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Monoclinic Space Group P21 (monoclinic + space_group_p21)
Kinds of Monoclinic Space Group P21 Selected AbstractsSynthesis and crystal structure investigation of pyridine-2-(3,-mercaptopropanoic acid)- N -oxideCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2007R. Ramasubramanian Abstract Pyridine-2-(3,-mercaptopropanoic acid)- N -oxide (I), is a higher homologue of 1-oxopyridinium-2-thioacetic acid (II) [1]. It crystallizes in monoclinic space group P21 with a = 9.2168(2) Å, b = 4.1423(2) Å, c = 11.3904(4) Å, , = 98.65(2)°, V = 429.93(3) Å3 and Z = 2. The least-squares refinement gave residual index R = 0.024 for 1070 observed reflections. The introduction of an additional methylene group in (II) causes a flip in the carboxylic acid group of (I) that facilitates the molecules to align infinite antiparallel chains through strong C,H···O interactions. The molecules are interlinked by O,H···O hydrogen bonding across the chains and forming an infinite screw chain along y-direction. The molecular packing is stabilized by O,H···O and C,H···O hydrogen bonding and ,-, electron interactions. This is an important facet of the crystal packing. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] New Organic Nonlinear Optical Polyene Crystals and Their Unusual Phase Transitions,ADVANCED FUNCTIONAL MATERIALS, Issue 11 2007O-P. Kwon Abstract A series of new nonlinear optical chromophores based on configurationally locked polyenes (CLPs) with chiral pyrrolidine donors are synthesized. All CLP derivatives exhibit high thermal stability with decomposition temperatures Td at least > ,270,°C. Acentric single crystals of enantiopure D - and L -prolinol-based chromophores with a monoclinic space group P21 exhibit a macroscopic second-order nonlinearity that is twice as large than that of analogous dimethylamino-based crystal. This is attributed to a strong hydrogen-bonded polar polymer-like chain built by these molecules, which is aligned along the polar crystallographic b -axis. Five ,-phase CLP crystals with different donors grown from solution exhibit a reversible or irreversible thermally induced structural phase transition to a ,-phase. These phase transitions are unusual, changing the crystal symmetry from higher to lower at increasing temperatures, for example, from centrosymmetric to non-centrosymmetric, enhancing their macroscopic second-order nonlinear optical properties. [source] N -(2-Carboxybenzoyl)- l -leucine methyl esterACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2006Alvaro B. Onofrio The title compound (with the systematic name 2-{[(1S)-1-(methoxycarbonyl)-3-methylbutyl]aminocarbonyl}benzoic acid), C15H19NO5, crystallizes in the monoclinic space group P21, with two independent molecules per asymmetric unit. The most notable difference between the two molecules is in the dihedral angles between the planes of the carboxyl group and the benzene ring, which are 3.5,(3) and 25.7,(1)°. This difference may account for the fact that two competing reactions are observed in aqueous solution, namely cyclization to form the imide N -phthaloylleucine and hydrolysis of N -(2-carboxybenzoyl)- l -leucine methyl ester to phthalic acid and leucine. [source] Expression, crystallization and preliminary X-ray crystallographic studies of Klebsiella pneumoniae maltohexaose-producing ,-amylaseACTA CRYSTALLOGRAPHICA SECTION D, Issue 12-2 2004Mitsuru Momma A recombinant form of Klebsiella pneumoniae maltohexaose-producing ,-amylase has been overexpressed in Escherichia coli and purified to homogeneity. Crystals were obtained at 293,K by the microbatch technique using 80,mM sodium/potassium phosphate buffer pH 6.2 containing 8% polyethylene glycol 3000, 4% polyethylene glycol 3350 and 40,mM sodium thiocyanate. Crystals of the overexpressed recombinant enzyme diffracted to better than 2.5,Å resolution at 95,K using a synchrotron-radiation source. The crystals belong to the primitive monoclinic space group P21, with unit-cell parameters a = 74.8, b = 107.6, c = 82.2,Å, , = 96.2°. Assuming the presence of two molecules per asymmetric unit, the VM value for the crystal was 2.3,Å3,Da,1, indicating a solvent content of 47%. [source] Crystallization and preliminary X-ray crystallographic analysis of the laminarinase endo-,-1,3-glucanase from Pyrococcus furiosusACTA CRYSTALLOGRAPHICA SECTION D, Issue 12-2 2004Andrea Ilari Laminarinase endo-,-1,3 glucanase (LamA) from Pyrococcus furiosus is an enzyme which displays its main hydrolytic activity on the ,-1,3-glucose polymer laminarin. This laminarinase is remarkably resistant to denaturation: its secondary structure is unchanged in 8,M guanidinium chloride. This protein belongs to the family 16 glycosyl hydrolases, which are enzymes that are widely distributed among bacteria, fungi and higher plants. Single crystals of P. furiosus LamA have been obtained by the hanging-drop vapour-diffusion method using 2-methyl-2,4-pentanediol as a precipitant agent. A complete data set has been collected under cryocooling at a synchrotron source. The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 44.36, b = 84.76, c = 69.23,Å, , = 90, , = 104.97, , = 90°, and diffract to 2.15,Å resolution. [source] Crystallization and preliminary X-ray crystallographic studies of mouse autocrine motility factorACTA CRYSTALLOGRAPHICA SECTION D, Issue 11 2004Noriko Naba Mouse autocrine motility factor (mAMF), a tumour-secreted cytokine that stimulates cell migration in vitro and metastasis in vivo, has been crystallized by the hanging-drop vapour-diffusion method. The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 69.97, b = 115.88, c = 73.27,Å, , = 101.76°. There are two subunits (one dimer) per asymmetric unit. Complexes with four-, five- and six-carbon carbohydrate phosphate inhibitors have also been crystallized. The crystals diffract to at least 1.8,Å resolution and are suitable for X-ray structure analyses at high resolution. [source] Crystallization and preliminary X-ray crystallographic analyses of CMY-1 and CMY-10, plasmidic class C ,-lactamases with extended substrate spectrumACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2004Sun-Joo Lee Plasmid-encoded class C ,-lactamases, including CMY-1 and CMY-10, hydrolyze the lactam bonds of ,-lactam antibiotics, inducing therapeutic failure and a lack of eradication of clinical isolates by third-generation cephalosporins or cephamycins. Therefore, the enzymes are potential targets for developing agents against pathogens isolated from patients suffering from wound infection, urinary tract infection or pneumonia. CMY-1 and CMY-10 were purified and crystallized at 298,K. X-ray diffraction data from CMY-1 and CMY-10 crystals have been collected to 2.5 and 1.5,Å resolution, respectively, using synchrotron radiation. The crystals of the two proteins are isomorphous and belong to the primitive monoclinic space group P21. [source] Crystallization and preliminary X-ray diffraction studies of the water-soluble state of the pore-forming toxin sticholysin II from the sea anemone Stichodactyla helianthusACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2002José M. Mancheño Sticholysin II (StnII) is a potent cytolytic protein produced by the sea anemone Stichodactyla helianthus. StnII belongs to the actinoporin family, a group of proteins which are characterized by their ability to spontaneously interact with biological membranes. The cytolytic character of these proteins is currently explained in terms of a molecular mechanism involving the formation of transmembrane pores. StnII has been crystallized using the hanging-drop vapour-diffusion method at 291,K. Diffraction-quality crystals have unit-cell parameters a = 32.30, b = 119.73, c = 43.42,Å, , = 90.04° and belong to the monoclinic space group P21. Diffraction data to a resolution of 1.71,Å were collected at synchrotron facilities. [source] Crystallization and preliminary X-ray data of the recombinant peptide amidase from Stenotrophomonas maltophiliaACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2002Sebastian Neumann The peptide amidase from Stenotrophomonas maltophilia selectively hydrolyses the C-terminal amide bond in peptide amides. Crystals have been obtained by sitting-drop vapour diffusion from solution containing polyethylene glycol (PEG) 6000, HEPES pH 7.5, glycerine and sodium azide (NaN3). The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 74.18, b = 62.60, c = 101.91,Å, , = 90°. X-ray data from these crystals diffracted at the European Synchrotron Radiation Facility (ESRF, France) ID14-1 beamline to 1.4,Å. [source] Crystallization and preliminary X-ray crystallographic studies of a mutant of ribosome recycling factor from Escherichia coli, Arg132GlyACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2002Hiroaki Nakano Ribosome recycling factor (RRF) plays a central role during the recycling of ribosomes in the final step of protein biosynthesis in prokaryotes and is therefore a favourable target for the development of new antibiotics. The crystal structure of Escherichia coli RRF has been reported to have an open L-shaped conformation, while other RRFs from thermophilic bacteria have a strict L-shaped conformation [Yun et al. (2000), Acta Cryst. D56, 84,85]. Wild-type E. coli RRF has so far not been crystallized free from bound detergent. Here, a mutant of RRF, Arg132Gly, has been crystallized without any detergent. A complete data set from a crystal of this mutant obtained by the hanging-drop vapour-diffusion method has been collected at 2.2,Å resolution using synchrotron radiation at 100,K. The crystal belongs to the monoclinic space group P21, with unit-cell parameters a = 46.02, b = 49.27, c = 49.37,Å, , = 110.1°. The currently refined structure indicates that RRF has a tRNA-like L-shaped conformation. [source] Crystallization and preliminary X-ray analysis of clade I catalases from Pseudomonas syringae and Listeria seeligeriACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2001Xavier Carpena Haem-containing catalases are homotetrameric molecules that degrade hydrogen peroxide. Phylogenetically, the haem-containing catalases can be grouped into three main lines or clades. The crystal structures of seven catalases have been determined, all from clades II and III. In order to obtain a structure of an enzyme from clade I, which includes all plant, algae and some bacterial enzymes, two bacterial catalases, CatF from Pseudomonas syringae and Kat from Listeria seeligeri, have been crystallized by the hanging-drop vapour-diffusion technique, using PEG and ammonium sulfate as precipitants, respectively. Crystals of P. syringae CatF, with a plate-like morphology, belong to the monoclinic space group P21, with unit-cell parameters a = 60.6, b = 153.9, c = 109.2,Å, , = 102.8°. From these crystals a diffraction data set to 1.8,Å resolution with 98% completeness was collected using synchrotron radiation. Crystals of L. seeligeri Kat, with a well developed bipyramidal morphology, belong to space group I222 (or I212121), with unit-cell parameters a = 74.4, b = 121.3, c = 368.5,Å. These crystals diffracted beyond 2.2,Å resolution when using synchrotron radiation, but presented anisotropic diffraction, with the weakest direction perpendicular to the long c axis. [source] Crystallization and preliminary X-ray crystallographic studies on the bacteriophage ,6 RNA-dependent RNA polymeraseACTA CRYSTALLOGRAPHICA SECTION D, Issue 11 2000Sarah J. Butcher The RNA-dependent RNA polymerase (P2) from bacteriophage ,6 has been cloned and the protein overexpressed in Escherichia coli to produce an active enzyme. A fully substituted selenomethionyl version of the protein has also been produced. Crystals of both proteins have been grown; most belong to the monoclinic space group P21, with unit-cell parameters a = 105.9, b = 94.0, c = 140.9,Å, , = 101.4°, but some are trigonal (space group P31 or P32), with unit-cell parameters a = b = 110.1, c = 159.4,Å, , = 120°. Both crystal forms occur in the same crystallization drop and are morphologically indistinguishable. Native data sets have been collected from both types of crystals to better than 3,Å resolution. [source] Purification, crystallization and X-ray analysis of crystals of pectate lyase A from Erwinia chrysanthemiACTA CRYSTALLOGRAPHICA SECTION D, Issue 3 2000Chuong N. Doan Pectate lyase A is secreted by Erwinia chrysanthemi and is a virulence factor for soft rot diseases in plants. Crystals of pectate lyase A were obtained by vapor-diffusion techniques in the presence of polyethylene glycol. The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 48.96, b = 148.86, c = 78.61,Å, , = 97.32°. The crystals contain two protein molecules of 38,kDa per asymmetric unit and diffract to 2.4,Å using Cu,K, radiation. [source] Crystallization and preliminary diffraction studies of a truncated form of a novel protease from spores of Bacillus megateriumACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2000Karthe Ponnuraj During germination of spores of Bacillus species, a novel protease termed GPR initiates the degradation of a group of small acid-soluble spore proteins which protect the dormant spore's DNA from damage. Trypsin digestion of the zymogen of B. megaterium GPR removes ,15 kDa from the C-terminal end of the 46,kDa zymogen subunit, leaving a 30,kDa subunit. Single crystals of this truncated form of GPR have been obtained by the vapor-diffusion method using PEG 4000 as a precipitating agent. The crystals belong to the monoclinic space group P21, with unit-cell parameters a = 67.99, b = 105.34, c = 108.63,Å, , = 95.68°. The cryofrozen crystals diffract X-rays to about 3.3,Å using synchrotron radiation. [source] Crystallization and preliminary X-ray crystallographic study of GenX, a lysyl-tRNA synthetase paralogue from Escherichia coli, in complex with translation elongation factor PACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2010Tomomi Sumida GenX, a lysyl-tRNA synthetase paralogue from Escherichia coli, was overexpressed in E. coli, purified by three chromatographic steps and cocrystallized with a lysyl adenylate analogue (LysAMS) by the hanging-drop vapour-diffusion method using PEG 4000 as a precipitant. The GenX,LysAMS crystals belonged to the triclinic space group P1, with unit-cell parameters a = 54.80, b = 69.15, c = 94.08,Å, , = 95.47, , = 106.51, , = 90.46°, and diffracted to 1.9,Å resolution. Furthermore, GenX was cocrystallized with translation elongation factor P (EF-P), which is believed to be a putative substrate of GenX, and LysAMS using PEG 4000 and ammonium sulfate as precipitants. The GenX,EF-P,LysAMS crystals belonged to the monoclinic space group P21, with unit-cell parameters a = 105.93, b = 102.96, c = 119.94,Å, , = 99.4°, and diffracted to 2.5,Å resolution. Structure determination of the E. coli GenX,LysAMS and GenX,EF-P,LysAMS complexes by molecular replacement was successful and structure refinements are now in progress. [source] Crystallization of BMP receptor type IA bound to the antibody Fab fragment AbD1556ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2010Stefan Harth An antibody Fab fragment, AbD1556, was selected against the extracellular domain of BMP receptor type IA, which blocks the binding of BMP-2 to BMPR-IA and thereby neutralizes BMP-2 activity. To study the mechanism by which BMPR-IA is recognized and bound by the Fab fragment, the complex of AbD1556 bound to BMPR-IA was prepared and crystallized. Crystals of this binary complex belonged to the monoclinic space group P21, with unit-cell parameters a = 89.32, b = 129.25, c = 100.24,Å, , = 92.27°. [source] Preliminary X-ray crystallographic analysis of the d -xylulose 5-phosphate phosphoketolase from Lactococcus lactisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2010Georgiana Petrareanu Phosphoketolases are thiamine diphosphate-dependent enzymes which play a central role in the pentose-phosphate pathway of heterofermentative lactic acid bacteria. They belong to the family of aldehyde-lyases and in the presence of phosphate ion cleave the carbon,carbon bond of the specific substrate d -xylulose 5-phosphate (or d -fructose 6-phosphate) to give acetyl phosphate and d -glyceraldehyde 3-phosphate (or d -erythrose 4-phosphate). Structural information about phosphoketolases is particularly important in order to fully understand their mechanism as well as the steric course of phosphoketolase-catalyzed reactions. Here, the purification, preliminary crystallization and crystallographic characterization of d -xylulose 5-phosphate phosphoketolase from Lactococcus lactis are reported. The presence of thiamine diphosphate during purification was essential for the enzymatic activity of the purified protein. The crystals belonged to the monoclinic space group P21. Diffraction data were obtained to a resolution of 2.2,Å. [source] Crystallization and preliminary crystallographic analysis of Gre2p, an NADP+ -dependent alcohol dehydrogenase from Saccharomyces cerevisiaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2010Klaus Breicha Gre2p [Genes de respuesta a estres (stress-response gene)] from Saccharomyces cerevisiae is a monomeric enzyme of 342 amino acids with a molecular weight of 38.1,kDa. The enzyme catalyses both the stereospecific reduction of keto compounds and the oxidation of various hydroxy compounds and alcohols by the simultaneous consumption of the cofactor NADPH and formation of NADP+. Crystals of a Gre2p complex with NADP+ were grown using PEG 8000 as a precipitant. They belong to the monoclinic space group P21. The current diffraction resolution is 3.2,Å. In spite of the monomeric nature of Gre2p in solution, packing and self-rotation calculations revealed the existence of two Gre2p protomers per asymmetric unit related by a twofold noncrystallographic axis. [source] Crystallization and preliminary X-ray crystallographic analysis of l -rhamnose isomerase with a novel high thermostability from Bacillus haloduransACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2010Thi-Ngoc-Thanh Doan l -Rhamnose isomerases catalyze isomerization between l -rhamnose (6-deoxy- l -mannose) and l -rhamnulose (6-deoxy- l -fructose), which is the first step in rhamnose catabolism. l -Rhamnose isomerase from Bacillus halodurans ATCC BAA-125 (BHRI) exhibits interesting characteristics such as high thermostability and selective substrate specificity. BHRI fused with an HHHHHH sequence was purified and crystallized in order to elucidate the molecular basis of its unique enzymatic properties. The crystals were grown by the hanging-drop vapour-diffusion method and belonged to the monoclinic space group P21, with unit-cell parameters a = 83.2, b = 164.9, c = 92.0,Å, , = 116.0°. Diffraction data were collected to 2.5,Å resolution. According to a Matthews coefficient calculation, there are four monomers in the asymmetric unit with a VM of 3.0,Å3,Da,1 and a solvent content of 59.3%. The initial structure of BHRI has been determined by the molecular-replacement method. [source] Crystallization and preliminary X-ray analysis of SDR-type pyridoxal dehydrogenase from Mesorhizobium lotiACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2010Huy Nhat Chu Pyridoxal 4-dehydrogenase from Mesorhizobium loti MAFF303099 was overexpressed in Escherichia coli. The recombinant selenomethionine-substituted enzyme was purified and crystallized by the sitting-drop vapour-diffusion method using PEG 4000 as precipitant. Crystals grew in the presence of 0.45,mM NAD+. The crystals diffracted to 2.9,Å resolution and belonged to the monoclinic space group P21, with unit-cell parameters a = 86.20, b = 51.11, c = 91.73,Å, , = 89.36°. The calculated VM values suggested that the asymmetric unit contained four molecules. [source] Crystallization and preliminary X-ray crystallographic analysis of the tetracycline-degrading monooxygenase TetX2 from Bacteroides thetaiotaomicronACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2010Gesa Volkers The flavin-dependent monooxygenase TetX2 from Bacteroides thetaiotaomicron confers resistance against tetracyclines in aerobically grown Escherichia coli. TetX2 modifies several tetracycline antibiotics by regioselective hydroxylation of the substrates to 11a-hydroxy-tetracyclines. X-ray diffraction data were collected from a native TetX2 crystal and a TetX2 crystal with incorporated selenomethionine to resolutions of 2.5 and 3.0,Å, respectively. The native crystal belonged to the triclinic space group P1, with unit-cell parameters a = 68.55, b = 80.88, c = 87.53,Å, , = 111.09, , = 98.98, , = 93.38°, whereas the selenomethionine-labelled TetX2 crystal belonged to the monoclinic space group P21, with unit-cell parameters a = 87.34, b = 68.66, c = 152.48,Å, , = 101.08°. [source] X-ray structure and characterization of carbamate kinase from the human parasite Giardia lambliaACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2010Andrey Galkin Carbamate kinase catalyzes the reversible conversion of carbamoyl phosphate and ADP to ATP and ammonium carbamate, which is hydrolyzed to ammonia and carbonate. The three-dimensional structure of carbamate kinase from the human parasite Giardia lamblia (glCK) has been determined at 3,Å resolution. The crystals belonged to the monoclinic space group P21, with unit-cell parameters a = 69.77, b = 85.41, c = 102.1,Å, , = 106.8°. The structure was refined to a final R factor of 0.227. The essentiality of glCK together with its absence in humans makes the enzyme an attractive candidate for anti- Giardia drug development. Steady-state kinetic rate constants have been determined. The kcat for ATP formation is 319 ± 9,s,1. The Km values for carbamoyl phosphate and ADP are 85 ± 6 and 70 ± 5,µM, respectively. The structure suggests that three invariant lysine residues (Lys131, Lys216 and Lys278) may be involved in the binding of substrates and phosphoryl transfer. The structure of glCK reveals that a glycerol molecule binds in the likely carbamoyl phosphate-binding site. [source] Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the collagen-binding region of RspB from Erysipelothrix rhusiopathiaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 2 2010Aribam Swarmistha Devi RspB is a surface adhesin of Erysipelothrix rhusiopathiae. A recombinant form of the collagen-binding region of this protein, RspB(31,348), has been overexpressed in Escherichia coli in native and selenomethionine-derivative forms and purified using affinity and gel-permeation chromatography. Thin plate-like crystals were obtained by the hanging-drop vapour-diffusion method using the same condition for both forms. The native crystals diffracted to a resolution of 2.5,Å using an in-house X-ray source, while the selenomethionine-derivative crystals diffracted to a resolution of 2.2,Å using synchrotron radiation. The crystals belonged to the monoclinic space group P21, with unit-cell parameters a = 46.19, b = 66.65, c = 101.72,Å, , = 94.11°. [source] Purification, crystallization and preliminary X-ray analysis of Enterococcus casseliflavus aminoglycoside-2,,-phosphotransferase-IVaACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2010Marta Toth The deactivation of aminoglycoside antibiotics by chemical modification is one of the major sources of bacterial resistance to this family of therapeutic compounds, which includes the clinically relevant drugs streptomycin, kanamycin and gentamicin. The aminoglycoside phosphotransferases (APHs) form one such family of enzymes responsible for this resistance. The gene encoding one of these enzymes, aminoglycoside-2,,-phosphotransferase-IVa [APH(2,,)-IVa] from Enterococcus casseliflavus, has been cloned and the protein (comprising 306 amino-acid residues) has been expressed in Escherichia coli and purified. The enzyme was crystallized in three substrate-free forms. Two of the crystal forms belonged to the orthorhombic space group P212121 with similar unit-cell parameters, although one of the crystal forms had a unit-cell volume that was approximately 13% smaller than the other and a very low solvent content of around 38%. The third crystal form belonged to the monoclinic space group P21 and preliminary X-ray diffraction analysis was consistent with the presence of two molecules in the asymmetric unit. The orthorhombic crystal forms of apo APH(2,,)-IVa both diffracted to 2.2,Å resolution and the monoclinic crystal form diffracted to 2.4,Å resolution; synchrotron diffraction data were collected from these crystals at SSRL (Stanford, California, USA). Structure determination by molecular replacement using the structure of the related enzyme APH(2,,)-IIa is proceeding. [source] Purification, crystallization and preliminary crystallographic analysis of the [NiFeSe] hydrogenase from Desulfovibrio vulgaris HildenboroughACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2009Marta Marques The [NiFeSe] hydrogenases belong to a subgroup of the [NiFe] proteins in which a selenocysteine is a ligand of the Ni. These enzymes demonstrate interesting catalytic properties, showing a very high H2 -producing activity that is sustained in the presence of low O2 concentrations. The purification, crystallization and preliminary X-ray diffraction analysis of the [NiFeSe] hydrogenase isolated from Desulfovibrio vulgaris Hildenborough are reported. Crystals of the soluble form of this hydrogenase were obtained using 20% PEG 1500 as a precipitant and belonged to the monoclinic space group P21, with unit-cell parameters a = 60.57, b = 91.05, c = 66.85,Å, , = 101.46°. Using an in-house X-ray diffraction system, they were observed to diffract X-rays to 2.4,Å resolution. [source] The Z isomer of 2,4-diaminofuro[2,3- d]pyrimidine antifolate promotes unusual crystal packing in a human dihydrofolate reductase ternary complexACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2009Vivian Cody The crystal structure of the ternary complex of human dihydrofolate reductase (hDHFR) with NADPH and the Z isomer of 2,4-diamino-5-[2-(2,-methoxyphenyl)propenyl]-furo[2,3- d]pyrimidine (Z1) shows that the Z isomer binds in the normal antifolate orientation in which the furo oxygen occupies the 8-amino position observed in the binding of 2,4-diaminopteridine antifolates such as methotrexate and with the methoxyphenyl moiety cis to and coplanar with the furo[2,3- d]pyrimidine ring. The hDHFR ternary complex crystallized in the orthorhombic space group P212121 and its structure was refined to 1.7,Å resolution. Although other hDHFR complexes crystallize in this space group, these data provide only the second example of an unusual packing arrangement in which the conserved active-site Arg70 forms a salt bridge to the side chain of Glu44 from a symmetry-related molecule. As a result, the conformations of Phe31 and Gln35 shift with respect to those observed in the structure of mouse DHFR bound to Z1, which crystallizes in the monoclinic space group P21 and shows that Gln35 interacts with Arg70. [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] Isolation, crystallization and preliminary X-ray analysis of the transamidosome, a ribonucleoprotein involved in asparagine formationACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 6 2009Marc Bailly Thermus thermophilus deprived of asparagine synthetase synthesizes Asn on tRNAAsnvia a tRNA-dependent pathway involving a nondiscriminating aspartyl-tRNA synthetase that charges Asp onto tRNAAsn prior to conversion of the Asp to Asn by GatCAB, a tRNA-dependent amidotransferase. This pathway also constitutes the route of Asn-tRNAAsn formation by bacteria and archaea deprived of asparaginyl-tRNA synthetase. The partners involved in tRNA-dependent Asn formation in T. thermophilus assemble into a ternary complex called the transamidosome. This particule produces Asn-tRNAAsn in the presence of free Asp, ATP and an amido-group donor. Crystals of the transamidosome from T. thermophilus were obtained in the presence of PEG 4000 in MES,NaOH buffer pH 6.5. They belonged to the primitive monoclinic space group P21, with unit-cell parameters a = 115.9, b = 214.0, c = 127.8,Å, , = 93.3°. A complete data set was collected to 3,Å resolution. Here, the isolation and crystallization of the transamidosome from T. thermophilus and preliminary crystallographic data are reported. [source] Expression, purification, crystallization and preliminary crystallographic analysis of laminin-binding protein (Lmb) from Streptococcus agalactiaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2009Preethi Ragunathan Laminin-binding protein (Lmb), a surface-exposed lipoprotein from Streptococcus agalactiae (group B streptococcus), mediates attachment to human laminin and plays a crucial role in the adhesion/invasion of eukaryotic host cells. However, the structural basis of laminin binding still remains unclear. In the context of detailed structural analysis, the lmb gene has been cloned, expressed in Escherichia coli, purified and crystallized. The crystals diffracted to a resolution of 2.5,Å and belonged to the monoclinic space group P21, with unit-cell parameters a = 56.63, b = 70.60, c = 75.37,Å, , = 96.77°. [source] Crystallization and crystallographic analysis of Bacillus subtilis xylanase CACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2009Franz J. St John The recent biochemical characterization of the xylanases of glycosyl hydrolase family 5 (GH 5) has identified a distinctive endo mode of action, hydrolyzing the ,-1,4 xylan chain at a specific site directed by the position of an ,-1,2-linked glucuronate moiety. Xylanase C (XynC), the GH 5 xylanase from Bacillus subtilis 168, has been cloned, overexpressed and crystallized. Initial data collection was performed and a preliminary model has been built into a low-quality 2.7,Å resolution density map. The crystals belonged to the primitive monoclinic space group P21. Further screening identified an additive that resulted in large reproducible crystals. This larger more robust crystal form belonged to space group P21212 and a resulting data set has been processed to 1.64,Å resolution. This will be the second structure to be solved from this unique xylanase family and the first from a Gram-positive bacterium. This work may help to identify the structural determinants that allow the exceptional specificity of this enzyme and the role it plays in the biological depolymerization and processing of glucuronoxylan. [source] | |||||||||||||