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1.
Two crystal forms of the cytochrome c2 isolated from Rhodopseudomonas capsulata have been obtained. One crystal form (type I), grown from ammonium sulfate solutions at pH 7.5, belongs to the space group R32 with unit cell dimensions of a = b = 100.0 A, and c = 162.2 A in the hexagonal setting. These crystals most likely contain two molecules in the asymmetric unit. The other crystal form (type II) was obtained from polyethylene glycol 6000 solutions at pH 6.5. Type II crystals belong to the space group P3(1)21 or P3(2)21 with one molecule per asymmetric unit and unit cell dimensions of a = b = 52.4 A, and c = 87.9 A. Both crystal forms diffract to at least 1.8 A resolution and appear to be resistant to radiation damage.  相似文献   

2.
Crystals have been grown of the V(1)-ATPase sector of the V-type ATP synthase complex (V(0)V(1)) from the thermophilic eubacterium Thermus thermophilus HB8. These crystals are grown by the vapor diffusion method in the presence of 5 mM Mg-ADP, from solutions containing 100 mM sodium acetate and 2 M sodium formate, pH 5.5. The crystals diffracted X rays beyond 3.4 A in resolution on a synchrotron radiation source. The crystals belong to the trigonal space group P3, with unit cell dimensions of a = b = 89.0 A, c = 179.2 A, and gamma = 120 degrees. The unit cell presumably contains one molecule of V(1)-ATPase and the V(m) value is calculated as 3.0 A(3)/Da.  相似文献   

3.
The Cu,Zn superoxide dismutase (Cu,Zn SOD) originally isolated from the periplasmic space of Escherichia coli has been cloned and overexpressed in the E. coli strain BMH 71/18. The protein has been purified as a single component of 17,000 Da, corresponding to one subunit of the common dimeric eukaryotic Cu,Zn SODs. Large crystals of the purified protein have been grown in the presence of polyethylene glycol 4,000 at pH 8.5; the crystals belong to the monoclinic space group P2(1), with unit cell constants a = 33.1 A, b = 52.6 A, c = 43.3 A, beta = 111.4 degrees. One SOD subunit is contained in the asymmetric unit, yielding a Vm value of 2.1 A3/Da; the crystals diffract X-rays beyond 2.0 A resolution.  相似文献   

4.
Well-ordered single crystals have been grown for a mannose-specific lectin from snowdrop (Galanthus nivalis) bulbs in the presence of methyl-alpha-D-mannoside. The space group symmetry is consistent with the orthorhombic space group P2(1)2(1)2(1). The unit cell parameters are a = 140.0 A, b = 64.7 A, c = 62.0 A. The asymmetric unit can accommodate a tetramer. The functional molecule (50,000 daltons) consists of four identical subunits and is highly specific for alpha 1,3-linked mannose oligosaccharides.  相似文献   

5.
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   

6.
Crystals of pyridoxal kinase from sheep brain have been grown from solutions of ammonium sulfate or Na+/K+ phosphate. The crystals are trigonal, space group P3(1)21 with axes a = b = 102.2 A and c = 58.5 A. The crystals are quite stable to x-rays and diffract at 2.2-A resolution. This macromolecule is a 80,000-kDa dimer and utilizes the 2-fold symmetry of the space group, resulting in one subunit/asymmetric unit.  相似文献   

7.
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   

8.
Single crystals of recombinant Escherichia coli ornithine transcarbamoylase suitable for x-ray analysis have been grown from polyethylene glycol and 2-methyl-2,4-pentanediol. The space group has been determined as P3(1) or P3(2), with one protein trimer of three identical 36.8-kDa subunits in the asymmetric unit. The unit cell dimensions are a = b = 105.1 A and c = 87.8 A. The crystals diffract well to 3-A resolution and are quite resistant to radiation damage. Single crystals have also been grown of a genetically engineered site-specific mutant for which the replacement of an arginine (Arg-57) to a glycine has been shown to not only drastically affect the enzyme activity but also its kinetic mechanism (Kuo, L. C., Miller, A. W., Lee, S., and Kozuma, C. (1988) Biochemistry 27, 8823-8832). The crystals of the Arg-57----Gly mutant protein are isomorphous to those of the wild type. Crystal soaking experiments using both wild-type and Arg-57----Gly crystals in the presence of various ligands have provided evidence of specific conformational changes upon substrate binding which supports our previous kinetic and spectroscopic observations.  相似文献   

9.
Crystals of the DNA glucosylating enzyme beta-glucosyltransferase from phage T4 have been grown in the presence of uridine diphosphate glucose. The crystals are orthorhombic, space group P2(1)2(1)2 with a = 148.3 A, b = 52.6 A, c = 52.6 A. The assumption of one monomer of Mr 40,000 per asymmetric unit gives rise to a Vm of 2.56 A 3/dalton. The crystals diffract to beyond 2.7 A and are suitable for X-ray structure analysis.  相似文献   

10.
Bacillus stearothermophilus lactate dehydrogenase was purified from an overexpressing Escherichia coli cell line. The enzyme has been crystallized in several different forms. All of these crystal forms were grown in the presence of NADH, sodium oxamate and fructose 1,6-bisphosphate. Three crystal forms have been characterized, an orthorhombic P2(1)2(1)2 (type III, a = 86 A, b = 105 A, c = 136 A) and two monoclinic P21 forms (type IV, a = 85 A, b = 118 A, c = 136 A, beta = 96 degrees; type V, a = 112 A, b = 85 A, c = 136 A, beta = 91 degrees). Precession photographs from these crystal forms are very alike, suggesting the molecular packing to be similar in all three forms. The P21 type IV crystals diffract to beyond 2 A spacing and are stable to irradiation with X-rays. A complete medium-resolution (4.7 A) dataset has been collected from a single crystal using synchrotron radiation. Rotation function studies with these data show the two tetramers of the asymmetric unit to be in very similar orientations. Higher-resolution data are being collected.  相似文献   

11.
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   

12.
Crystals of the calcium-containing lysozyme from horse milk have been grown by precipitation with sodium phosphate. The crystals are orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 53.2, b = 57.1, and c = 38.2 A and contain a single molecule in the asymmetric unit. The crystals are suitable for high resolution x-ray structural analysis.  相似文献   

13.
Crystals suitable for X-ray diffraction analysis of both glycosylated and non-glycosylated forms of a barley peroxidase have been grown. The crystals of the glycosylated peroxidase have been grown by the hanging drop vapour diffusion method using polyethylene glycol 4000 as the precipitant in the presence of n-propanol and potassium iodide at pH 8.5. The crystals are needles belonging to the orthorhombic spacegroup P2(1)2(1)2(1) with unit cell dimensions a = 62.95 A, b = 66.24 A and c = 70.78 A. There is one barley peroxidase molecule in the asymmetric unit. The crystals contain approximately 38% solvent and appear to be stable to lengthy X-ray exposure. They diffract to beyond 1.9 A.  相似文献   

14.
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   

15.
The complete amino acid sequence of acidic Agkistrodon halys blomhoffii phospholipase A2 has been redetermined by a combination of manual and automatic Edman degradations. Acidic A. halys blomhoffi phospholipase is a single polypeptide chain consisting of 122 amino acids and is highly homologous in sequence with corresponding regions of phospholipase A2 from a variety of sources. Prism crystals of acidic A. halys blomhoffii phospholipase have been reproducibly grown from 2-methyl-2,4-pentanediol solution adjusted to pH 8.0 with 50 mM Tris-HCl buffer in the presence of 10 mM CaCl2. The crystals belong to space group P6(1)22 or P6(5)22 with hexagonal unit cell dimensions of a = b = 76.22 A and C = 76.56 A. One molecule occupies the asymmetric unit of the crystal. The diffraction extends to at least 2.5 A.  相似文献   

16.
Crystals of ferrocytochrome c2 from a non-sulphur purple photosynthetic bacterium, Rhodopseudomonas viridis, have been grown from ammonium sulphate solution at pH 8.5 by the sitting-drop vapour-diffusion procedure. The crystals belong to the trigonal system, space group P3(1)21 (or its enantiomorph P3(2)21) with unit-cell dimensions of a = b = 75.8 A and c = 40.1 A, and diffract to at least 2.0 A resolution. Assuming that an asymmetric unit contains one protein molecule (approx. 12,300 Mr), the solvent content of the crystal is approximately 54.5% (v/v).  相似文献   

17.
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   

18.
Crystals of the high-potential iron-sulfur protein from Ectothiorhodospira halophila strain BN 9626 have been grown from 3.4 to 3.5 M ammonium sulfate solutions at pH 7.5. The crystals belong to the space group P21 with unit cell dimensions of a = 60.00 A, b = 31.94 A, c = 40.27 A, and beta = 100.5 degrees. There are 2 molecules/asymmetric unit. The crystals diffract to at least 1.8 A, are stable in the x-ray beam, and are suitable for a high resolution x-ray crystallographic analysis.  相似文献   

19.
Crystals have been obtained of the DNA-binding domain of the yeast MAT alpha 2 repressor bound to a 21 base-pair DNA site. The crystals are grown from polyethylene glycol and CaCl2 and form in space group P2(1) with a = 60.1 A, b = 39.4 A, c = 68.7 A and beta = 98 degrees. They diffract to 2.9 A resolution and contain one protein-DNA complex in the crystallographic asymmetric unit.  相似文献   

20.
Single crystals of hydrogenase from Desulfovibrio vulgaris Miyazaki F   总被引:2,自引:0,他引:2  
The hydrogenase solubilized from the particulate fraction from Desulfovibrio vulgaris Miyazaki F (IAM 12604) has been crystallized. Although the solubilized hydrogenase purified by the previous method (Yagi, T., Kimura, K., Daidoji, H., Sakai, F., Tamura, S., and Inokuchi, H. (1976) J. Biochem. (Tokyo) 79,661-671) revealed a single band upon disc electrophoresis, it could not be crystallized. The apparently homogeneous hydrogenase has been separated into three components of similar molecular weights by high performance liquid chromatography on DEAE-Toyopearl. Each hydrogenase component was successfully crystallized by means of the vapor diffusion method with polyethylene glycol or 2-methyl-2,4-pentanediol as a precipitating agent. Seeding procedure is necessary to grow an x-ray grade crystal. Preliminary x-ray experiments reveal that crystals grown from one component are in space group of P2(1)2(1)2(1) with a = 102.1(1), b = 126.8 (3), and c = 66.9(1) A. The unit cell volume of 8.66 X 10(5) A3 suggests that it contains one molecule/asymmetric unit (Vm = 2.43). The crystals grown from another component are in the same space group with a = 99.6(1), b = 126.8(3), c = 66.9(1) A, and the unit cell volume is 8.45 X 10(5) A3 (Vm = 2.37). The crystals diffract more than 2.5 A and are suitable for complete crystal analysis. Up to 4 A resolution native data have been collected on a diffractometer.  相似文献   

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