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171.
172.
Eduardo Rezende Graminho Ronivaldo Rodrigues da Silva Tatiana Pereira de Freitas Cabral Eliane Candiani Arantes Nathalia Gonsales da Rosa Luiz Juliano Debora Noma Okamoto Lilian Caroline Gonçalves de Oliveira Marcia Yuri Kondo Maria Aparecida Juliano Hamilton Cabral 《Applied biochemistry and biotechnology》2013,169(1):201-214
The purpose of this work was to purify a protease from Penicillium waksmanii and to determine its biochemical characteristics and specificity. The extracellular protease isolated that was produced by P. waksmanii is a serine protease that is essential for the reproduction and growth of the fungus. The protease isolated showed 32 kDa, and has optimal activity at pH 8.0 and 35 °C towards the substrate Abz-KLRSSKQ-EDDnp. The protease is active in the presence of CaCl2, KCl, and BaCl, and partially inhibited by CuCl2, CoCl2 and totally inhibited by AlCl3 and LiCl. In the presence of 1 M urea, the protease remains 50 % active. The activity of the protease increases 60 % when it is exposed to 0.4 % nonionic surfactant-Triton X-100 and loses 10 % activity in the presence of 0.4 % Tween-80. Using fluorescence resonance energy transfer analysis, the protease showed the most specificity for the peptide Abz-KIRSSKQ-EDDnp with k cat/K m of 10,666 mM?1?s?1, followed by the peptide Abz-GLRSSKQ-EDDnp with a k cat/K m of 7,500 mM?1?s?1. Basic and acidic side chain-containing amino acids performed best at subsite S1. Subsites S2, S3, S′ 2, and S′ 1, S′ 3 showed a preference for binding for amino acids with hydrophobic and basic amino acid side chain, respectively. High values of k cat/K m were observed for the subsites S2, S3, and S′ 2. The sequence of the N-terminus (ANVVQSNVPSWGLARLSSKKTGTTDYTYD) showed high similarity to the fungi Penicillium citrinum and Penicillium chrysogenum, with 89 % of identity at the amino acid level. 相似文献
173.
Henri-Jean Cbistau Chantal Garcia Jumah Kadoura Eliane Torreilles 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):151-154
Abstract Metallated aminophosphonium ylids, diaza-diylids and azayldiid, are investigated as reagents for primary and secondary amines synthesis. 相似文献
174.
Henri-Jean Cristau Marie Fonte Eliane Torreilles Et Jacques Viala 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract Change in the regioselectivity of the addition of nucleophilic compounds YH (ROH, RSH, RNH2) on α -allenic ketones and esters can be achieved by using the triphenylphosphonio group as an umpolung agent1). In this way α, β-unsaturated ketones and esters 4 are obtained with heteroatomic substituents in the γ position. The Umpolung scheme of the activated allene 1 is charaterized by a functional vinylphosphonium salt 2 as a synthetic equivalent of the a4-synthon 3. 相似文献
175.
Among the methods described (1–4) to prepare β,γ-unsaturated ketones 2, Warren (4) recommends the Wittig-Horner procedure involving β-acetalated diphenylphosphinoxides reagents |scheme 1 (i)|. 相似文献
176.
Dulce Peris-Moreno Laura Cussonneau Lydie Combaret Ccile Polge Daniel Taillandier 《Molecules (Basel, Switzerland)》2021,26(2)
Skeletal muscle loss is a detrimental side-effect of numerous chronic diseases that dramatically increases mortality and morbidity. The alteration of protein homeostasis is generally due to increased protein breakdown while, protein synthesis may also be down-regulated. The ubiquitin proteasome system (UPS) is a master regulator of skeletal muscle that impacts muscle contractile properties and metabolism through multiple levers like signaling pathways, contractile apparatus degradation, etc. Among the different actors of the UPS, the E3 ubiquitin ligases specifically target key proteins for either degradation or activity modulation, thus controlling both pro-anabolic or pro-catabolic factors. The atrogenes MuRF1/TRIM63 and MAFbx/Atrogin-1 encode for key E3 ligases that target contractile proteins and key actors of protein synthesis respectively. However, several other E3 ligases are involved upstream in the atrophy program, from signal transduction control to modulation of energy balance. Controlling E3 ligases activity is thus a tempting approach for preserving muscle mass. While indirect modulation of E3 ligases may prove beneficial in some situations of muscle atrophy, some drugs directly inhibiting their activity have started to appear. This review summarizes the main signaling pathways involved in muscle atrophy and the E3 ligases implicated, but also the molecules potentially usable for future therapies. 相似文献
177.
The addition of equimolecular quantities of phosphonium salts to an aqueous sodium perborate solution (Na+ PB−) greatly enhances he efficiency of Na+ PB− as a reagene that destroys organophosphorus esters, such as p-nitrophenyldiethyl phosphate or ethyl p-nitrophenyl methylphosphonate. 相似文献
178.
179.
Bertrand Schmitt Eliane Alexandre Karim Boudjema Pierre J. Lutz 《Macromolecular Symposia》1995,93(1):117-124
Hydrogels were obtained by free-radical polymerization of bifunctional macromonomers. This reaction can be conducted in water solution or in organic solvent. The kp value is yet strongly depending on the solvent used. The properties of these networks will be compared to those of networks obtained by end-linking procedures. These materials were also used as a semi-permeable membrane in the conception of an artificial pancreas. 相似文献