Search results for "biologia"
showing 10 items of 2476 documents
Genomic investigation of a legionellosis outbreak in a persistently colonized hotel
2016
Objectives: A long-lasting legionellosis outbreak was reported between November 2011 and July 2012 in a hotel in Calpe (Spain) affecting 44 patients including six deaths. Intensive epidemiological and microbiological investigations were performed in order to detect the reservoirs. Methods: Clinical and environmental samples were tested for the presence and genetic characterization of Legionella pneumophila. Six of the isolates were subjected to whole-genome sequencing. Results: Sequencing of 14 clinical and 260 environmental samples revealed sequence type (ST) 23 as the main responsible strain for the infections. This ST was found in the spa pool, from where it spread to other hotel public …
Use of autochthonous yeasts and bacteria in order to control Brettanomyces bruxellensis in wine
2017
Biocontrol strategies for the limitation of undesired microbial developments in foods and beverages represent a keystone toward the goal of more sustainable food systems. Brettanomyces bruxellensis is a wine spoilage microorganism that produces several compounds that are detrimental for the organoleptic quality of the wine, including some classes of volatile phenols. To control the proliferation of this yeast, sulfur dioxide is commonly employed, but the efficiency of this compound depends on the B. bruxellensis strain; and it is subject to wine composition and may induce the entrance in a viable, but nonculturable state of yeasts. Moreover, it can also elicit allergic reactions in humans. …
Rhodococcus aetherivorans BCP1 as cell factory for the production of intracellular tellurium nanorods under aerobic conditions
2016
Tellurite (TeO3 2−) is recognized as a toxic oxyanion to living organisms. However, mainly anaerobic or facultative-anaerobic microorganisms are able to tolerate and convert TeO3 2− into the less toxic and available form of elemental Tellurium (Te0), producing Te-deposits or Te-nanostructures. The use of TeO3 2−-reducing bacteria can lead to the decontamination of polluted environments and the development of “green-synthesis” methods for the production of nanomaterials. In this study, the tolerance and the consumption of TeO3 2− have been investigated, along with the production and characterization of Te-nanorods by Rhodococcus aetherivorans BCP1 grown under aerobic conditions. Aerobically …
Shelf life evaluation of fresh-cut red chicory subjected to different minimal processes
2018
Abstract Microbiological, chemical and physical parameters of minimally processed red chicory (Cichorium intybus L.) subjected to two different transformation processes were investigated. A classic ready-to-eat (RTE) process (P1) and a production without cutting (P2) were monitored during refrigerated (4 °C) storage (15 d). Total mesophilic microorganisms, total psychrotrophic microorganisms and pseudomonads were detected at the highest cell densities in all samples. Presumptive Pseudomonas population dominated the cultivable microbial community of RTE red chicory and were characterized genetically. Twenty-two randomly amplified polymorphic DNA (RAPD) types were investigated by 16S rRNA gen…
Biological insertion of computationally designed short transmembrane segments
2016
The great majority of helical membrane proteins are inserted co-translationally into the ER membrane through a continuous ribosome-translocon channel. The efficiency of membrane insertion depends on transmembrane (TM) helix amino acid composition, the helix length and the position of the amino acids within the helix. In this work, we conducted a computational analysis of the composition and location of amino acids in transmembrane helices found in membrane proteins of known structure to obtain an extensive set of designed polypeptide segments with naturally occurring amino acid distributions. Then, using an in vitro translation system in the presence of biological membranes, we experimental…
Revisiting the pH-gated conformational switch on the activities of HisKA-family histidine kinases
2020
13 páginas, 6 figuras, 3 tablas
Rescuing the CFTR protein function: Introducing 1,3,4-oxadiazoles as translational readthrough inducing drugs.
2018
Nonsense mutations in the CFTR gene prematurely terminate translation of the CFTR mRNA leading to the production of a truncated protein that lacks normal function causing a more severe form of the cystic fibrosis (CF) disease. About 10% of patients affected by CF show a nonsense mutation. A potential treatment of this alteration is to promote translational readthrough of premature termination codons (PTCs) by Translational Readthrough Inducing Drugs (TRIDs) such as PTC124. In this context we aimed to compare the activity of PTC124 with analogues differing in the heteroatoms position in the central heterocyclic core. By a validated protocol consisting of computational screening, synthesis an…
On the (un)coupling of the chromophore, tongue interactions, and overall conformation in a bacterial phytochrome
2018
Phytochromes are photoreceptors in plants, fungi, and various microorganisms and cycle between metastable red light-absorbing (Pr) and far-red light-absorbing (Pfr) states. Their light responses are thought to follow a conserved structural mechanism that is triggered by isomerization of the chromophore. Downstream structural changes involve refolding of the so-called tongue extension of the phytochrome-specific GAF-related (PHY) domain of the photoreceptor. The tongue is connected to the chromophore by conserved DIP and PRXSF motifs and a conserved tyrosine, but the role of these residues in signal transduction is not clear. Here, we examine the tongue interactions and their interplay with …
In silico discovery of substituted pyrido[2,3-d]pyrimidines and pentamidine-like compounds with biological activity in myotonic dystrophy models
2016
Myotonic dystrophy type 1 (DM1) is a rare multisystemic disorder associated with an expansion of CUG repeats in mutant DMPK (dystrophia myotonica protein kinase) transcripts; the main effect of these expansions is the induction of pre-mRNA splicing defects by sequestering muscleblind-like family proteins (e.g. MBNL1). Disruption of the CUG repeats and the MBNL1 protein complex has been established as the best therapeutic approach for DM1, hence two main strategies have been proposed: targeted degradation of mutant DMPK transcripts and the development of CUG-binding molecules that prevent MBNL1 sequestration. Herein, suitable CUG-binding small molecules were selected using in silico approach…
Caffeine boosts Ataluren's readthrough activity
2019
Abstract The readthrough of nonsense mutations by small molecules like Ataluren is considered a novel therapeutic approach to overcome the gene defect in several genetic diseases as cystic fibrosis (CF). This pharmacological approach suppresses translation termination at premature termination codons (PTCs readthrough) thus restoring the expression of a functional protein. However, readthrough might be limited by the nonsense-mediated mRNA decay (NMD), a cell process that reduces the amount/level of PTCs containing mRNAs. Here we investigate the combined action of Ataluren and caffeine to enhance the readthrough of PTCs. IB3.1 CF cells with a nonsense mutation were treated with caffeine to a…