry of Science and Innovation (under Projects SAF2007-63533 to C.G.B., BFU2005-02974/BMC and BFU2008-01588/ BMC to M.J.v.R.), CSIC (Grant 488IE7 to M.J.v.R.), and the Xunta de Galicia (Grants PGIDT07PXIB209080PR and GRC2006/132 to C.G.B.). V.F.V.P., J.M.O., L.T., and P.G.-C. thank the Portuguese Fundaçao para a Ciência e a Tecnología for a FCT fellowship, the Xunta de Galicia for a “Angeles Alvariño” contract, and the Spanish Ministry of Science and Innovation for FPU fellowships, respectively. Data collection at EMBL/DESY was supported by the European Community FP6 Research Infrastructure Action “Structuring the European Research Area”, Contract No. RII3/CT/2004/5060008.

et al., The cyclic cationic antimicrobial peptide gramicidin S (GS) is an effective topical antibacterial agent that is toxic for human red blood cells (hemolysis). Herein, we present a series of amphiphilic derivatives of GS with either two or four positive charges and characteristics ranging between very polar and very hydrophobic. Screening of this series of peptide derivatives identified a compound that combines effective antibacterial activity with virtually no toxicity within the same concentration range. This peptide acts against both Gram-negative and Gram-positive bacteria, including several MRSA strains, and represents an interesting lead for the development of a broadly applicable antibiotic. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., Trabajo financiado por el Ministerio de España de Educación y Ciencia (número de concesión: BFU2008–01588) y Xunta de Galicia.