Search results for "subtil"
showing 10 items of 108 documents
Gene Cloning, Transcriptional Analysis, Purification, and Characterization of Phenolic Acid Decarboxylase from Bacillus subtilis
1998
Phenolic acids, also called substituted cinnamic acids, are important lignin-related aromatic acids and natural constituents of plant cell walls. These acids (particularly ferulic, p-coumaric, and caffeic acids) bind the complex lignin polymer to the hemicellulose and cellulose in plants (1) or are generally esterified with tartaric acid (for example, in grape must, wine, and cider) and can be released as free acids during wine making by some cinnamoyl esterase activities (9). Most often, free phenolic acids are metabolized by different microorganisms into 4-vinyl derivatives and then are eventually reduced into 4-ethyl derivatives (5, 6). Some of these volatile phenols, particularly vinyl …
Hybrid Quantum Mechanics/Molecular Mechanics Simulations with Two-Dimensional Interpolated Corrections: Application to Enzymatic Processes
2006
Hybrid quantum mechanics/molecular mechanics (QM/MM) techniques are widely used to study chemical reactions in large systems. Because of the computational cost associated with the high dimensionality of these systems, the quantum description is usually restricted to low-level methods, such as semiempirical Hamiltonians. In some cases, the description obtained at this computational level is quite poor and corrections must be considered. We here propose a simple but efficient way to include higher-level corrections to be used in potential energy surface explorations and in the calculation of potentials of mean force. We evaluate a correction energy term as the difference between a high-level …
Purification and Characterization of <I>Bacillus cereus</I> Protease Suitable for Detergent Industry
2005
An extracellular alkaline protease from an alkalophilic bacterium, Bacillus cereus, was produced in a large amount by the method of extractive fermentation. The protease is thermostable, pH tolerant, and compatible with commercial laundry detergents. The protease purified and characterized in this study was found to be superior to endogenous protease already present in commercial laundry detergents. The enzyme was purified to homogeneity by ammonium sulfate precipitation, concentration by ultrafiltration, anion-exchange chromatography, and gel filtration. The purified enzyme had a specific activity of 3256.05 U/mg and was found to be a monomeric protein with a molecular mass of 28 and 31 kD…
Tumor necrosis factor-alpha converting enzyme is processed by proprotein-convertases to its mature form which is degraded upon phorbol ester stimulat…
2003
Tumor necrosis factor-alpha converting enzyme (TACE or ADAM17) is a member of the ADAM (a disintegrin and metalloproteinase) family of type I membrane proteins and mediates the ectodomain shedding of various membrane-anchored signaling and adhesion proteins. TACE is synthesized as an inactive zymogen, which is subsequently proteolytically processed to the catalytically active form. We have identified the proprotein-convertases PC7 and furin to be involved in maturation of TACE. This maturation is negatively influenced by the phorbol ester phorbol-12-myristate-13-acetate (PMA), which decreases the cellular amount of the mature form of TACE in PMA-treated HEK293 and SH-SY5Y cells. Furthermore…
Uso del tonometro e rischio infettivo ; valutazione dell'efficacia di differenziali tipi di disinfettanti.
2006
Obiettivo: valutare e confrontare l’efficacia dei più comuni tipi di disinfettanti per la disinfezione dei coni tonometrici e trarre alcune indicazioni sulla applicabilità alla realtà clinico-diagnostica in campo oftalmologico. Materiali e metodi: coni tonometrici monouso sterili, previamente contaminati con ceppi standard di Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa e Candida albicans sono stati testati, dopo semplice detersione o disinfezione con acqua ossigenata al 3%, benzalconio cloruro allo 0.5%, Minuten wipes (Alpro® ), Pantasept® allo 0.5% secondo le linee guida del CDC di Atlanta. Risultati: la semplice detersione è stata inefficace contro tutte le specie tes…
Study of Bacillus subtilis spore's : characterication of stuctures implied in its resistance
2013
The bacterial spore is a multilayer microbial form which is extremely resistant to environmental perturbations. This resistance is especially due to its unique structure which is particularly compact and weakly permeable. This work aims to identify and characterize the spore structures involved in these properties. Overall investigation methods, such as NMR and fluorescence anisotropy, have shown that the cortex of Bacillus subtilis spores is modified by temperature for level similar to that of the activation of germination. This will result in changes to the access to the inner membrane. A tool at the spore’s scale, the fluorescence lifetime imaging microscopy (FLIM) in conjunction with th…
Sensing of O 2 and nitrate by bacteria: alternative strategies for transcriptional regulation of nitrate respiration by O 2 and nitrate
2020
Many bacteria are able to use O2 and nitrate as alternative electron acceptors for respiration. Strategies for regulation in response to O2 and nitrate can vary considerably. In the paradigmatic system of E. coli (and γ-proteobacteria), regulation by O2 and nitrate is established by the O2 -sensor FNR and the two-component system NarX-NarL (for nitrate regulation). Expression of narGHJI is regulated by the binding of FNR and NarL to the promoter. A similar strategy by individual regulation in response to O2 and nitrate is verified in many genera by the use of various types of regulators. Otherwise, in the soil bacteria Bacillus subtilis (Firmicutes) and Streptomyces (Actinobacteria), nitrat…
Transcytosis of Bacillus subtilis extracellular vesicles through an in vitro intestinal epithelial cell model
2020
Bacterial EVs have been related to inter-kingdom communication between probiotic/pathogenic bacteria and their hosts. Our aim was to investigate the transcytosis process of B. subtilis EVs using an in vitro intestinal epithelial cell model. In this study, using Confocal Laser Scanning Microscopy, we report that uptake and internalization of CFSE-labeled B. subtilis EVs (115 nm ± 27 nm) by Caco-2 cells are time-dependent. To study the transcytosis process we used a transwell system and EVs were quantified in the lower chamber by Fluorescence and Nanoparticle Tracking Analysis measurements. Intact EVs are transported across a polarized cell monolayer at 60–120 min and increased after 240 min …
Antimicrobial Effects Of The Ethanolic Extracts And Essential Oils Of Tanacetum Vulgare L From Romania
2015
Abstract This paper investigates the antimicrobial action of the extracts and essential oil of wildgrowing Tanacetum vulgare L on: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacilus subtilis, using the diffusion disc method. The essential oils but also the ethanolic extracts tested exhibited moderate action on Staphilococcus aureus and Bacillus subtilis and low action on E. coli and Pseudomonas aeruginosa. The moderate antimicrobial activity is related to the amount of some chemical components of the essential oil of T. vulgare flos. Thus, this paper presents also the quantitative and qualitative analysis of the essential oils of T. vulgare harvested from two differ…
Statin intolerance: new data and further options for treatment
2021
Purpose of review Hypercholesterolemia is a major risk factor for cardiovascular diseases. Administration of statins represents the cornerstone of the prevention and treatment of cardiovascular disease, with demonstrated long-term safety and efficacy. This review aims to revisit statin intolerance mechanisms, as well as to discuss new data and therapeutic options. Recent findings Although statins are well tolerated, myopathy and other adverse effects are a challenging problem, being the main reason for poor adherence to treatment and failure in lowering cardiovascular risk. Statin intolerance is the subject of ongoing research, as these drugs are widely used. There are alternative options o…