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101.
Peptide‐Based Fluorescent Probes for Deacetylase and Decrotonylase Activity: Toward a General Platform for Real‐Time Detection of Lysine Deacylation 下载免费PDF全文
Dr. Debra R. Rooker Yuliya Klyubka Dr. Ritika Gautam Prof. Dr. Elisa Tomat Prof. Dr. Daniela Buccella 《Chembiochem : a European journal of chemical biology》2018,19(5):496-504
Histone deacetylases regulate the acetylation levels of numerous proteins and play key roles in physiological processes and disease states. In addition to acetyl groups, deacetylases can remove other acyl modifications on lysines, the roles and regulation of which are far less understood. A peptide‐based fluorescent probe for single‐reagent, real‐time detection of deacetylase activity that can be readily adapted for probing broader lysine deacylation, including decrotonylation, is reported. Following cleavage of the lysine modification, the probe undergoes rapid intramolecular imine formation that results in marked optical changes, thus enabling convenient detection of deacylase activity with good statistical Z′ factors for both absorption and fluorescence modalities. The peptide‐based design offers broader isozyme scope than that of small‐molecule analogues, and is suitable for probing both metal‐ and nicotinamide adenine dinucleotide (NAD+)‐dependent deacetylases. With an effective sirtuin activity assay in hand, it is demonstrated that iron chelation by Sirtinol, a commonly employed sirtuin inhibitor, results in an enhancement in the inhibitory activity of the compound that may affect its performance in vivo. 相似文献
102.
Daniela T?uber Christian von Borczyskowski 《International journal of molecular sciences》2013,14(10):19506-19525
Single molecule (SM) methods are able to resolve structure related dynamics of guest molecules in liquid crystals (LC). Highly diluted small dye molecules on the one hand explore structure formation and LC dynamics, on the other hand they report about a distortion caused by the guest molecules. The anisotropic structure of LC materials is used to retrieve specific conformation related properties of larger guest molecules like conjugated polymers. This in particular sheds light on organization mechanisms within biological cells, where large molecules are found in nematic LC surroundings. This review gives a short overview related to the application of highly sensitive SM detection schemes in LC. 相似文献
103.
Justyna Chodkowska-Miszczuk Daniela Szymańska 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(1):117-123
The article aims to analyze the current state and determine the perspectives for oilseed rape production for energy purposes in Poland. According to the study, in recent years the oilseed rape area for energy purposes and the production of biocomponents and biofuels from oilseed rape have been on the rise in Poland. The considerable and spatially concentrated energy potential of oilseed rape in Poland is noted. It is indicated that the greatest energy potential of the oilseed rape production is the four neighboring voivodeships: Dolno?l?skie, Opolskie, Wielkopolskie, and Kujawsko-Pomorskie. 相似文献
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Alessandro Grandini Daniela Summa Stefania Costa Raissa Buzzi Elena Tamburini Gianni Sacchetti Alessandra Guerrini 《International journal of molecular sciences》2022,23(8)
Phytopathogenic fungi are among the main causes of productivity losses in agriculture. To date, synthetic chemical pesticides, such as hydroxyanilides, anilinopyrimidines and azole derivatives, represent the main treatment tools for crop plant defence. However, the large and uncontrolled use of these substances has evidenced several side effects, namely the resistance to treatments, environmental damage and human health risks. The general trend is to replace chemicals with natural molecules in order to reduce these side effects. Moreover, the valorisation of agri-food industry by-products through biotransformation processes represents a sustainable alternative to chemical synthesis in several sectors. This research is aimed at comparing the anti-phytopathogenic activity of waste bovine and porcine bile with secosteroids obtained by biotransformation of bile acids with Rhodococcus strains. The ultimate goal is to apply these natural products on food crops affected by phytopathogenic fungi. 相似文献
106.
Tíffany Marín Daniela Ortega Paula Montoya Oscar Arnache Jorge Calderón 《Journal of Applied Electrochemistry》2014,44(12):1401-1410
This paper shows how magnetic nanoparticles are produced by electrochemical synthesis using a low carbon steel bar as an anode and 100 mA cm?2 electric perturbations at room temperature. Two different kinds of salts, (CH3)4NCl and NaCl, were used to prepare the supporting electrolyte solutions. This allowed a comparison to be made between a surfactant and common salt, and allowed their influence on particle size to be analyzed. Additionally, mixtures of water and ethanol were added to the electrolyte solution in order to improve particle size distribution. The nanoparticle samples were characterized by X-ray diffraction, TEM, magnetization measurements, and Raman and Mössbauer spectroscopy. The results showed that after an optimized time of 10 min, the nanoparticles obtained in all the evaluated electrolytes were mainly magnetite (Fe3O4). The particles were between 8 and 10 nm in size. Depending on the nature of the electrolyte, the magnetite nanoparticles exhibited high purity and stoichiometry. The presence of ethanol in the electrolyte avoided particle agglomeration during the formation of magnetite. When the magnetic nanoparticles were exposed to an external magnetic field they showed superparamagnetic behavior and negligible coercivity. Such qualities are extremely useful for applications like ferrofluid precursors. 相似文献
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The purpose of the article is to provide some evidence on the interconnection between capital structure, R&D investment and ownership concentration using a unique panel data-set of Italian firms. We study the effect of R&D intensity on leverage for two groups of firms which are different in terms of their degree of ownership concentration. Our results suggest for Public Limited Companies, a nonlinear relationship between R&D intensity and leverage, with the latter first increasing and then decreasing. Interestingly, the same result is not found to hold true for Private Limited Companies, which are characterized by a more concentrated ownership. 相似文献
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The Netherlands is the most densely populated country of the European Union, which makes space very expensive. This leads to increasing complexity of the cities’ layout and other public spaces, together with a large number of people involved. Authorities would like to know whether new and innovative building designs ensure an appropriate level of safety of people in case of fire, before the accident happens, and to be prepared for the so-called “low probability–high consequences” accidents. Therefore, they need a tool to help them estimate the extent of a fire in a building, given any combination of possible conditions and any unexpected course of events during an emergency. This paper discusses the possibility of using Bayesian belief nets for this task. Using this approach, the people in charge can take decisions at different stages of the design process of a building regarding the location, the structure, the loading of the building, the types of fire protection systems inside the building, as well as the characteristics of the fire brigade that fights the possible fire. In the current study, usefulness of the approach is investigated using a small example. This will show the feasibility of the approach for the Netherlands situation and give authorities involved confidence that building a large comprehensive model would fulfil their needs for a support tool in the planning process. The effort to gather real data therefore was restricted as demonstration of fitness for purpose was the primary objective. 相似文献