Use of plant extracts to block bacterial biofilm formation

Proceedings of the I Congress PIIISA celebrado en la Estación Experimental del Zaidín (Granada), en mayo de 2013.We live surrounded by bacteria; in fact, in only one gram of soil we can find millions of bacterial cells. Our body houses more than 1014 bacteria. Even though some of these microorganisms can cause us problems, such as caries, actually most of them help in the proper functioning of our organism. Generally, bacteria coexist setting up communities associated to solid superficies, this is to which we refer as biofilms, that serve as a survival strategy. This type of formation cause serious sanitary problems for both humans and animals. Nowadays, chemical or natural compounds able to block this formation are looked for. In this project, we have set out how to use extracts of different plants with the purpose of testing their effects against biofilms of two bacterial species: Escherichia coli and Pseudomonas putida.This work was supported in part by grant BFU2010-17946 from the Plan Nacional de I+D+I.Peer reviewe

Genomic analysis reveals the major driving forces of bacterial life in the rhizosphere

A global analysis of Pseudomonas putida gene expression performed during the interaction with maize roots revealed how a bacterial population adjusts its genetic program to the specific conditions of this lifestyle

Prejudicialidad en procedimientos con cláusula suelo respecto de la acción colectiva.

Se ha planteado por la asociación de consumidores, ADICAE, acciones colectivas solicitando la nulidad de las cláusulas suelo, procedimiento 177/2015 Juzgado de lo Mercantil de Madrid. De forma simultánea se han ejercitado acciones individuales reclamando la nulidad de las citadas clausulas y la devolución de las cantidades abonadas en exceso. En el caso objeto de dictamen, se ejercita un procedimiento individual contra mi cliente, Caja de Ahorros Aragón, en el cual la Entidad deberá alegar además de los motivos de fondo oportunos, las excepciones procesales de prejudicialidad y litispendecia. Alegando que el procedimiento de acciones colectivas ejercitado es un antecedente necesario del procedimiento individual y que éste debe paralizarse hasta que aquel termine por sentencia firme

Characterization of a phage-like pyocin from the plant growth-promoting rhizobacterium Pseudomonas fluorescens SF4c

R-type and F-type pyocins are high-molecular-mass bacteriocins produced by Pseudomonas aeruginosa that resemble bacteriophage tails. They contain no head structures and no DNA, and are used as defence systems. In this report, we show that Pseudomonas fluorescens SF4c, a strain isolated from the wheat rhizosphere, produces a high-molecular-mass bacteriocin which inhibits the growth of closely related bacteria. A mutant deficient in production of this antimicrobial compound was obtained by transposon mutagenesis. Sequence analysis revealed that the transposon had disrupted a gene that we have named ptm, since it is homologous to that encoding phage tape-measure protein in P. fluorescens Pf0-1, a gene belonging to a prophage similar to phage-like pyocin from P. aeruginosa PAO1. In addition, we have identified genes from the SF4c pyocin cluster that encode a lytic system and regulatory genes. We constructed a nonpolar ptm mutant of P. fluorescens SF4c. Heterologous complementation of this mutation restored the production of bacteriocin. Real-time PCR was used to analyse the expression of pyocin under different stress conditions. Bacteriocin was upregulated by mitomycin C, UV light and hydrogen peroxide, and was downregulated by saline stress. This report constitutes, to our knowledge, the first genetic characterization of a phage tail-like bacteriocin in a rhizosphere Pseudomonas strain. © 2012 Society for General Microbiology.Fil: Fischer, Sonia Elizabeth. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; España. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones Agrobiotecnológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Agrobiotecnológicas; ArgentinaFil: Godino, Agustina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Quesada, José Miguel. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Cordero Gabrielli, Paula Verónica. Universidad Nacional de Río Cuarto; Argentina. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; ArgentinaFil: Jofré, Edgardo. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto; ArgentinaFil: Mori, Gladys Beatriz. Universidad Nacional de Río Cuarto; ArgentinaFil: Espinosa Urgel, Manuel. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; Españ

Problemas de localización de bases de ambulancias. Una aplicación en la provincia de Teruel

En este trabajo se describen varios problemas de localización y se aplican algunos de ellos a la ubicación de bases de ambulancias en la provincia de Teruel.<br /

On‐Surface Interchain Coupling and Skeletal Rearrangement of Indenofluorene Polymers

On-surface synthesis serves as a powerful approach to construct π-conjugated carbon nanostructures that are not accessible by conventional wet chemistry. Nevertheless, this method has been limited by the types and numbers of available on-surface transformations. While the majority of successful cases exploit thermally triggered dehalogenative carbon–carbon coupling and cyclodehydrogenation, rearrangement of appropriate functional moieties has received limited research attention. Here, the unprecedented interchain coupling and thermally induced skeleton rearrangement are described of (dihydro)indeno[2,1-b]fluorene (IF) polymers on an Au(111) surface under ultrahigh vacuum conditions, leading to different ladder polymers as well as fully fused graphene nanoribbon segments containing pentagonal and heptagonal rings. Au-coordinated nanoribbons are also observed. All structures are unambiguously characterized by high-resolution scanning probe microscopy. The current results provide an avenue to fabricating a wider variety of π-conjugated polymers and carbon nanostructures comprising nonhexagonal rings as well as rarely explored organometallic nanoribbons.journal articl

Characterization of the bacteriocins and the PrtR regulator in a plant-associated Pseudomonas strain

The emergence of antibiotic resistant bacterial strains demands the development of new antimicrobial agents. In the last decades, bacteriocins have gained significant interest due to their potential application as biopreservatives in the food industry and as therapeutic agents in medicine. Recent studies project the use of these antimicrobials in agriculture as biocontrol agents. The characterization of bacteriocins and their genetic regulation, however, have been scarcely studied in plant-associated bacteria. In this report, an in-silico and proteomic analysis was performed to identify the bacteriocins produced by Pseudomonas fluorescens SF4c. More than one functional bacteriocin was detected in this strain (S-type bacteriocins and phage-tail-like bacteriocins [tailocins]). It is known that the regulator PrtR represses bacteriocin production in P. aeruginosa under normal condition. However, the mechanism for tailocin regulation remains unknown in plant-associated pseudomonads. In this work, an orthologue of the prtR of P. aeruginosa was identified in the SF4c-tailocin cluster and a prtR null mutant constructed. The expression and production of tailocins was abolished in this mutant; thus evidencing that, unlike P. aeruginosa, PrtR is a positive regulator of tailocins expression in P. fluorescens.Fil: Fernandez, Maricruz. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones Agrobiotecnológicas - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Agrobiotecnológicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Godino, Agustina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Principe, Analia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: López Ramírez, Viviana. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones Agrobiotecnológicas - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Agrobiotecnológicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Quesada, José Miguel. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Rigo, Virginia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Espinosa-Urgel, Manuel. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Morales, Gustavo Marcelo. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Fischer, Sonia Elizabeth. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones Agrobiotecnológicas - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Agrobiotecnológicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; Argentin

Electrically Tunable Reactivity of Substrate-Supported Cobalt Oxide Nanocrystals

[EN] First-row transition metal oxides are promising materials for catalyzing the oxygen evolution reaction. Surface sensitive techniques provide a unique perspective allowing the study of the structure, adsorption sites, and reactivity of catalysts at the atomic scale, which furnishes rationalization and improves the design of highly efficient catalytic materials. Here, a scanning probe microscopy study complemented by density functional theory on the structural and electronic properties of CoO nanoislands grown on Au(111) is reported. Two distinct phases are observed: The most extended displays a Moiré pattern (α-region), while the less abundant is 1Co:1Au coincidental (β-region). As a result of the surface registry, in the β-region the oxide adlayer is compressed by 9%, increasing the unoccupied local density of states and enhancing the selective water adsorption at low temperature through a cobalt inversion mechanism. Tip-induced voltage pulses irreversibly transform α- into β-regions, thus opening avenues to modify the structure and reactivity of transition metal oxides by external stimuli like electric fields.This work was supported by the European Union under the H2020 FET-PROACT A-LEAF (Artificial-Leaf ) project (Grant Agreement No. 732840). Barcelona Supercomputing Center. Grant Number: QS-2019-3-002

On-Surface Thermal Stability of a Graphenic Structure Incorporating a Tropone Moiety

On-surface synthesis, complementary to wet chemistry, has been demonstrated to be a valid approach for the synthesis of tailored graphenic nanostructures with atomic precision. Among the different existing strategies used to tune the optoelectronic and magnetic properties of these nanostructures, the introduction of non-hexagonal rings inducing out-of-plane distortions is a promising pathway that has been scarcely explored on surfaces. Here, we demonstrate that non-hexagonal rings, in the form of tropone (cycloheptatrienone) moieties, are thermally transformed into phenyl or cyclopentadienone moieties upon an unprecedented surface-mediated retro–Buchner-type reaction involving a decarbonylation or an intramolecular rearrangement of the CO unit, respectivel