35 research outputs found
Estudio in vitro del efecto de los ácidos fenólicos naturales sobre el crecimiento y producción de aflatoxinas por Aspergillus parasiticus: abstract
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Mycoprev: elaboración de un código de buenas prácticas en la zona fronteriza España-Francia-Andorra como herramienta de prevención y control de micotoxinas en cereales: abstract
Publishe
Prevención y reducción de toxinas de Fusarium en cereales mediante el uso de ácidos fenólicos naturales: abstract
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Emergence of multiple EGFR extracellular mutations during cetuximab treatment in colorectal cancer
A comprehensive binding study illustrates ligand recognition in the periplasmic binding protein PotF
Periplasmic binding proteins PBPs are ubiquitous receptors in gram negative bacteria. They sense solutes and play key roles in nutrient uptake. Escherichia coli s putrescine receptor PotF has been reported to bind putrescine and spermidine. We reveal that several similar biogenic polyamines are recognized by PotF. Using isothermal titration calorimetry paired with X ray crystallography of the different complexes, we unveil PotF s binding modes in detail. The binding site for PBPs is located between two lobes that undergo a large conformational change upon ligand recognition. Hence, analyzing the influence of ligands on complex formation is crucial. Therefore, we solved crystal structures of an open and closed apo state and used them as a basis for molecular dynamics simulations. In addition, we accessed structural behavior in solution for all complexes by 1H 15N HSQC NMR spectroscopy. This combined analysis provides a robust framework for understanding ligand binding for future developments in drug design and protein engineerin
Identification and Analysis of Natural Building Blocks for Evolution-Guided Fragment-Based Protein Design
Natural evolution has generated an impressively diverse protein universe via duplication and recombination from a set of protein fragments that served as building blocks. The application of these concepts to the design of new proteins using subdomain-sized fragments from different folds has proven to be experimentally successful. To better understand how evolution has shaped our protein universe, we performed an all-against-all comparison of protein domains representing all naturally existing folds and identified conserved homologous protein fragments. Overall, we found more than 1000 protein fragments of various lengths among different folds through similarity network analysis. These fragments are present in very different protein environments and represent versatile building blocks for protein design. These data are available in our web server called F(old P)uzzle (fuzzle.uni-bayreuth.de), which allows to individually filter the dataset and create customized networks for folds of interest. We believe that our results serve as an invaluable resource for structural and evolutionary biologists and as raw material for the design of custom-made proteins
Estudio fitotóxico de los isómeros "E/Z" del herbicida alloxidim en trigo
Alloxydim is an herbicide marketed as the E-isomer applied at early stages of grass weeds. In the field, sunlight and temperature can induce the isomerization reaction of E-alloxydim to form the mixture of E and Z isomers. A bioassay has been performed to compare the herbicidal activity of E-alloxydim and its corresponding E/Z isomeric mixture in wheat plants. The IC50 values calculated from the root lengths of wheat for E-alloxydim and alloxydim mixture were 0.37 and 0.70 mg L-1, respectively. The Z isomer of alloxydim in the isomeric mixture has no phytotoxic effect on the wheat germination whereas E-alloxydim inhibited the seed germination at low concentrations (from 0.0 to 4.0 mg L-1).Aloxidim es un herbicida comercializado como el isómero E que se aplica en los estadios tempranos de las malas hierbas. En el campo, la luz solar y la temperatura pueden inducir las reacción de isomerización de E-aloxidim para formar la mezcla de los isómeros E y Z. Se ha llevado a cabo un bioensayo para comparar la actividad herbicida de E-aloxydim y su correspondiente mezcla de isómeros E/Z en trigo. Los valores de IC50 calculados a partir de la longitud de raÃz de trigo de E-aloxidim y la mezcla 0,37 y 0,70 mg L-1, respectivamente. El isómero Z-aloxidim en la mezcla isomérica no tiene efecto fitotóxico sobre la germinación de trigo, mientras que E- aloxidim inhibe la germinación de semillas a bajas concentraciones (de 0,0 a 4,0 mg L-1)
Reranking Docking Poses Using Molecular Simulations and Approximate Free Energy Methods
Fast and accurate identification
of active compounds is essential
for effective use of virtual screening workflows. Here, we have compared
the ligand-ranking efficiency of the linear interaction energy (LIE)
method against standard docking approaches. Using a trypsin set of
1549 compounds, we performed 12,250 molecular dynamics simulations.
The LIE method proved effective but did not yield results significantly
better than those obtained with docking codes. The entire database
of simulations is released