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Preliminary X-ray Diffraction Data (preliminary + x-ray_diffraction_data)
Selected AbstractsCrystallization and preliminary X-ray diffraction data of an LNA 7-mer duplex derived from a ricin aptamerACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2009Charlotte Förster Locked nucleic acids (LNAs) are modified nucleic acids which contain a modified sugar such as , - d -2,- O,4,- C methylene-bridged ribofuranose or other sugar derivatives in LNA analogues. The ,- d -2,- O,4,- C methylene ribofuranose LNAs in particular possess high stability and melting temperatures, which makes them of interest for stabilizing the structure of different nucleic acids. Aptamers, which are DNAs or RNAs targeted against specific ligands, are candidates for substitution with LNAs in order to increase their stability. A 7-mer helix derived from the terminal part of an aptamer that was targeted against ricin was chosen. The ricin aptamer originally consisted of natural RNA building blocks and showed high affinity in ricin binding. For future stabilization of the aptamer, the terminal helix has been constructed as an `all-locked' LNA and was successfully crystallized in order to investigate its structural properties. Optimization of crystal growth succeeded by the use of different metal salts as additives, such as CuCl2, MgCl2, MnCl2, CaCl2, CoCl2 and ZnSO4. Preliminary X-ray diffraction data were collected and processed to 2.8,Å resolution. The LNA crystallized in space group P65, with unit-cell parameters a = 50.11, b = 50.11, c = 40.72,Å. The crystals contained one LNA helix per asymmetric unit with a Matthews coefficient of 3.17,Å3,Da,1, which implies a solvent content of 70.15%. [source] Expression, purification, crystallization and preliminary X-ray diffraction analysis of dihydrodipicolinate synthase from Bacillus anthracis in the presence of pyruvateACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 2 2009Jarrod E. Voss Dihydrodipicolinate synthase (DHDPS) catalyses the first committed step in the lysine-biosynthesis pathway in bacteria, plants and some fungi. In this study, the expression of DHDPS from Bacillus anthracis (Ba -DHDPS) and the purification of the recombinant enzyme in the absence and presence of the substrate pyruvate are described. It is shown that DHDPS from B. anthracis purified in the presence of pyruvate yields greater amounts of recombinant enzyme with more than 20-fold greater specific activity compared with the enzyme purified in the absence of substrate. It was therefore sought to crystallize Ba -DHDPS in the presence of the substrate. Pyruvate was soaked into crystals of Ba -DHDPS prepared in 0.2,M sodium fluoride, 20%(w/v) PEG 3350 and 0.1,M bis-tris propane pH 8.0. Preliminary X-ray diffraction data of the recombinant enzyme soaked with pyruvate at a resolution of 2.15,Å are presented. The pending crystal structure of the pyruvate-bound form of Ba -DHDPS will provide insight into the function and stability of this essential bacterial enzyme. [source] Expression, purification, crystallization and preliminary X-ray diffraction data of methylmalonate-semialdehyde dehydrogenase from Bacillus subtilisACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2004Hélène Dubourg Methylmalonate-semialdehyde dehydrogenase from Bacillus subtilis was cloned and overexpressed in Escherichia coli. Suitable crystals for X-ray diffraction experiments were obtained by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. The crystals belong to space group P212121, with unit-cell parameters a = 195.2, b = 192.5, c = 83.5,Å, and contain one tetramer per asymmetric unit. X-ray diffraction data were collected to 2.5,Å resolution using a synchrotron-radiation source. The crystal structure was solved by the molecular-replacement method. [source] Mouse testis,brain RNA-binding protein (TB-RBP): expression, purification and crystal X-ray diffractionACTA CRYSTALLOGRAPHICA SECTION D, Issue 11 2001John M. Pascal TB-RBP (testis,brain RNA-binding protein) is a mouse RNA-binding protein that controls the temporal and spatial expression of mRNA. Found most abundantly in brain and male germ cells in the testis, TB-RBP is known to suppress the translation of specific testicular and brain mRNAs as part of cell development. TB-RBP,mRNA complexes can bind microtubules and thereby facilitate RNA translocation. Translin is the human orthologue of TB-RBP which binds to single-stranded ends of DNA sequences in breakpoint regions of chromosomal translocations. TB-RBP/translin has been crystallized in space group P21212. The expression, purification, and crystallization of TB-RBP are described as well as preliminary X-ray diffraction data. The multimeric state of TB-RBP is addressed using dynamic light-scattering results. [source] Crystallization and preliminary X-ray diffraction data of mouse L-chain apoferritin crystalsACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2000Thierry Granier Crystals of recombinant mouse L-chain apoferritin were obtained by the hanging-drop technique using ammonium sulfate as precipitant. Two crystal forms were observed in the same drop. The crystals belong to either the P2 monoclinic or to the P4212 tetragonal space group. The monoclinic crystals diffracted to beyond 2.4,Å resolution but were systematically twinned, while the tetragonal crystals diffracted to beyond 2.9,Å. These crystallization conditions in the absence of metal salts should facilitate the study of the interaction between L-chain ferritins and heavy metals, particularly the iron core. [source] Crystallization and preliminary X-ray diffraction data of ,-galactosidase from Saccharomyces cerevisiaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2010Rafael Fernández-Leiro Saccharomyces cerevisiae,-galactosidase is a highly glycosylated extracellular protein that catalyzes the hydrolysis of ,-galactosidic linkages in various glucids. Its enzymatic activity is of interest in many food-related industries and has biotechnological applications. Glycosylated and in vitro deglycosylated protein samples were both assayed for crystallization, but only the latter gave good-quality crystals that were suitable for X-ray crystallography. The crystals belonged to space group P4212, with unit-cell parameters a = b = 101.24, c = 111.52,Å. A complete diffraction data set was collected to 1.95,Å resolution using a synchrotron source. [source] Crystallization and preliminary X-ray diffraction data of an LNA 7-mer duplex derived from a ricin aptamerACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2009Charlotte Förster Locked nucleic acids (LNAs) are modified nucleic acids which contain a modified sugar such as , - d -2,- O,4,- C methylene-bridged ribofuranose or other sugar derivatives in LNA analogues. The ,- d -2,- O,4,- C methylene ribofuranose LNAs in particular possess high stability and melting temperatures, which makes them of interest for stabilizing the structure of different nucleic acids. Aptamers, which are DNAs or RNAs targeted against specific ligands, are candidates for substitution with LNAs in order to increase their stability. A 7-mer helix derived from the terminal part of an aptamer that was targeted against ricin was chosen. The ricin aptamer originally consisted of natural RNA building blocks and showed high affinity in ricin binding. For future stabilization of the aptamer, the terminal helix has been constructed as an `all-locked' LNA and was successfully crystallized in order to investigate its structural properties. Optimization of crystal growth succeeded by the use of different metal salts as additives, such as CuCl2, MgCl2, MnCl2, CaCl2, CoCl2 and ZnSO4. Preliminary X-ray diffraction data were collected and processed to 2.8,Å resolution. The LNA crystallized in space group P65, with unit-cell parameters a = 50.11, b = 50.11, c = 40.72,Å. The crystals contained one LNA helix per asymmetric unit with a Matthews coefficient of 3.17,Å3,Da,1, which implies a solvent content of 70.15%. [source] Crystallization and preliminary X-ray diffraction analysis of mouse galectin-4 N-terminal carbohydrate recognition domain in complex with lactoseACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2008Veronika Krej, íková Galectin-4 is thought to play a role in the process of tumour conversion of cells of the alimentary tract and the breast tissue; however, its exact function remains unknown. With the aim of elucidating the structural basis of mouse galectin-4 (mGal-4) binding specificity, we have undertaken X-ray analysis of the N-terminal domain, CRD1, of mGal-4 in complex with lactose (the basic building block of known galectin-4 carbohydrate ligands). Crystals of CRD1 in complex with lactose were obtained using vapour-diffusion techniques. The crystals belong to tetragonal space group P4212 with unit-cell parameters a = 91.1, b = 91.16, c = 57.10,Å and preliminary X-ray diffraction data were collected to 3.2,Å resolution. An optimized crystallization procedure and cryocooling protocol allowed us to extend resolution to 2.1,Å. Structure refinement is currently under way; the initial electron-density maps clearly show non-protein electron density in the vicinity of the carbohydrate binding site, indicating the presence of one lactose molecule. The structure will help to improve understanding of the binding specificity and function of the potential colon cancer marker galectin-4. [source] | ||||||||||