Preparation,Crystallization, and Preliminary X-Ray Diffraction Study of Mutant Carboxypeptidase T Bearing the Hydrophilized Primary Specificity Pocket

Crystallography Reports - Crystals of mutant carboxypeptidase T from Thermoactinomyces vulgaris (CPT11QG)with amino acid substitutions L211Q, T262S, L254S, and A251S were grown by the hanging-drop...     

Sortases from a Probiotic Lactobacillus rhamnosus GG: Cloning,Expression, Purification,Crystallization and Preliminary X-Ray Diffraction Study

Crystallography Reports - Sortases are membrane-associated cysteine transpeptidases found mainly in Gram-positive bacteria. They have been intensely studied in pathogenic strains as they play a key...     

Preparation,Crystallization, and Preliminary X-Ray Diffraction Study of Mutant Carboxypeptidase T Bearing the Primary Specificity Pocket and the Active-Site Loop of Carboxypeptidase B

Crystallography Reports - Crystals of mutant carboxypeptidase T from Thermoactinomyces vulgaris (CPT11QG) with amino-acid substitutions G215S, Q249G, A251G, T257A, D260G, T262D, and L254I and with...     

Crystallization and Preliminary X-ray Diffraction Study of a Mutant of L-Asparaginase from Wolinella succinogenes

Crystallography Reports - The double mutant of Wolinella succinogenes L-asparaginase (Was72) with the V23Q and K24T substitutions in the C-terminal region of the N-terminal loop enclosing the...     

Methods of Coherent X-Ray Diffraction Imaging

Crystallography Reports - Methods of coherent X-ray diffraction imaging of the spatial structure of noncrystalline objects and nanocrystals (nanostructures) are considered. Particular attention is...     

X-Ray Diffraction Studies of Liquid Crystalline Polymers

Thermotropic liquid crystalline copolyesters display an ordered fluid phase at elevated temperatures which permits the development of unusually high orientation at ambient temperatures. The transition which occurs upon cooling the high temperature nematic liquid crystalline phase very rapidly (e.g. fiber spinning) results in a polymeric glass with nematic structural order. Annealing increases structural order from the nematic glass toward ideal three dimensional crystalline order. Precision X-ray diffractometry has been used to directly observe changes in structural correlations which occur with annealing. Structural transitions range in character in these copolyesters from no change upon annealing to a transition from fully two dimensional to fully three dimensional structural order. Increased three dimensional order also results in substantially increased first order character of the high temperature phase transition. The chemical structure of co-monomers determines, in part, the final degree of dimensionality.     

Investigation of the Cholesteryl Oleate Mesophases by X-Ray Diffraction

The following phase transitions occurring in the cholesteryl oleate were investigated by X-ray diffraction: solid-isotropic liquid, isotropic liquid-cholesteric, cholesteric-smectic.

The sample purity was 98%. Strong pretransitional effects were observed at the solid-isotropic liquid phase transition and at the cholesteric-smectic phase transition.

At this last transition the longitudinal coherence length ξ_∥ appears to diverge as the critical temperature is approached in the cholesteric phase, whereas the transversal coherence length ξ_τ increases at the critical temperature in the smectic phase in an abrupt way. It seems from the temperature dependence analysis of the angular position of the low angle peak that the smectic phase is a smectic A phase and that a progressive melting of chains occurs at the temperature increases.     

Experimental and Theoretical Study of the Triple-Crystal High-Resolution X-Ray Diffraction Scheme in Reciprocal Space Mapping Technique

Crystallography Reports - The triple-crystal high-resolution X-ray diffraction scheme has been experimentally and theoretically investigated using reciprocal space mapping. The procedure for...     

The Use of X-Ray Diffraction in the Study of Thermotropic Liquid Crystals With Rod-Like Molecules

The paper first reviews briefly the various kinds of information that can be obtained from x-ray diffraction studies. Next, specific examples are given from the literature of determinations of each of the different kinds of data.     

Ray Theories in X-Ray Diffraction and Memories on the Borrmann Effect

The ray theories in ordinary optics are reviewed based on the Poynting vector and the wave packet for electromagnetic waves. They are extended to the two-beam (waves) cases in X-ray diffraction, because the rays are closely related to the Borrmann effect. It is pointed out that the approach of the wave packet is more fundamental than that of the Poynting vector. Some personal reminiscences of the Borrmann effect and of Borrmann himself are described.     

X-Ray Diffraction and Physical Properties of Potassium Fullerides KxC70

Abstract

X-ray diffraction and magnetic-susceptibility measurements have been carried out for single phase K_xC₇₀ (x=1, 3, 4, 6 and 9) compounds synthesized by heating stoichiometric amount of K₉C₇₀ and C₇₀. The x-ray diffraction profiles show no structural transition down to 10K. The fairly large temperature-independent paramagnetic contribution was observed in x=3 and 4. The electrical resistivity has been measured for K evaporated C₇₀ film with increasing K thickness. Two resistivity minima were observed at x=1 and 4.     

Crystallization and X-Ray Diffraction Studies of Salmonella Invasion Protein D (SipD), Insight Tip Component of Salmonella typhi Type III Secretion System

Crystallography Reports - Many pathogenic gram-negative bacteria including Salmonella typhi utilize type III secretion systems (T3SSs) to inject bacterial proteins into host cells and to initiate...     

Erratum to:Methods of Coherent X-Ray Diffraction Imaging

Crystallography Reports - An Erratum to this paper has been published: https://doi.org/10.1134/S106377452134006X     

Raman Scattering and X-Ray Diffraction Studies on Alkali-Metal Intercalated Clays

Abstract

Vermiculite and fluor-tetrasilicic mica were intercalated with alkali metals (Na, K and Rb) by vapor transport. X-ray and Raman scattering experiments were conducted to study the structure and lattice dynamics of the new clay compounds. When Rb and K atoms were intercalated to the host materials, superlattices were formed. In Na intercalated compounds, however, no superlattice x-ray diffraction peaks were found. Raman spectra exhibited drastic changes after alkali-metal intercalation, reflecting the structural changes found by our x-ray diffraction.     

X-Ray Diffraction Study of New Organic Compound n-Tol3Sb[OC(O)CH=CHPh]2

Crystallography Reports - The bis[(2E)-3-phenylprop-2-enoate]-tris(п-tolyl)antimony n-Tol3Sb[OC(O)CH=CHPh]2 complex is obtained as a result of interaction of tri-n-tolylantimony, hydrogen...     

X-Ray Topography of Perfect Crystals using the Laue-Laue Three-Beam Case of Diffraction

A new kind of experiments is possible using very good collimated X-rays with a divergence of the incident beam smaller than the diffraction curve (rocking curve) of perfect crystals. Some examples are shown for the three-beam case of diffraction where both reflections are in Lauegeometry. The modification of the structure factor of a two-beam case reflection in the neighbourhood of a three-beam case causes a modification in the intensity distribution inside the Borrmann fan, which can be seen in section topographs. The energy flow in the three-beam case can be made visible in experiments with a very narrow incident beam with a 30 × 30 μm² cross-section.     

Synthesis and Molecular Structure Investigation by DFT and X-Ray Diffraction of ARNO

Abstract  

We report here the synthesis of (Z)-5-(4-nitrobenzyliden)-3-N(2-ethoxyphenyl)-2-thioxo-thiazolidin-4-one (ARNO) compound. The crystal structure has been determined by X-ray diffraction. The compound crystallizes in the triclinic system with space group P[`1] P\bar{1} and cell parameters: a = 9.1289(19), b = 9.3717(7), c = 12.136(3) ?, α = 102.133(11)°, β = 90.99(2)°, γ = 117.165(9)°, V = 895.4(3) ?³ and Z = 2. The structure has been refined to a final R = 0.05 for 2591 observed reflections. The refined structure was found to be significantly non planar. The molecule exhibits intermolecular hydrogen bond of type C–H⋯O and C–H⋯S. ab initio calculations were also were performed at Hartree–Fock and density functional theory levels. The full HF and DFT geometry optimization was carried out using LANL2DZ, 6-31G* and B3LYP/6-31+G** basis sets. The optimized geometry of the title compound was found to be consistent structure determined by X-ray diffraction. The minimum energy of geometrical structure is obtained by using level HF/LANL2DZ basis sets.     

X-Ray Diffraction Study of the Crystal Structure of 2-[Phenyl-(2-hydroxyethylthio)methyl]-cyclohexanone,a Candidate Prodrug of the Cytotoxin E-2-Benzylidenecyclohexanone

Crystallography Reports - This investigation describes the synthesis and X-ray diffraction study of the crystal structure of a novel prodrug 2-[phenyl-(2-hydroxyethylthio)methyl]cyclohexanone (2)....     

X-Ray Diffraction Interferometer with One Slit: Computer Simulations and Analytics

Crystallography Reports - A theoretical basis and a method of accurate computer simulations for studying the properties of X-ray diffraction interferometer with one slit are formulated. The slit...