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1.
A tetra-heme and an octa-heme cytochrome c3 from the sulfate bacterium Desulfovibrio gigas have been crystallized. Diffraction quality crystals of the tetra-heme cytochrome are obtained from solution by the addition of polyethylene glycol at pH 6.5. The crystals are orthorhombic, space group P2(1)2(1)2 with unit cell parameters a = 42.27 A, b = 52.54 A and c = 52.83 A. The octa-heme cytochrome crystals develop from low ionic strength solutions of phosphate or Tris-Cl in the pH range 6.2-7.6. The crystals belong to the trigonal system, space group P3(1) or the enantiomorph P3(2), with unit cell parameters a = b = 57.4 A, c = 97.3 A, gamma = 120 degrees. Single crystal diffraction studies of the structures of these two low-potential cytochromes are in progress.  相似文献   

2.
The histidine-containing phosphocarrier protein (HPr) from Bacillus subtilis has been crystallized. Two of the site-directed mutants aimed at probing function produce crystals suitable for X-ray studies. The mutant in which His15 is substituted by an alanyl residue crystallizes from ammonium sulfate solution in space group P3(1)21 or P3(2)21, with unit cell dimensions: a = b = 47.3 A; c = 61.5 A. These crystals diffract to at least 1.8 A resolution. The mutant in which Ser46 is substituted by an aspartyl residue crystallizes from polyethylene glycol 4000 solution in space group P2(1), with unit cell dimensions: a = 49.4 A; b = 25.6 A; c = 60.3 A; beta = 109 degrees. These crystals diffract to at least 2.0 A resolution.  相似文献   

3.
Good diffracting crystals of 3-ketoacylCoA thiolase (EC 2.3.1.16) from yeast Saccharomyces cerevisiae have been obtained. The crystals diffract to at least 2.4 A. The space group of these crystals is P2(1)2(1)2(1), with cell dimensions a = 71.8 A, b = 93.8 A and c = 119.9 A. There is one dimer per asymmetric unit.  相似文献   

4.
The crystals of a complex between ribonuclease Ms, the extracellular ribonuclease from Aspergillus saitoi, and 3'-guanylic acid were obtained from 2-methyl-2,4-pentanediol solution by vapor diffusion technique in the hanging drop mode. The crystals belong to orthorhombic space group P2(1)2(1)2(1) with dimensions a = 47.0 A, b = 62.8 A, c = 37.9 A. The crystals diffract strongly up to at least 2.0 A resolution.  相似文献   

5.
Proteins L30 and S5 from the 50 S and 30 S subunits, respectively, of the Bacillus stearothermophilus ribosome have been crystallized. L30 crystals are tetragonal and the space group is P4(1)2(1)2 (or P4(3)2(1)2) with cell dimensions a = b = 46.3 A and c = 61.4 A. S5 crystals are trigonal with the space group P3(1)21 (or P3(2)21) and cell dimensions a = b = 59.3 A and c = 109.8 A. In both cases, there appears to be a single molecule in the asymmetric unit.  相似文献   

6.
Large single crystals of a glycopeptide resistance protein encoded by the SH-ble gene from Streptoalloteichus hindustanus have been grown using vapor diffusion techniques with ammonium sulfate as the precipitant. The diffraction pattern extends to 2.0 A resolution. The crystals belong to space group P4(1)2(1)2 or P4(3)2(1)2 and have unit cell dimensions of a = 48.8 A and c = 112.5 A.  相似文献   

7.
Crystals of type I cAMP-dependent protein kinase regulatory subunit have been grown from solutions of ammonium sulfate. The crystals are square bipyramids, space group P4(1)2(1)2 (P4(3)2(1)2), with a = b = 106.9 +/- 0.6 A and c = 212.4 +/- 1.0 A. There are two dimers of the regulatory subunit/crystallographic asymmetric unit. The crystals are stable for 3-4 days in the x-ray beam and diffract to at least 3.5-A resolution.  相似文献   

8.
Crystals of the tetrameric xylose isomerase from Streptomyces violaceoniger have been examined by x-ray analysis. Octahedral crystals with a maximum dimension of 0.7 mm were grown from ammonium sulfate solution. They possess the symmetry of P4(1)2(1)2 or P4(3)2(1)2 space groups, which are crystallographically indistinguishable. The unit cell dimensions are a = b = 140 A and c = 134 A. There is one tetramer of molecular weight 160,000 per asymmetric unit. The crystals diffract to 2.2 A.  相似文献   

9.
Purple acid phosphatase from red kidney bean has been crystallized from ammonium sulfate solutions in the pH range from 3.5 to 5.5. The crystal form is tetragonal bipyramidal and the largest crystals grew up to 2.0 mm long. Systematic absences indicate one of the enantiomorphic space groups P4(1)2(1)2 (92) or P4(3)2(1)2 (96) with cell dimensions a = b = 104.1(1) A and c = 308.7(2) A. The asymmetric unit contains one dimer with Mr of 110,700, determined by ultraviolet-laser desorption mass spectrometry. The crystals, with a salt-free density of 1.12 g/cm3 and a water content of 67%, diffract to 3.5 A.  相似文献   

10.
Crystals of recombinant human interleukin 4 have been grown from solutions of ammonium sulfate. The crystals are tetragonal, space-group P4(1)2(1)2 or P4(3)2(1)2; the unit cell axes are a = 92.2(1) A and c = 46.4(1) A. The crystals are stable to X-rays for at least three days and diffract beyond 2.8 A resolution. The crystals contain approximately 63% solvent, assuming there is one molecule in the asymmetric unit.  相似文献   

11.
Crystals of the mouse major urinary protein (MUP) and rat alpha-2u globulin (AMG) have been grown from solutions of polyethylene glycol 3350 and CdCl2, respectively. The crystals differ both in their morphologies and space groups but have very similar unit cell sizes. AMG crystallized in P2(1) (a = 56.6 A, b = 103.8 A, c = 62.7 A, beta = 95.1 degrees) with four subunits/asymmetric unit, while MUP gave crystals in P4(1)2(1)2 or P4(3)2(1)2 (a = 57.3 A, c = 109.9 A) with one subunit/asymmetric unit. Both crystal forms diffract beyond 2.8 A resolution.  相似文献   

12.
Single crystals of the catalytic domain of Cex, an exo-beta-1,4-glucanase and beta-1,4-xylanase from the cellulolytic bacterium Cellulomonas fimi, have been grown in the presence of polyethylene glycol 4000 using the vapour diffusion technique. The crystals, which diffract to better than 2.0 A resolution, belong to space group P4(1)2(1)2 or P4(3)2(1)2 and have cell constants: a = b = 88.21 A, c = 81.10 A; alpha = beta = gamma = 90 degrees.  相似文献   

13.
The amino terminal half of human lactoferrin (LfN) produced from transfected baby hamster kidney cells has been crystallized in its iron-saturated and iron-free forms. The crystals of glycosylated LfN and deglycosylated LfN are monoclinic, space group C2, with cell dimensions a = 133.0 A, b = 58.3 A, c = 58.3 A, alpha = 90.0 degrees, beta = 114.7 degrees, gamma = 90.0 degrees, and one molecule per asymmetric unit. Crystals of apo LfN have also been prepared using deglycosylated protein. These crystals are tetragonal, space group P4(1)2(1)2 (or P4(3)2(1)2), with cell dimensions of a = b = 58.4 A and c = 217.2 A and one molecule per asymmetric unit. Both the iron-saturated and the iron-free crystals are suitable for high resolution X-ray analysis.  相似文献   

14.
Single crystals of a bovine neurophysin II-oxytocin complex have been obtained using (NH4)2SO4 as the precipitating agent. The crystals diffract to at least 2.7 A resolution, belong to Laue group 4/mmm and exhibit systematic absences consistent with either space group P4(1)2(1)2 or P4(3)2(1)2. The cell dimensions are a = b = 69.07 A and c = 113.26 A. The crystals contain one neurophysin-oxytocin dimer per asymmetric unit. Based on a Vm of 2.9 A3/Da, the solvent content is calculated to be 58%. Chromatographic analysis of the dissolved crystals suggests the presence of three oxytocin molecules per neurophysin dimer.  相似文献   

15.
A new crystal form of ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39) from Nicotiana tabacum has been obtained at alkaline pH with polyethylene glycol 8000 in the presence of a non-ionic detergent, beta-octyl glucoside. The crystals are grown at room temperature by the hanging-drop vapor diffusion technique from a protein solution containing enzyme complexed with CO2, Mg2+, and the transition state analog 2-C-carboxy-D-arabinitol-1,5-bisphosphate. The crystals belong to the the space group P3(1)21 (or P3(2)21) with the cell parameters a = 204.6 A, and c = 117.4 A (1 A = 0.1 nm). The asymmetric unit contains half (L4S4: L, large subunit, 53,000 Mr; S, small subunit, 15,000 Mr) of a hexadecameric molecule (L8S8, 540,000 Mr). The crystals diffract to at least 2.6 A Bragg spacing and are suitable for X-ray structure determination.  相似文献   

16.
alpha-Amylase from Bacillus licheniformis has been crystallized by the hanging-drop vapor diffusion method in the presence of calcium ions using ammonium sulfate as precipitant. The crystals are tetragonal, belonging to the space group P4(1)2(1)2 (or P4(3)2(1)2), with unit cell dimensions of a = 119.9 and c = 85.4 A. The asymmetric unit contains one molecule of alpha-amylase, with a crystal volume per protein mass (VM) of 2.78 A3/Da. The crystals diffract to better than 2.0 A Bragg spacing when exposed to synchrotron X-rays and they are reasonably stable in the X-ray beam. Thus the crystals are suitable for structure determination at high resolution by X-ray methods.  相似文献   

17.
Three crystalline polymorphs of the helical decapeptide, Boc-Aib-Ala-Leu-Ala-Leu-Aib-Leu-Ala-Leu-Aib-OMe, have been obtained. Antiparallel helix aggregation is observed in crystals grown from methanol (A), while completely parallel packing is observed in crystals from isopropanol (B) or an ethylene glycol-ethanol mixture (C). Crystals B and C are very similar in molecular conformation and packing. The packing motifs in crystals A and B consist of rows of parallel molecules, with an almost identical arrangement in both crystals. In crystal A, adjacent rows assemble with the helix axes pointed in opposite directions, whereas in crystal B all rows assemble with helix axes pointed in the same direction. Electrostatic interactions between helix dipoles do not appear to be a major determinant of packing modes. The structures also do not provide a ready rationalization of packing preferences in terms of side-chain interactions or solvation. The alpha-helix of the peptide in crystal A has seven 5----1 hydrogen bonds; the helix in crystal B is a mixed 3(10)/alpha-helix. The crystal parameters are as follows. Crystal A: C51H92N10O13.CH3OH, space group P2(1) with a = 10.498 (1) A, b = 18.189 (3) A, c = 16.475 (3) A, beta = 99.28 (1) degree, Z = 2, R = 9.6% for 1860 data. Crystal B: C51H92N10O13.C3H7OH, space group P2(1) with a = 10.534 (1) A, b = 28.571 (4) A, c = 11.055 (2) A, beta = 95.74 (1) degree, Z = 2, R = 6.5% for 3251 data. Crystal C: C51H92N10O13.C2H5OH, space group P2(1), with a = 10.450 (1) A, b = 28.442 (5) A, c = 11.020 (2) A, beta = 95.44(1) degree, Z = 2, R = 14.8% (isotropic) for 1948 data.  相似文献   

18.
Preliminary x-ray data have been obtained from large single crystals of pig kidney fructose-1,6-bisphosphatase, grown from polyethylene glycol. The crystals have the symmetry of space group P3(1)21 or its enantiomorph P3(2)21, contain two subunits of the 146,000-dalton tetramer/asymmetric unit, and diffract to 2.9-A resolution on still photographs. The unit cell dimensions are a = b = 132.5 A and c = 68.0 A. Small single crystals have been grown in the presence of the inhibitor fructose 2,6-bisphosphate, with and without the allosteric effector AMP added. Crystals grown in the presence of both ligands are isomorphous with native crystals and generate diffraction patterns that show significant intensity changes.  相似文献   

19.
Single crystals of ribonuclease Mc, a new class of plant ribonuclease from the seeds of the bitter gourd, were obtained from solutions of polyethylene glycol 8000 by the hanging-drop vapour diffusion method. The crystals belong to the orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 67.28 A, b = 75.21 A, c = 38.54 A. The assumption of one monomer per asymmetric unit gives rise to a Vm value of 2.29 A3/Da. The crystals diffract beyond 2.0 A resolution and are suitable for high resolution X-ray structure analysis.  相似文献   

20.
X-ray quality crystals of a soluble murine class I H-2Kb molecule complexed with three different peptide antigens were grown in several forms by streak seeding and macroseeding methods. Co-crystals with VSV-8 (RGYVYGQL), OVA-8 (SIINFEKL) and SEV-9 (FAPGNYPAL) peptides were grown either from NaH2PO4/HPO4 or from polyethylene glycol 4000 within the pH range 5.0 to 7.5, with the use of 4-methyl-2-pentane diol (MPD) as an additive. The VSV-8 crystals grew in space groups P1, with cell dimensions a = 63.1 A, b = 69.1 A, c = 72.0 A, alpha = 89.9 degrees, beta = 77.1 degrees, gamma = 123.3 degrees and P2(1)2(1)2, with a = 138.1 A, b = 88.6 A, c = 45.7 A, and diffract to 2.9 and 2.3 A, respectively. Crystals of the SEV-9 complex grew from similar crystallization conditions to those of the orthorhombic VSV-8 complex with similar cell parameters and diffract to at least 2.5 A resolution. Crystals of the OVA-8 complex were obtained from either phosphate (space group C2, a = 118.7 A, b = 61.6 A, c = 85.3 A, beta = 108.4 degrees) or polyethylene glycol (space group P1, a = 64.5 A, b = 71.0 A, c = 66.3 A, alpha = 89.7 degrees, beta = 95.7 degrees, gamma = 123.3 degrees) and diffract to 3 A resolution. The crystallization procedures used here significantly increased the rate and production of X-ray quality crystals.  相似文献   

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