首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
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   

2.
Crystals of recombinant human interleukin 10 have been grown from solutions of ammonium sulfate. The crystals are tetragonal, space group P41212 or P43212; the unit cell axes are a = 36.5 Å and c = 221.9 Å. There is the equivalent of one polypeptide chain in the asymmetric unit. The crystals are stable to X-rays and diffract to at least 2.5 Å resolution. © 1995 Wiley-Liss, Inc.  相似文献   

3.
Rat catechol O-methyltransferase cDNA was introduced into an E. coli expression vector pKEX14, which utilizes the inducible T7 promoter. Active and soluble recombinant catechol O-methyltransferase was produced in bacteria and purified to electrophoretic homogeneity by chromatographic procedures. The purified enzyme has been crystallized by the method of vapor diffusion using polyethylene glycol as precipitant. The space group is P3(1)21 or P3(2)21 with a = b = 51.3 A and c = 168.5 A and one molecule in the asymmetric unit. The crystals diffract beyond 3.2 A and are suitable for three-dimensional X-ray structure determination.  相似文献   

4.
Crystals of recombinant bacterial nucleoside deoxyribosyltransferase have been grown from solutions of ammonium sulfate. The crystals are cubic, space group I23 or I2(1)3; the axial length is 151.1(2) A. The crystals are stable to x-rays for at least 5 days and diffract beyond 2.8-A resolution. It appears that the molecule, which is a hexamer, utilizes the symmetry of the space group, resulting in two or three subunits per asymmetric unit.  相似文献   

5.
Two different forms of crystals (potentially) suitable for x-ray structure analysis were obtained for recombinant human interleukin-2 (IL-2) using ammonium sulfate as a precipitant in the pH range of 6.3-7.3 (in the case of hexagonal bipyramidal crystals) and 4.5-5.5 (in the case of plate crystals). The hexagonal bipyramidal crystal belongs to a hexagonal space group P6(2)22 or P6(4)22 with a = b = 105.8 A and c = 122.2 A. The crystal diffracts up to 3.4 A resolution and contains 2 or 3 IL-2 molecules in an asymmetric unit. The plate crystal belongs to an orthorhombic space group P2(1)2(1)2 with a = 47.9 A, b = 79.6 A, and c = 31.9 A. The crystal diffracts up to 2.5 A resolution and contains only 1 IL-2 molecule in an asymmetric unit. These facts reconfirmed crystallographically the high homogeneity of the present preparation of human recombinant IL-2.  相似文献   

6.
Bipyramidal crystals of the recombinant calmodulin from Trypanosoma brucei rhodesiense were obtained by vapor diffusion against 55% (v/v) 2-methyl-2,4-pentanediol in 0.05 M cacodylate buffer, pH 5.6. When few nucleation events occurred, crystals grew to 0.25 × 0.25 × 1.20 mm. The space group of the crystal is I4122, with unit cell dimensions a = b = 56.88 Å, c = 230.11 Å, α = β = γ = 90°, z = 16. The molecular mass and volume of the unit cell suggest that there is one molecule in the asymmetric unit. The I/σ(I) ratio for data at 3.0 Å resolution was 3.67, indicating that the final structure can be refined at higher resolution. Molecular replacement methods and the PC-refinement technique have not yet yielded the structure under a variety of search conditions. We are currently investigating the multiple isomorphous replacement approach to determine this crystal structure. © 1995 Wiley-Liss, Inc.  相似文献   

7.
Human factor D, an essential enzyme of the alternative pathway of complement activation, has been crystallized. Crystals were grown by vapor diffusion using polyethylene glycol 6000 and NaCl as precipitants. The factor D crystals are triclinic and the space group is P1 with unit cell dimensions a = 40.8 A, b = 64.7 A, c = 40.3 A, alpha = 101.0 degrees, beta = 109.7 degrees, gamma = 74.3 degrees. The unit cell contains two molecules of factor D related by a non-crystallographic 2-fold axis. The crystals grow to dimensions of 0.8 mm x 0.5 mm x 0.2 mm within five days, are stable in the X-ray beam and diffract beyond 2.5 A.  相似文献   

8.
Recombinant murine interferon-beta produced in Escherichia coli was purified and crystallized in an orthorhombic space group C222(1) with a = 61.67 A, b = 55.62 A, and c = 92.16 A. The crystals with a slight tendency for orientational disorder around the c axis diffract at least up to 3.3-A resolution. The crystallizability and the fact that the crystallographic asymmetric unit contains only one molecule of murine interferon-beta strongly indicate that the present preparation (Matsuda, S., Utsumi, J., and Kawano, G. (1986) J. Interferon Res., in press) of recombinant murine interferon-beta is predominantly homogeneous with respect to chemical, tertiary, and quaternary structures.  相似文献   

9.
10.
Transglutaminases(TGases; protein-glutamine-glutamyl-transferases) are a large family of calcium-dependent acyl-transfer enzymes that catalyze the formation of covalent cross links in proteins. Of these, the "epidermal" or "hair follicle" TGase 3 isoform is critically involved in barrier formation in epithelia. It is a zymogen, requiring proteolytic activation to achieve maximal specific activity. In order to understand its structure and function, we have devised methods for the rapid large-scale expression of the TGase 3 zymogen in the baculovirus system, and here we describe the purification of the zymogen and activated forms. We describe methods for the formation of high-quality, well-diffracting crystals within 3-5 days, using both dioxane and beta-octylglucoside to overcome severe twinning problems. The crystal of the zymogen belongs to the triclinic space group P1 and diffracts to 2.2-A resolution, and the crystal of the active form belongs to the P2(1) space group at 2.7-A resolution.  相似文献   

11.
Crystals of a sarcoplasmic Ca(2+)-binding protein from the protochordate amphioxus have been grown from solutions of ammonium sulfate. The crystals are orthorhombic, space group C222(1), with unit cell axes a = 59.6(1) A, b = 81.3(1) A and c = 82.4(1) A. There is one molecule in the asymmetric unit. The crystals diffract beyond 2.5 A and show less than 20% decline in diffraction intensities after a three day exposure to X-rays from a laboratory rotating anode source.  相似文献   

12.
Crystals of Cladosporium acid protease have been grown from solutions of polyethylene glycol. The crystals are orthorhombic, space group, P212121, with alpha = 136.5(7) A, b = 109.4(5) A, and c = 87.7(4) A. There are four acid protease molecules/asymmetric unit. The crystals are quite stable to x-rays and diffract beyond 3.0-A resolution.  相似文献   

13.
Recombinant cutinase from Fusarium solani pisi is expressed and excreted with very high yields in Escherichia coli cultures. Cutinase was crystallized at 20 degrees C using the vapour diffusion technique, with polyethylene glycol 6000 as precipitant. Best crystals were obtained at pH 7.0 with polyethylene glycol 6000 as precipitant. Best crystals were obtained at pH 7.0 with polyethylene glycol at 15 to 20%. They are monoclinic, with space group P2(1) and cell dimensions a = 35.1 A, b = 67.4 A, c = 37.05 A and beta = 94.0 degrees; they diffract beyond 1.5 A resolution. The asymmetric unit contains one molecule of 22,000 Da (Vm = 1.98 A3/Da; 38% water).  相似文献   

14.
Soybean lipoxygenase 1 has been crystallized by the vapor diffusion method in 8-10% polyethylene glycol (average Mr 3400), 0.2 M sodium acetate buffer, pH 5.2-5.6, at a protein concentration of 6-12 mg/ml. Microseeding was employed to obtain growth of large single crystals. The crystals, which diffract to at least 2.2-A spacings, are monoclinic and of space group P2(1). Cell constants are: a = 95.4, b = 94.2, and c = 50.4 A and beta = 91.4 degrees. The calculated value of Vm (2.41 A3/Da) is consistent with the probable presence of one molecule of lipoxygenase/crystallographic asymmetric unit (Z = 2).  相似文献   

15.
Recombinant pentalenene synthase, a 42.5-kDa sesquiterpene cyclase originally isolated from Streptomyces UC5319 and cloned in Escherichia coli, has been crystallized in space group P6(3) with unit cell dimensions a = b = 183.5 A and c = 56.5 A. Hexagonal prismatic crystals, approximately 0.2 x 0.2 x 0.3 mm, diffract to approximately 2.9 A resolution using monochromatic synchrotron radiation. From the universal (and achiral) building block, farnesyl pyrophosphate, pentalenene synthase catalyzes the formation of four stereocenters in the construction of the three fused five-membered rings of pentalenene; this novel sesquiterpene is a precursor to the pentalenolactone family of antibiotics.  相似文献   

16.
Reproducible conditions have been established for the crystallization of recombinant bovine immune interferon. Two cystalline forms of this protein were obtained. A tetragonal form, space group P422, with unit cell dimensions a = b = 59.0 A and c = 125.7 A and an orthorhombic form, space group P2(1)2(1)2(1), with unit cell dimensions a = 42.80 A, b = 79.90 A and c = 85.64 A were obtained under similar crystallization conditions. The orthorhombic form diffracts to 2.6 A resolution, contains a single interferon dimer in the asymmetric unit of structure and is suitable for X-ray diffraction analysis.  相似文献   

17.
Crystals of recombinant human angiogenin have been grown from solutions containing sodium potassium tartrate and polyethylene glycol as precipitants. They belong to the space group C222(1) (a = 83.36 A, b = 120.64 A, c = 37.72 A) and contain a single molecule in the asymmetric unit. The crystals diffract to at least 2.3 A resolution and are suitable for three-dimensional X-ray structural analysis.  相似文献   

18.
The FAD-containing enzyme lipoamide dehydrogenase (EC 1.6.4.3. NADH: lipoamide oxidoreductase) of Azotobacter vinelandii has been crystallized from polyethylene glycol solutions. The space group is P2(1)2(1)2(1) with one dimer in the asymmetric unit. The cell dimensions are: a = 64.2, b = 83.8, c = 193 A. X-ray reflections extend to at least 2.2 A resolution.  相似文献   

19.
Porphobilinogen deaminase, the polymerase that catalyses the synthesis of preuroporphyrinogen, the linear tetrapyrrole precursor of uroporphyrinogen III, has been crystallized from sodium acetate buffer with polyethylene glycol 6000 as precipitant. The crystals are orthorhombic and the space group is P2(1)2(1)2, with unit cell dimensions a = 88.01 A, b = 75.86 A, c = 50.53 A and alpha = beta = gamma = 90 degrees, indicating a single molecule of 34 kDa in the asymmetric unit. The crystals grow to dimensions of 1 mm x 2 mm x 0.5 mm within two weeks in the dark and are stable in the X-ray beam for at least 40 hours. Diffraction data beyond 1.7 A resolution, observed with a synchrotron radiation source, indicate that a high resolution structure analysis is feasible.  相似文献   

20.
Crystals of uridine phosphorylase from Escherichia coli K12 have been grown from solutions of polyethylene glycol 4000. The crystals are trigonal, space group R3; the hexagonal axes are a = 154.4 A and c = 49.4 A. The crystals are quite stable to x-rays and diffract beyond 2.6 A resolution. It appears that the molecule is a hexamer with a subunit molecular weight of 27,500 and utilizes the 3-fold symmetry of the space group, resulting in two subunits/asymmetric unit.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号