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Resulting Crystals (resulting + crystal)

Distribution by Scientific Domains

Chemistry	83%

Selected Abstracts

Partial ordering of tripivaloylmethane at 110,K

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2008
Vladimir Stilinovi
Tripivaloylmethane [systematic name: 4-(2,2-dimethylpropanoyl)-2,2,6,6-tetramethylheptane-3,5-dione], C16H28O3, is known to crystallize at room temperature in the space group R3m with three molecules in the unit cell. The molecules are conformationally chiral and pack so that each molecular site is occupied with equal probability by the two enantiomers. Upon cooling to 110,K, the structure partially orders; two molecules in the unit cell order into two different conformations of opposite chirality, while the third remains disordered. The symmetry of the resulting crystal is P3, with each of the molecules lying about a different threefold rotation axis. This paper describes an unusual case of order,disorder phase transition in which the structure partially orders by changes of molecular conformation in the single crystals. Such behaviour is of interest in the study of phase transitions and molecular motion in the solid state. [source]

A preliminary neutron diffraction study of ,-chymotrypsin

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2009
Walter R. P. Novak
The crystal preparation and preliminary neutron diffraction analysis of ,-chymotrypsin are presented. Large hydrogenated crystals of ,-chymotrypsin were exchanged into deuterated buffer via vapor diffusion in a capillary and neutron Laue diffraction data were collected from the resulting crystal to 2.0,Å resolution on the LADI-III diffractometer at the Institut Laue,Langevin (ILL) at room temperature. The neutron structure of a well studied protein such as ,-chymotrypsin, which is also amenable to ultrahigh-resolution X-ray crystallography, represents the first step in developing a model system for the study of H atoms in protein crystals. [source]

Effect of Pb on the properties of Sr2YRu1-xCuxO6 crystals grown from PbO-PbF2 solutions at high temperatures

CRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2007
S. M. Rao
Abstract Single crystals of Sr2YRu1-xCuxO6 with x=0 and x=0.1 were grown using PbO-PbF2 based solutions at different temperatures in the range 1150,1350°C. The influence of Pb from the solutions and the Cu from the solid solutions of Sr2YRu1-xCuxO6 on the resulting crystals was studied using microstructure and magnetic property measurements. The peaks in the powder X-ray diffraction patterns and Raman spectra do not change in the case of x=0 crystals but shift in the presence of Cu. A diamagnetic transition indicative of superconductivity was observed in the presence of Cu and an antiferromagnetic behavior with x=0. Based on these results it is concluded that Pb may not be incorporated in the crystals and even if it does the influence is not observed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Crystallization and preliminary X-ray characterization of the Skp1,Fbg3 complex

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2010
Taichi Kumanomidou
F-box proteins are the substrate-recognition components of Skp1,Cullin1,F-box protein,Rbx1 (SCF) ubiquitin ligase complexes. Fbs1, an F-box protein, binds specifically to proteins modified with high-mannose oligosaccharides. Fbg3, another F-box protein, has 51% sequence identity to Fbs1. Although the residues that are necessary for binding to oligosaccharides are conserved between Fbs1 and Fbg3, Fbg3 does not bind glycoproteins. Skp1 and Fbg3 were co-expressed in Escherichia coli and their complex was purified to homogeneity and crystallized. Microseeding combined with the sandwiched hanging-drop technique improved the quality of the resulting crystals. The plate-shaped crystals belonged to space group P212121, with unit-cell parameters a = 34.1, b = 76.6, c = 193.9,Å and one molecule per asymmetric unit. [source]

Purification, crystallization and preliminary X-ray analysis of urease from jack bean (Canavalia ensiformis)

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2009
Anuradha Balasubramanian
Plant urease is a seed protein that is common in most legumes. It is also common in many bacteria and fungi and several species of yeast. Urease allows organisms to use exogenous and internally generated urea as a nitrogen source by catalyzing the hydrolysis of urea to ammonia and carbon dioxide. Urease from jack bean meal was purified to electrophoretic homogeneity using a series of steps involving acetone precipitation and size-exclusion and ion-exchange chromatography. The jack bean urease was crystallized and the resulting crystals diffracted to 2.05,Å resolution using synchrotron radiation. The crystals belonged to the hexagonal space group P6322, with unit-cell parameters a = b = 138.57, c = 198.36,Å. [source]

Purification, crystallization and preliminary X-ray analysis of urease from pigeon pea (Cajanus cajan)

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2008
Anuradha Balasubramanian
Urease is a seed protein that is common to most Leguminosae. It also occurs in many bacteria, fungi and several species of yeast. Urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide, thus allowing organisms to use exogenous and internally generated urea as a nitrogen source. Urease from pigeon pea seeds has been purified to electrophoretic homogeneity using a series of steps involving ammonium sulfate fractionation, acid precipitation, ion-exchange and size-exclusion chromatography techniques. The pigeon pea urease was crystallized and the resulting crystals diffracted to 2.5,Å resolution. The crystals belong to the rhombohedral space group R32, with unit-cell parameters a = b = 176.29, c = 346.44,Å. [source]