di¤raction and x ray absorption spectroscopy at synchrotron radiation sources
Báo cáo Y học: The role of zinc in the methylation of the coenzyme M thiol group in methanol:coenzyme M methyltransferase from Methanosarcina barkeri New insights from X-ray absorption spectroscopy doc
Ngày tải lên :
17/03/2014, 23:20
... coordinated by S and (N/O) ligands MtaA and MtbA are only 40% sequence identical [22] but they share the putative HXCXnC zinc binding motif [15] The latter nding indicates that zinc coordination ... & Dau, H (1998) Structure and orientation of the oxygen-evolving manganese complex of green algae and higher plants investigated by X- ray absorption linear dichroism spectroscopy on oriented photosystem ... 1), immediately suggesting the presence of three (N/O)-ligands and one sulfur ligand Fixing the number of zinc ligands to the nearest integer values (i.e and for (N/O) and sulfur ligands, respectively)...
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Báo cáo khoa học: Structural function of C-terminal amidation of endomorphin Conformational comparison ofl-selective endomorphin-2 with its C-terminal free acid, studied by 1 H-NMR spectroscopy, molecular calculation, and X-ray crystallography pot
Ngày tải lên :
30/03/2014, 20:20
... 164 x, y,z x +1,y,z x +1,y,z 1 -x, y +1 ⁄ 2,-z x, y,z x, y,z x, y,z x, y,z x- 1,y,z 1 -x, y-1 ⁄ 2,1-z x, y,z x, y +1,z x, y +1,z x, y-1,z x, y-1,z x, y,z 1 -x, y-1 ⁄ 2,1-z x, y,z 1 -x, y +1 ⁄ 2,-z x, y +1,z x, y,z x, y-1,z ... solvent, that is, neutral form (in dimethyl sulfoxide and TFE) and monocationic form (in water and DPC micelles) for EM2, and zwitterionic form (in dimethyl sulfoxide, TFE, water, DPC micelles) and ... open and folded conformational features, except for population ratios, are not significantly different between EM2 and EM2OH The conformation–activity relationship of EM2 and EM2OH suggests that...
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Tài liệu Characterization of the Polymorphic Behavior of an Organic Compound Using a Dynamic Thermal and X-ray Powder Diffraction Technique pptx
Ngày tải lên :
14/02/2014, 03:20
... at 52% and 100% relative humidity (RH) indicated that Form I formed a heptahydrate at typical laboratory temperatures and quickly became anhydrous above approximately 60–80 °C in a dry atmosphere ... for 18 h, indicated that Form III forms a hexahydrate The TGA results are shown in Figure 11 and indicate that mol of water evolve below approximately 100 °C, and the last mole of water evolves ... anhydrous Form V A heat of approximately 10 J/g was observed Form V subsequently melted with an onset of approximately 245 °C and a peak at approximately 256 °C XRPD data from DSC/XRPD analysis are...
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Tài liệu Báo cáo khoa học: Destabilization of psychrotrophic RNase HI in a localized fashion as revealed by mutational and X-ray crystallographic analyses pdf
Ngày tải lên :
18/02/2014, 13:20
... thermal denaturation at Tm were calculated by van’t Hoff analysis X- Ray diffraction data sets of the 6·-RNase HI crystal were collected at 100 K using synchrotron radiation at the BL44XU station in ... the protein, and a and b represent the a helix and b strand, respectively The side-chains of the mutated and parent amino acid residues at the six mutation sites are shown D39 ⁄ G39 and M76 ⁄ V76 ... Helices and b strands are indicated by bars helices, and around Gly128 in a loop between the aV helix and bE strand The shifts around Gly17 and Asn18 are probably a result of fluctuations rather...
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Báo cáo khoa học: Determination of thioxylo-oligosaccharide binding to family 11 xylanases using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry and X-ray crystallography pot
Ngày tải lên :
07/03/2014, 17:20
... complex are summarized in Table Atomic co-ordinates for the crystal structures of TRX I, TRX II, CTX, and CTXS-Xyl5-Me complex can be found Table X- ray diffraction measurement and renement statistics ... thioxylo-oligosaccharide inhibitors to CTX without distortion to the expected 2,5B conformation [75] Experimental procedures Protein expression and purication Native, DNA-encoded TRX I and TRX II xylanases (Swiss-Prot ... al ă Thioxylo-oligosaccharide binding to xylanases Fig MS titration curves for TRX I (5 lM), TRX II (10 lM) and CTX (10 lM) with S-Xyl5-Me, S-Xyl4-Me and S-Xyl3-Me (initial concentrations of...
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fragment based drug discovery and x-ray crystallography
Ngày tải lên :
29/05/2014, 23:54
... use of X- ray crystallography for fragment screening, ix x Preface and describe some of the computational developments developed at Astex that have allowed the rapid generation of protein-ligand ... drugs that can form aggregates at high concentrations that they were aggregators, and that the medicinal chemistry effort had inadvertently optimized for aggregation [26] It is hard to understate ... Crystallography 39 a X X NH X = C,N,O X = C,N O O O O N H O X Y Y X N N NH C=O C O C C NH Y X b C=O NH C C O NH C X Y Y N X H N H N O N Pyrrole Imidazole Furan Benzene N N H N H N N N Pyridine Cyclohexane Pyrimidine...
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Báo cáo hóa học: "Valence band offset of InN/BaTiO3 heterojunction measured by X-ray photoelectron spectroscopy" pot
Ngày tải lên :
21/06/2014, 04:20
... participated in the experimental analysis XL carried out the growth and optimization of indium nitride films SY participated in the experimental measurement WZ participated in its design and coordination ... one located at 457.12 ± 0.03 eV is attributed to the Ti emitters within the BTO substrate, which have six bonds to oxygen atoms The other one shifting by ~2 eV to a lower binding energy is attributed ... maximum; VBO: valence band offset; XPS: X- ray photoelectron spectroscopy Authors’ contributions CJ carried out the experimental analysis and drafted the manuscript YC carried out the experimental design...
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Báo cáo hóa học: " Valence band offset of wurtzite InN/SrTiO3 heterojunction measured by x-ray photoelectron spectroscopy" ppt
Ngày tải lên :
21/06/2014, 05:20
... approximately treated as completely relaxed and this approximation should not introduce much error in our result In addition, InN always exhibits obvious electron accumulation at its surface and ... Oxidation study of polycrystalline InN film using in situ X- ray scattering and X- ray photoemission spectroscopy Thin Solid Films 2007, 515:4691 Lee IJ, Kim JY, Shin HJ, Kim HK: Near-edge x- ray ... due to contamination by oxygen during the growth process The ratio of In-N peak intensity to the oxygen-related peak indicates that only a small quantity of oxygen contamination exists in our samples...
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Báo cáo hóa học: " Determination of InN/Diamond Heterojunction Band Offset by X-ray Photoelectron Spectroscopy" docx
Ngày tải lên :
21/06/2014, 11:20
... The XPS measurements were performed on a PHI Quantera SXM instrument with Al Ka (energy 1486.6 eV) as the X- ray radiation source, which had been carefully calibrated utilizing work function and ... measured by XPS A type-I band alignment with a valence band offset of ΔEv ~ 0.39 ± 0.08 eV and conduction band offset of ΔEc ~ 4.42 eV was obtained The accurate determination of the band alignment ... side The unrelexed Koopaman’s state produced by removal of a core electron is not an eigenstate and is projected onto “screened” and “unscreened” final eigenstates [21], the latter corresponding...
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Báo cáo hóa học: " Measurement of w-InN/h-BN Heterojunction Band Offsets by X-Ray Photoemission Spectroscopy" docx
Ngày tải lên :
21/06/2014, 17:20
... 5:1340–1343 1341 XPS measurement was performed on PHI Quantera SXM instrument with Al Ka (hm = 1486.6 eV) as the X- ray radiation source and the angle between the X- ray source and the detector ... charge compensation All XPS spectra were calibrated by the C 1-s peak at 284.8 eV from contamination to compensate the charge effect Results and Discussion The VBO can be calculated according ... positions of peak locked at 443.71, 444.54, and 445.45 eV, as shown in Fig 1a The binding energy of 443.71 and 444.54 eV associated with screened final state and the unscreened final states, respectively...
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Báo cáo vật lý: "ATTENUATION STUDIES ON DRY AND HYDRATED CROSS-LINKED HYDROPHILIC COPOLYMER MATERIALS AT 8.02 TO 28.43 keV USING X-RAY FLUORESCENT SOURCES" ppt
Ngày tải lên :
07/08/2014, 14:20
... industrial Xray machine It was water-cooled and could produce X- radiation continuously The tube assembly type was a Comet ceramic X- ray tube assembly MXR160/0.4–3.0 The tube generator was a Pantak ... fluorescent X- rays with effective energies of 8.02, 17.41, 22.08 and 25.16 keV, respectively The unattenuated and the attenuated XRF beam from the molybdenum target in ED4C sample (fully hydrated in ... lower X- ray source Collimator mm dia Sample θ 90O Detector Collimators mm dia Target Figure 1: Typical arrangement of the XRF set-up at the City University 4500 4000 Kα 3500 Unattenuated Attenuated...
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Báo cáo sinh học: "Developmental time at which spontaneous, X-ray-induced and EMS-induced recessive lethal mutations become effective in Drosophila melanogaster" potx
Ngày tải lên :
14/08/2014, 20:20
... study is that lethal mutations extracted from natural populations become effective considerably later on the average than X- ray- and ENTS-induced lethal mutations Since natural mutations can ... for the X- ray- and EMS-induced lethals It is wells known that an acute irradiation with a high X- ray dose over a rather short time induces a high proportion of chromosomal aberrations that are ... irradiated with 000 rad in air Irradiation was administrated at a rate of 900 rad/min from an X- ray source (Mueller, Typ RT 100) operated at 10 kV, MA via a 10-cm tube with 1-mm Be filtration...
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Báo cáo y học: "Application of Small Angle X-ray Scattering (SAXS) for Differentiation between Normal and Cancerous Breast Tissue"
Ngày tải lên :
02/11/2012, 11:08
... results confirmed this expectation The peak position of fibrocystic change was close to that of carcinoma However, the t-test examination revealed that they could be separated statistically into two ... terminal ductules dilate, untwist, and unfold to produce a solitary locule that then enlarges as a cyst Understandably, fibrosis is often reported by pathologists in an attempt to explain clinical ... were positioned at the center of the scattering volume defined by the collimation geometry During the scatter measurements, the sample was rotated at constant speed to ensure that all parts of...
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Tài liệu Báo cáo khoa học: X-ray crystallographic and NMR studies of pantothenate synthetase provide insights into the mechanism of homotropic inhibition by pantoate docx
Ngày tải lên :
16/02/2014, 09:20
... Protein–ligand and water-mediated protein–ligand hydrogen bond interactions (broken lines) that stablize the pantoate molecules in site I and site II of nPS Oxygen atoms of pantoate and water are ... oxygen atoms of pantoate are shown in yellow and red, respectively The carbon and oxygen atoms of ATP are shown in red, the nitrogen atoms in blue, and the phosphorus atoms in orange (see text ... substrates This strongly suggests that binding of pantoate and ATP preserves the dimer symmetry in solution In an effort to unambiguously identify and understand the nature of binding of pantoate at...
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Tài liệu Báo cáo khoa học: Molecular determinants of ligand specificity in family 11 carbohydrate binding modules – an NMR, X-ray crystallography and computational chemistry approach doc
Ngày tải lên :
18/02/2014, 17:20
... focused our attention on those methods that allow us to obtain information on the bound carbohydrate 2526 The identification and mapping of the ligand epitopes (i.e atoms of the ligand that are closer ... the identification of the atoms of the ligand that are closer to the protein when the complex is formed The ligands cellobiose, cellotetraose and cellohexaose were studied Results and Discussion ... and identify which atoms of the ligand and of CtCBM11 interact preferentially Calculations were performed with cellobiose, cellotetraose and cellohexaose carbohydrates Moreover, for each ligand,...
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Tài liệu Báo cáo Y học: The solution structure and activation of visual arrestin studied by small-angle X-ray scattering pot
Ngày tải lên :
22/02/2014, 07:20
... NaCl, pH 7.5, and concentrated to approximately 0.13 mM by ultrafiltration; the ultrafiltrate was retained and used for buffer subtraction during the SAXS experiments Following concentration, the ... appraisal, evaluations and display for synchrotron radiation experiments: hardware and software Nucl Instrum Methods A249, 399–407 21 Guinier, A & Fournet, G (1955) Small Angle Scattering of X- rays Wiley, ... molecular mass at low protein concentrations approaches that of a monomer, and increases with protein concentration to that of a dimer, with an equilibrium dissociation constant, Kd, of approximately...
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Báo cáo khoa học: The effect of replacing the axial methionine ligand with a lysine residue in cytochrome c-550 from Paracoccus versutus assessed by X-ray crystallography and unfolding ppt
Ngày tải lên :
07/03/2014, 17:20
... may be expected for this type of ligand interaction Substitution of the axial Met ligand with a Lys influences ligand dissociation and protein stability The latter point is illustrated at acidic ... (rt) and 138 (cc) water molecules and one heme group An X- ray dataset was collected for the wt protein ˚ from a single crystal at room temperature to 1.90 A resolution Structure determination ... Peroxidase activity of the M100K variant In the native state ferricyt c-550 is able to catalyse H2O2 reduction with concomitant oxidation of a reducing substrate albeit with an extremely low rate...
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Báo cáo khoa học: X-ray crystallography, CD and kinetic studies revealed the essence of the abnormal behaviors of the cytochrome b5 Phe35fiTyr mutant pdf
Ngày tải lên :
08/03/2014, 10:20
... to heat and urea did display several isosbestic points in the absorbance curves, and the denaturation curves really showed that the denaturation followed the two-state mechanism The denaturation ... in the oxidized state is 3.3 kJÆmol)1 more stable than the wild-type protein towards heat denaturation and is 4.3 kJÆmol)1 more stable in urea denaturation The CD spectra of heat denaturation also ... Thermal denaturation of wild-type cyt b5 and its Phe35fiTyr mutant show similar CD behavior A negative peak at 418 nm with strong intensity and a positive peak at 390 nm at room temperature are...
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Báo cáo Y học: Determinants of the inhibition of a Taiwan habu venom metalloproteinase by its endogenous inhibitors revealed by X-ray crystallography and synthetic inhibitor analogues pdf
Ngày tải lên :
08/03/2014, 23:20
... superfamily of metzincin which exhibits some typical structural features, such as the Met-turn and active-site consensus HExxHxxGxxH sequence [15–17] Some organisms and mammalian tissues recently ... R & Bode, W (1995) X- ray structures of human neutrophil collagenase complexed with peptide hydroxamate and peptide thiol inhibitors Implications for substrate binding and rational drug design ... Wat359 and Wat418, by two oxygens of the C-terminal carboxylic group of the inhibitor, which coordinate to the metal ion in an asymmetric bidentate manner (see Fig 2) His143 Ne2 and Wat416 are located...
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Báo cáo Y học: Boar salivary lipocalin Three-dimensional X-ray structure and androstenol/androstenone docking simulations pot
Ngày tải lên :
17/03/2014, 17:20
... the Protein Data Bank at RCSB (http://www.rcsb.org/pdb/) under entry G6 Docking experiment with androstenol and androstenone The previously identified natural ligands androstenol and androstenone ... ÔinÕ and ÔoutÕ for androstenone and androstenol, we have observed clashes between the steroid and the protein that could not be eliminated manually Therefore, we performed a careful and conservative ... representation The helix is in red, strands are blue and turns or coil are yellow The GlcNAc residue bound to Asn53 is in white ball -and- stick, and the serendipitous ligand, glycerol, in green ball -and- stick...
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