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101.
Lisa Giachini Giulia Veronesi Francesco Francia Giovanni Venturoli Federico Boscherini 《Journal of synchrotron radiation》2010,17(1):41-52
In the present work a data analysis approach, based on XAFS data, is proposed for the identification of most probable binding motifs of unknown mononuclear zinc sites in metalloproteins. This approach combines multiple‐scattering EXAFS analysis performed within the rigid‐body refinement scheme, non‐muffin‐tin ab initio XANES simulations, average structural information on amino acids and metal binding clusters provided by the Protein Data Bank, and Debye–Waller factor calculations based on density functional theory. The efficiency of the method is tested by using three reference zinc proteins for which the local structure around the metal is already known from protein crystallography. To show the applicability of the present analysis to structures not deposited in the Protein Data Bank, the XAFS spectra of six mononuclear zinc binding sites present in diverse membrane proteins, for which we have previously proposed the coordinating amino acids by applying a similar approach, is also reported. By comparing the Zn K‐edge XAFS features exhibited by these proteins with those pertaining to the reference structures, key spectral characteristics, related to specific binding motifs, are observed. These case studies exemplify the combined data analysis proposed and further support its validity. 相似文献
102.
103.
Yron Joseph Yabut Manaig Silvia Sandrini Sara Panseri Gabriella Tedeschi Josep M. Folch Armand Snchez Giovanni Savoini Alessandro Agazzi 《Molecules (Basel, Switzerland)》2022,27(9)
Elevated omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids (PUFAs) ratios in swine diets can potentially impose a higher risk of inflammatory and metabolic diseases in swine. A low ratio between the two omega PUFAs has beneficial effects on sows’ and piglets’ production performance and immunity status. At present, there are few studies on how sow nutrition directly affects the protein and fat deposition in suckling piglets. Two groups of sows were fed diets with high or low n-6/n-3 polyunsaturated ratios of 13:1 (SOY) and 4:1 (LIN), respectively, during gestation and lactation. Longissimus dorsi muscle and adipose tissue from newborn piglets, nourished only with sow’s milk, were subjected to fatty acid profiling by gas chromatography–mass spectrometry (GC-MS) and to proteomics assays based on nano-liquid chromatography coupled to high-resolution tandem mass spectrometry (nLC-HRMS). Fatty acid profiles on both muscle and adipose tissues resembled the magnitude of the differences between fatty acid across diets. Proteomic analysis revealed overabundance of 4 muscle and 11 adipose tissue proteins in SOY compared to LIN in both piglet tissues. The detected overabundance of haptoglobin, an acute-phase protein, and the stimulation of protein-coding genes and proteins related to the innate immune response and acute inflammatory response could be associated with the pro-inflammatory role of n-6 PUFAs. 相似文献
104.
Tarek Benameur Giulia Giacomucci Maria Antonietta Panaro Melania Ruggiero Teresa Trotta Vincenzo Monda Ilaria Pizzolorusso Dario Domenico Lofrumento Chiara Porro Giovanni Messina 《Molecules (Basel, Switzerland)》2022,27(1)
Curcumin, the dietary polyphenol isolated from Curcuma longa (turmeric), is commonly used as an herb and spice worldwide. Because of its bio-pharmacological effects curcumin is also called “spice of life”, in fact it is recognized that curcumin possesses important proprieties such as anti-oxidant, anti-inflammatory, anti-microbial, antiproliferative, anti-tumoral, and anti-aging. Neurodegenerative diseases such as Alzheimer’s Diseases, Parkinson’s Diseases, and Multiple Sclerosis are a group of diseases characterized by a progressive loss of brain structure and function due to neuronal death; at present there is no effective treatment to cure these diseases. The protective effect of curcumin against some neurodegenerative diseases has been proven by in vivo and in vitro studies. The current review highlights the latest findings on the neuroprotective effects of curcumin, its bioavailability, its mechanism of action and its possible application for the prevention or treatment of neurodegenerative disorders. 相似文献
105.
Giovanni Fronza Claudio Fuganti Piero Grasselli Stefano Servi 《Tetrahedron letters》1985,26(40):4961-4964
Baker's yeast mediated reduction of the α-acetoxy ketones (1)–(3) proceeds with high enantio- and stereoselectivity to give the carbinols (4)–(6), easily converted into the masked chiral deoxy sugars (12)–(14), from which {=D}- and {=L}-deoxysugars have been obtained. 相似文献
106.
Anna Bernardi Silvia Cardani Cesare Gennari Giovanni Poli Carlo Scolastico 《Tetrahedron letters》1985,26(52):6509-6512
MgBr2 mediated addition of Methyl α-methylthio propionate silylketene acetal to α and α,β-alkoxy aldehydes is highly 3,4 -selective (18:1). -α- methylene-β- hydroxy-?-alkoxy esters (6) and (8) are synthesized. 相似文献
107.
108.
Antonino Corsaro Ugo Chiacchio Giancarlo Perrini Pierluigi Caramella Giovanni Purrello 《Journal of heterocyclic chemistry》1985,22(3):797-799
Cycloadditions of nitrile oxides to N-mono and unsubstituted β-aminocinnamonitriles are remarkably affected by the hydrogen acceptor ability of the solvent. Addition to C ? N bond predominates in non and weak hydrogen bond acceptor solvents because of the assistance of favourable hydrogen bonding effects. In strong hydrogen bond acceptor solvents the assistance is fully relieved and the regular addition to C ? C bond becomes prevalent. 相似文献
109.
An automated procedure for correcting the interference due to mixing the reagents in the determination of ATP by a bioluminescent
technique is described. The measurements were performed by an in-house interfaced PC photometer. An automated procedure based
on a robust regression method and outliers detection was applied to exclude the time of the mixing of the reagents from the
global time of reaction. In fact the mixing of the reagents is responsible of the poor analytical precision (RSD%>25) and
low sensitivity (limit of detection≈2×10-8 mol/l). By this procedure, the precision (RSD%<7) and sensitivity (limit of detection≈8×10-10 mol/l) were improved. The method was applied to the determination of ATP in marine sediments and good recovery within 90–108%
was obtained. For non-polluted samples the measurement can be carried out by direct comparison with standard solutions. The
standard addition procedure is recommended for polluted samples.
Received: 25 April 1996/Revised: 28 June 1996/Accepted: 3 July 1996 相似文献
110.
Dr. Maria Petrosino Dr. Francesco Stellato Prof. Roberta Chiaraluce Prof. Valerio Consalvi Dr. Giovanni La Penna Dr. Alessandra Pasquo Dr. Olivier Proux Prof. Giancarlo Rossi Prof. Silvia Morante 《ChemistryOpen》2021,10(11):1133-1141
We present in this work a first X-ray Absorption Spectroscopy study of the interactions of Zn with human BST2/tetherin and SARS-CoV-2 orf7a proteins as well as with some of their complexes. The analysis of the XANES region of the measured spectra shows that Zn binds to BST2, as well as to orf7a, thus resulting in the formation of BST2-orf7a complexes. This structural information confirms the the conjecture, recently put forward by some of the present Authors, according to which the accessory orf7a (and possibly also orf8) viral protein are capable of interfering with the BST2 antiviral activity. Our explanation for this behavior is that, when BST2 gets in contact with Zn bound to the orf7a Cys15 ligand, it has the ability of displacing the metal owing to the creation of a new disulfide bridge across the two proteins. The formation of this BST2-orf7a complex destabilizes BST2 dimerization, thus impairing the antiviral activity of the latter. 相似文献