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Preliminary Crystallographic Study (preliminary + crystallographic_study)
Selected AbstractsPreliminary crystallographic study of Thermus aquaticus glycerol kinaseACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2001Hua-Shan Huang Glycerol kinase (GlpK) is an important enzyme which catalyzes the rate-limiting step in a central biochemical pathway involving glycerol metabolism. GlpK from the thermophile Thermus aquaticus has been overexpressed in glpK -deficient Escherichia coli and crystallized by the hanging-drop method. The crystal belongs to the cubic space group I23, with unit-cell parameters a = b = c = 163.94,(3),Å. Native data were collected to 2.87,Å resolution on a Cu,K, rotating-anode X-ray source. [source] Preliminary crystallographic study of the Streptococcus agalactiae sortases, sortase A and sortase C1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2010Baldeep Khare Sortases are cysteine transpeptidases that are essential for the assembly and anchoring of cell-surface adhesins in Gram-positive bacteria. In Streptococcus agalactiae (GBS), the pilin-specific sortase SrtC1 catalyzes the polymerization of pilins encoded by pilus island 1 (PI-1) and the housekeeping sortase SrtA is necessary for cell-wall anchoring of the resulting pilus polymers. These sortases are known to utilize different substrates for pilus polymerization and cell-wall anchoring; however, the structural correlates that dictate their substrate specificity have not yet been clearly defined. This report presents the expression, purification and crystallization of SrtC1 (SAG0647) and SrtA (SAG0961) from S. agalactiae strain 2603V/R. The GBS SrtC1 has been crystallized in three crystal forms and the GBS SrtA has been crystallized in one crystal form. [source] Preliminary crystallographic study of two cuticle-degrading proteases from the nematophagous fungi Lecanicillium psalliotae and Paecilomyces lilacinusACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2009Fengping Ye Cuticle-degrading proteases are extracellular subtilisin-like serine proteases that are secreted by entomopathogenic and nematophagous fungi. These proteases can digest the host cuticle during invasion of an insect or nematode and serve as a group of important virulence factors during the infection of nematodes by nematophagous fungi. To elucidate the mechanism of interaction between the proteases and the nematode cuticle, two cuticle-degrading proteases, Ver112 from Lecanicillium psalliotae (syn. Verticillium psalliotae) and PL646 from Paecilomyces lilacinus, were studied. The Ver112 protein and the complex between PL646 and the substrate-like tetrapeptide inhibitor methoxysuccinyl-Ala-Ala-Pro-Val-chloromethyl ketone (MSU-AAPV) were crystallized using the hanging-drop vapour-diffusion method at 289,K. The crystals were analyzed by X-ray diffraction to resolutions of 1.65 and 2.2,Å, respectively. These analyses identified that crystals of Ver112 belonged to space group P212121, with unit-cell parameters a = 43.7, b = 67.8, c = 76.3,Å, , = , = , = 90°. In contrast, crystals of the PL646,MSU-AAPV complex belonged to space group P21, with unit-cell parameters a = 65.1, b = 62.5, c = 67.6,Å, , = 92.8°. [source] Expression, refolding, crystallization and preliminary crystallographic study of MHC H-2Kk complexed with octapeptides and nonapeptidesACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2004Christine Kellenberger Major histocompatibility complex (MHC) molecules are heterodimeric cell-surface receptors that play a crucial role in the cellular immune response by presenting epitope peptides to T-cell antigen receptors (TCR). Although the structural basis of the peptide,MHC binding mechanism is becoming better understood, it is still difficult to predict a binding mode for an MHC of unknown structure. Therefore, as the first stage of a TCR,MHC interaction study, the crystal structures of the mouse H-2Kk molecule in complex with both an octapeptide from Influenza A virus and a nonapeptide from simian virus SV40 were solved. Here, the expression, refolding, purification and crystallization of the two complexes are reported. For the H-2Kk,HA(259,266) complex, crystals were obtained via an extensive screen using a nanodrop-dispensing robot and diffracted to 2.5,Å resolution. For the H-2Kk,SV40(560,568) complex, microscopic needles were initially obtained and their size was improved by macroseeding and a stepwise increase in precipitant concentration. Diffraction data to a resolution of 3.0,Å were collected at a synchrotron facility. [source] Crystallization and preliminary crystallographic study of the functional form of the Bacillus thuringiensis mosquito-larvicidal Cry4Aa mutant toxinACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2004Panadda Boonserm The 65,kDa functional form of the mosquito-larvicidal Cry4Aa-R235Q mutant toxin has been crystallized. The crystals belong to space group C2221, with unit-cell parameters a = 91.2, b = 202.1, c = 98.7,Å, and contain one molecule per asymmetric unit. The crystals diffract to ,2.9,Å using synchrotron radiation and a complete native data set has been collected. The structure has been solved using a molecular-replacement method with the Cry4Ba toxin protein as a search model. [source] Structural genomics of the SARS coronavirus: cloning, expression, crystallization and preliminary crystallographic study of the Nsp9 proteinACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2003Valérie Campanacci The aetiologic agent of the recent epidemics of Severe Acute Respiratory Syndrome (SARS) is a positive-stranded RNA virus (SARS-CoV) belonging to the Coronaviridae family and its genome differs substantially from those of other known coronaviruses. SARS-CoV is transmissible mainly by the respiratory route and to date there is no vaccine and no prophylactic or therapeutic treatments against this agent. A SARS-CoV whole-genome approach has been developed aimed at determining the crystal structure of all of its proteins or domains. These studies are expected to greatly facilitate drug design. The genomes of coronaviruses are between 27 and 31.5,kbp in length, the largest of the known RNA viruses, and encode 20,30 mature proteins. The functions of many of these polypeptides, including the Nsp9,Nsp10 replicase-cleavage products, are still unknown. Here, the cloning, Escherichia coli expression, purification and crystallization of the SARS-CoV Nsp9 protein, the first SARS-CoV protein to be crystallized, are reported. Nsp9 crystals diffract to 2.8,Å resolution and belong to space group P61/522, with unit-cell parameters a = b = 89.7, c = 136.7,Å. With two molecules in the asymmetric unit, the solvent content is 60% (VM = 3.1,Å3,Da,1). [source] Crystallization and preliminary X-ray diffraction analysis of a rat biliverdin reductaseACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2000Danyu Sun Biliverdin reductase (BVR) catalyzes the final step of haem degradation and converts biliverdin to bilirubin using NAD(P)H as an electron donor. This paper deals with the first crystallization and preliminary crystallographic study of recombinant rat BVR expressed in Escherichia coli. Crystals of BVR were obtained by the sitting-drop vapour-diffusion method. Using synchrotron radiation at station BL44B2 of SPring-8, Japan, BVR diffraction data were collected to 1.6,Å resolution. Crystals belong to the orthorhombic space group P212121, with unit-cell parameters a = 58.89, b = 70.41, c = 87.76,Å. The complete determination of the crystallographic structure is currently in progress using MAD (multiwavelength anomalous diffraction) data from an Ir-derivative crystal. [source] Crystallization and preliminary crystallographic study of triple-helical DNAACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2000Zong-Jin Han Single crystals of d(CTCCTSCCGCGCG)·d(CGCGCGGAG) have been grown by the vapor-diffusion method using 2-methyl-2,4-pentanediol as a precipitant. The crystals are tetragonal, space group P42, with unit-cell parameters a = b = 53.8, c = 43.1,Å, and diffract to 1.8,Å resolution at a synchrotron X-ray beamline. In the crystal, the asymmetric unit contains one copy of the construct. The two halves of the structure are related by non-crystallographic twofold symmetry. These observations are consistent with the conclusion that the sequences of the 12-mer and 9-mer oligonucleotides form a duplex DNA at one end and a triplex DNA at the other end. [source] Expression, crystallization and preliminary crystallographic study of mouse hepatitis virus (MHV) nucleocapsid protein C-terminal domainACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2010Xiaohang Tong Mouse hepatitis virus (MHV) belongs to the group II coronaviruses. The virus produces nine genes encoding 11 proteins that could be recognized as structural proteins and nonstructural proteins and are crucial for viral RNA synthesis. The nucleocapsid (N) protein, one of the structural proteins, interacts with the 30.4,kb virus genomic RNA to form the helical nucleocapsid and associates with the membrane glycoprotein via its C-terminus to stabilize virion assembly. Here, the expression and crystallization of the MHV nucleocapsid protein C-terminal domain are reported. The crystals diffracted to 2.20,Å resolution and belonged to space group P422, with unit-cell parameters a = 66.6, c = 50.8,Å. Assuming the presence of two molecules in the asymmetric unit, the solvent content is 43.0% (VM = 2.16,Å3,Da,1). [source] A preliminary crystallographic study of recombinant NicX, an Fe2+ -dependent 2,5-dihydroxypyridine dioxygenase from Pseudomonas putida KT2440ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2010José Ignacio Jiménez NicX from Pseudomonas putida KT2440 is an Fe2+ -dependent dioxygenase that is involved in the aerobic degradation of nicotinic acid. The enzyme converts 2,5-dihydroxypyridine to N -formylmaleamic acid when overexpressed in Escherichia coli. Biophysical characterization of NicX by analytical gel-filtration chromatography revealed that it behaves as an oligomeric assembly in solution, with an apparent molecular weight that is consistent with a hexameric species. NicX was crystallized by the hanging-drop vapour-diffusion method at 291,K. Diffraction data were collected to a resolution of 2.0,Å at the ESRF. The crystals most probably belong to the orthorhombic space group C222 or C2221. The estimated Matthews coefficient was 2.4,Å3,Da,1, corresponding to 50% solvent content, which is consistent with the presence of three protein molecules in the asymmetric unit. Analysis of the crystal data together with chromatographic results supports NicX being a hexameric assembly composed of two cyclic trimers. Currently, crystallization of recombinant selenomethionine-containing NicX is in progress. [source] Purification, crystallization and preliminary crystallographic study of haemoglobin from camel (Camelus dromedarius): a high oxygen-affinity lowland speciesACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2009M. Balasubramanian Haemoglobin is a prototypical allosteric protein that is mainly involved in the transportation of oxygen from the lungs to tissues and of carbon dioxide back to the lungs in an intrinsically coordinated manner to maintain the viability of cells. Haemoglobin from Camelus dromedarius provides an interesting case study of adaptation to life in deserts at extremely high temperatures. An ambition to unravel the integrated structural and functional aspects of the casual survival of this animal at high temperatures led us to specifically work on this problem. The present work reports the preliminary crystallographic study of camel haemoglobin. Camel blood was collected and the haemoglobin was purified by anion-exchange chromatography and crystallized using the hanging-drop vapour-diffusion method under buffered high salt concentration using PEG 3350 as a precipitant. Intensity data were collected using a MAR 345 dtb image-plate detector system. Camel haemoglobin crystallized in the monoclinic space group P21, with one whole biological molecule (,2,2) in the asymmetric unit and unit-cell parameters a = 52.759, b = 116.782, c = 52.807,Å, , = 120.07°. [source] Expression, crystallization and preliminary crystallographic study of human coronavirus HKU1 nonstructural protein 9ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2009Wei Wang Human coronavirus HKU1 (HCoV-HKU1) belongs to coronavirus group II and encodes 16 nonstructural proteins (nsps) which mediate genome replication and transcription. Among these nsps, nsp9 has been shown to possess single-stranded DNA/RNA-binding properties. The gene that encodes HCoV-HKU1 nsp9 was cloned and expressed in Escherichia coli and the protein was subjected to crystallization trials. The crystals diffracted to 2.7,Å resolution and belonged to space group P21212, with unit-cell parameters a = 83.5, b = 88.4, c = 31.2,Å, , = , = , = 90° and two molecules per asymmetric unit. [source] Expression, purification, crystallization and preliminary crystallographic study of the carboxyl-terminal domain of the human voltage-gated proton channel Hv1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2009Shu Jie Li The voltage-gated proton channel Hv1 is essential to proton permeation and contains a voltage-sensor domain without a pore domain. It contains three predicted domains: an N-terminal acid and proline-rich domain, a transmembrane voltage-sensor domain and a C-terminal domain that is responsible for the dimeric architecture of Hv1. Here, the C-terminal domain of the human voltage-gated proton channel Hv1 (C-Hv1) was overexpressed in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method. The crystals have a tetragonal form and diffraction data were collected to 2.5,Å resolution in-house. The crystal belongs to space group P41212, with unit-cell parameters a = b = 37.76, c = 137.52,Å. Structural determination of C-Hv1 is in progress. [source] Purification, crystallization and preliminary crystallographic study of low oxygen-affinity haemoglobin from cat (Felis silvestris catus) in two different crystal formsACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2009M. Balasubramanian Haemoglobin is a metalloprotein which plays a major role in the transportation of oxygen from the lungs to tissues and of carbon dioxide back to the lungs. The present work reports the preliminary crystallographic study of low oxygen-affinity haemoglobin from cat in different crystal forms. Cat blood was collected, purified by anion-exchange chromatography and crystallized in two different conditions by the hanging-drop vapour-diffusion method under unbuffered low-salt and buffered high-salt concentrations using PEG 3350 as a precipitant. Intensity data were collected using MAR345 and MAR345dtb image-plate detector systems. Cat haemoglobin crystallizes in monoclinic and orthorhombic crystal forms with one and two whole biological molecules (,2,2), respectively, in the asymmetric unit. [source] Overexpression, purification, characterization and preliminary crystallographic study of phosphoglycolate phosphatase from Shigella flexneri 2a strain 301ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2009Heli Liu Phosphoglycolate phosphatase has a salvage function in the metabolism of the 2-phosphoglycolate formed during bacterial DNA repair. In order to better understand its dimerization behaviour, the influence of metal ions on its activity and its catalytic mechanism at the molecular level, recombinant phosphoglycolate phosphatase from Shigella flexneri was overexpressed, purified, characterized and crystallized by the hanging-drop vapour-diffusion method at 291,K using polyethylene glycol 3500 as a precipitant and zinc acetate as an additive. The crystals belonged to space group R3, with unit-cell parameters a = 88.1, b = 88.1, c = 259.2,Å, corresponding to the presence of two molecules in the asymmetric unit. SeMet-labelled protein was also prepared and crystallized for use in phase determination. Initial structure determination using the multiwavelength anomalous dispersion (MAD) method clearly revealed that SfPGPase bears an ,-helical cap domain that differs from that of a previously reported orthologue. [source] Cloning, expression, purification, crystallization and preliminary crystallographic study of the protein module (BIV2-Helix) in the fusion core of bovine immunodeficiency-like virus (BIV) gp40ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 2 2005Xiaodong Zhao The fusion core of bovine immunodeficiency virus (BIV) gp40 is proposed to be involved in membrane fusion. However, no crystal structures are yet available. A predicted protein module BIV2-Helix of BIVgp40 has been expressed in Escherichia coli and purified by chromatography. Recombinant BIV2-Helix was crystallized using the hanging-drop vapour-diffusion technique at 291,K. The crystals were grown in MPD and belonged to the primitive rhombohedral space group R3, with unit-cell parameters a = 39.17, b = 39.17, c = 295.05,Å and two molecules per asymmetric unit. X-ray diffraction data were collected to 1.76,Å in the home laboratory from a single crystal. [source] | ||||||||||