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Approximate Unit-cell Parameters (approximate + unit-cell_parameter)
Selected AbstractsCrystallization and preliminary X-ray analysis of NADP(H)-dependent alcohol dehydrogenases from Saccharomyces cerevisiae and Rana pereziACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2003Eva Valencia Different crystal forms diffracting to high resolution have been obtained for two NADP(H)-dependent alcohol dehydrogenases, members of the medium-chain dehydrogenase/reductase superfamily: ScADHVI from Saccharomyces cerevisiae and ADH8 from Rana perezi. ScADHVI is a broad-specificity enzyme, with a sequence identity lower than 25% with respect to all other ADHs of known structure. The best crystals of ScADHVI diffracted beyond 2.8,Å resolution and belonged to the trigonal space group P3121 (or to its enantiomorph P3221), with unit-cell parameters a = b = 102.2, c = 149.7,Å, , = 120°. These crystals were produced by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. Packing considerations together with the self-rotation function and the native Patterson map seem to indicate the presence of only one subunit per asymmetric unit, with a volume solvent content of about 80%. ADH8 from R. perezi is the only NADP(H)-dependent ADH from vertebrates characterized to date. Crystals of ADH8 obtained both in the absence and in the presence of NADP+ using polyethylene glycol and lithium sulfate as precipitants diffracted to 2.2 and 1.8,Å, respectively, using synchrotron radiation. These crystals were isomorphous, space group C2, with approximate unit-cell parameters a = 122, b = 79, c = 91,Å, , = 113° and contain one dimer per asymmetric unit, with a volume solvent content of about 50%. [source] Crystallization and preliminary X-ray analysis of substrate complexes of leucine dehydrogenase from Thermoactinomyces intermediusACTA CRYSTALLOGRAPHICA SECTION D, Issue 6-2 2002Tatyana A. Muranova Leucine dehydrogenase is an octameric enzyme which belongs to the superfamily of amino-acid dehydrogenases and catalyses the reversible oxidative deamination of leucine to 2-ketoisocaproate, with the corresponding reduction of the cofactor NAD+. Catalysis by this enzyme is thought to involve a large-scale motion of the enzyme's two domains between an `open' and `closed' form, with the latter representing a conformation of the enzyme in which the partners involved in the hydride-transfer reaction are appropriately positioned for catalysis. Whilst a structure for the open form of the enzyme has been determined, the nature of the closed form has yet to be observed. In order to trap a closed form, crystals of the complexes of leucine dehydrogenase from Thermoactinomyces intermedius with 2-ketoisocaproate and with 2-ketoisocaproate and NAD+ have been obtained by the hanging-drop vapour-diffusion method using PEG 4000 as a precipitant. The crystals of the binary complex with 2-ketoisocaproate belong to space group P212121, with approximate unit-cell parameters a = 106, b = 118, c = 320,Å and an octamer in the asymmetric unit, corresponding to a VM of 3.1,Å3,Da,1. The crystals of the non-productive ternary complex belong to space group P61 or P65, with approximate unit-cell parameters a = b = 117, c = 502,Å and an octamer in the asymmetric unit, corresponding to a VM of 3.0,Å3,Da,1. These crystals diffract X-rays on a synchrotron-radiation source to at least 2.8 and 3.3,Å resolution, respectively, and are suitable for a full structure determination. [source] Purification, crystallization and quaternary structure analysis of a glycerol dehydrogenase S305C mutant from Bacillus stearothermophilusACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2001Jacky Burke Bacillus stearothermophilus glycerol dehydrogenase (GlyDH) is a 39.5,kDa molecular weight metalloenzyme which catalyzes the oxidation of glycerol to dihydroxyacetone with the concomitant reduction of NAD+ to NADH. Despite its classification as a member of the `iron-containing' polyol dehydrogenase family, studies on recombinant B. stearothermophilus GlyDH have shown this enzyme to be Zn2+ -dependent. Crystals of a S305C GlyDH mutant were obtained by the hanging-drop vapour-diffusion method, using ammonium sulfate and PEG 400 as precipitating agents, in the presence and absence of NAD+. The crystals belong to space group I422, with approximate unit-cell parameters a = b = 105, c = 149,Å and one subunit in the asymmetric unit, corresponding to a packing density of 2.6,Å3,Da,1. The crystals diffract X-rays to at least 1.8,Å resolution on a synchrotron-radiation source. Determination of the structure will provide insights into the key determinations of catalytic activity of this class of enzymes, for which no structures are currently available. [source] Crystallization and preliminary crystallographic analysis of nosiheptide-resistance methyltransferase from Streptomyces actuosus in complex with SAMACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2010Huirong Yang Nosiheptide-resistance methyltransferase (NSR) methylates 23S rRNA at the nucleotide adenosine 1067 in Escherichia coli and thus contributes to resistance against nosiheptide, a sulfur-containing peptide antibiotic. Here, the expression, purification and crystallization of NSR from Streptomyces actuosus are reported. Diffracting crystals were grown by the hanging-drop vapour-diffusion method in reservoir solution consisting of 0.35,M ammonium chloride, 24%(w/v) PEG 3350, 0.1,M MES pH 5.7 at 293,K. Native data have been collected from the apo enzyme and a SAM complex, as well as apo SeMet SAD data. The diffraction patterns of the apo form of NSR, of NSR complexed with SAM and of SeMet-labelled NSR crystals extended to 1.90, 1.95 and 2.25,Å resolution, respectively, using synchrotron radiation. All crystals belonged to space group P21, with approximate unit-cell parameters a = 64.6, b = 69.6, c = 64.9,Å, , = 117.8°. [source] Purification, crystallization and preliminary X-ray diffraction analysis of human Gadd45,ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2008Wenzheng Zhang Gadd45, MyD118 and CR6 (also termed Gadd45,, Gadd45, and Gadd45,, respectively) comprise a family of proteins that play important roles in negative growth control, maintenance of genomic stability, DNA repair, cell-cycle control and apoptosis. Recombinant human Gadd45, and its selenomethionine derivative were expressed in an Escherichia coli expression system and purified; they were then crystallized using the hanging-drop vapour-diffusion method. Diffraction-quality crystals were grown at 291,K using PEG 3350 as precipitant. Using synchrotron radiation, the best diffraction data were collected to 2.3,Å resolution for native crystals at 100,K; selenomethionyl derivative data were collected to 3.3,Å resolution. All the crystals belonged to space group I213, with approximate unit-cell parameters a = b = c = 126,Å. 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