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Good-quality Crystals (good-quality + crystal)
Selected AbstractsPurification, crystallization and preliminary X-ray diffraction studies of parakeet (Psittacula krameri) haemoglobinACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 10 2009S. M. Jaimohan Birds often show efficient oxygen management in order to meet the special demands of their metabolism. However, the structural studies of avian haemoglobins (Hbs) are inadequate for complete understanding of the mechanism involved. Towards this end, purification, crystallization and preliminary X-ray diffraction studies have been carried out for parakeet Hb. Parakeet Hb was crystallized as the met form in low-salt buffered conditions after extracting haemoglobin from crude blood by microcentrifugation and purifying the sample by column chromatography. Good-quality crystals were grown from 10% PEG 3350 and a crystal diffracted to about 2.8,Å resolution. Preliminary diffraction data showed that the Hb crystal belonged to the monoclinic system (space group C2), with unit-cell parameters a = 110.68, b = 64.27, c = 56.40,Å, , = 109.35°. Matthews volume analysis indicated that the crystals contained a half-tetramer in the asymmetric unit. [source] Harvesting the high-hanging fruit: the structure of the YdeN gene product from Bacillus subtilis at 1.8,Å resolutionACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2004Izabela Janda High-throughput (HT) protein crystallography is severely impeded by the relatively low success rate of protein crystallization. Proteins whose structures are not solved in the HT pipeline owing to attrition in any phase of the project are referred to as the high-hanging fruit, in contrast to those proteins that yielded good-quality crystals and crystal structures, which are referred to as low-hanging fruit. It has previously been shown that proteins that do not crystallize in the wild-type form can have their surfaces engineered by site-directed mutagenesis in order to create patches of low conformational entropy that are conducive to forming intermolecular interactions. The application of this method to selected proteins from the Bacillus subtilis genome which failed to crystallize in the HT mode is now reported. In this paper, the crystal structure of the product of the YdeN gene is reported. Of three prepared double mutants, i.e. E124A/K127A, E167A/E169A and K88A/Q89A, the latter gave high-quality crystals and the crystal structure was solved by SAD at 1.8,Å resolution. The protein is a canonical ,/, hydrolase, with an active site that is accessible to solvent. [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 studies of the N-domain of the Wilson disease associated proteinACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2009Lili Liu Wilson disease associated protein (ATP7B) is essential for copper transport in human cells. Mutations that affect ATP7B function result in Wilson's disease, a chronic copper toxicosis. Disease-causing mutations within the N-domain of ATP7B (WND) are known to disrupt ATP binding, but a high-resolution X-ray structure of the ATP-binding site has not been reported. The N-domain was modified to delete the disordered loop comprising residues His1115,Asp1138 (WND,1115,1138). Unlike the wild-type N-domain, WND,1115,1138 formed good-quality crystals. Synchrotron diffraction data have been collected from WND,1115,1138 at the Canadian Light Source. A native WND,1115,1138 crystal diffracted to 1.7,Å resolution and belonged to space group P42212, with unit-cell parameters a = 39.2, b = 39.2, c = 168.9,Å. MAD data were collected to 2.7,Å resolution from a SeMet-derivative crystal with unit-cell parameters a = 38.4, b = 38.4, c = 166.7,Å. The WND,1115,1138 structure is likely to be solved by phasing from multiwavelength anomalous diffraction (MAD) experiments. [source] | ||||||||||