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1.
Crystals of mitogenic lectin from pea seeds (Pisum sativum) have been grown. The crystals are in space group P212121 with unit cell dimensions: a = 51.0 ± 0.2 A?, b = 617 ± 0.2 A?, c = 137.6 ± 0.5 A?. The asymmetric unit has one protein molecule.  相似文献   

2.
A new crystal form of a mitogenic lectin from pea seeds (Pisum sativum) has been obtained which is suitable for high resolution structural work. The crystals are orthorhombic, space group P212121, with unit cell dimensions: a = 64.2Å, b = 72. 7Å, c = 108. 3Å. The asymmetric unit contains one protein molecule.  相似文献   

3.
The lectin from the seeds of Abrus precatorius has been crystallized and the crystals subjected to study by X-ray diffraction and electron microscopy. Three closely related crystal forms were obtained, of orthorhombic space group P212121 with a = 138 A?, b = 142 A?, and c = 173 A?, of tetragonal space group P41212 with a = b = 136 A?, c = 176 A?, and a twinned intermediate of the first two. From electron microscopy and two-dimensional spatial filtering of electron micrographs of the crystals, the molecule appears to consist of four similar domains grouped in a roughly planar diamond-shaped arrangement having a local intramolecular dyad axis. The average diameter of the Abrus lectin molecule is 50 to 60 Å and the individual domains appear to have a diameter of about 25 Å.  相似文献   

4.
Single crystals of an l-arabinose-binding protein from Escherichia coli B/r suitable for a high-resolution structural analysis have been obtained. An X-ray examination of the orthorhombic crystals shows the space group is P212121, with unit cell dimensions: a = 55.3 A?, b = 71.4 A? and c = 77.5 A?. The asymmetric unit contains one protein molecule with a molecular weight of 38,000.  相似文献   

5.
Crystals of plastocyanins from pea and corn leaves have been obtained. Both are suitable for X-ray structure analysis with a resolution up to 1.8 Å. The crystal form of plastocyanin from pea leaves belongs to the space group P212121 with unit cell dimensions: a = 49.0 A?, b = 53.3 A?, c = 82.6 A?. The assumed number of protein molecules per asymmetric unit of the unit cell is two. Crystals of the oxidized (Cu2+) and reduced (Cu+) forms are isomorphic. No essential differences in spot intensities for the main zone with a resolution of 3 Å were revealed. The crystal form of plastocyanin from corn leaves belongs to the space group P1 with unit cell parameters: a = 24.8 A?, b = 30.0 A?, c = 58.5 A? and α = 96° 10′, β = 87°08′, γ = 78°40′. The assumed number of protein molecules per asymmetric unit is two.  相似文献   

6.
Single crystals of adenylosuccinate synthetase, an essential component of purine biosynthesis, extracted from rabbit skeletal muscle were prepared as suitable specimens for X-ray structure analysis. The crystal belongs to the space group P43212 or P41212 with unit cell dimensions a = b = 71.2 A?, c = 194.8 A?. The asymmetric unit contains one protein molecule of 54,000 molecular weight.  相似文献   

7.
Cytochrome c7, a low potential, three heme-containing protein (molecular weight 9800) was isolated from Desulfuromonas acetoxidans and crystallized from polyethylene glycol solutions. The crystals belong to the orthorhombic space group P212121, with unit-cell dimensions a = 44·10 A?, b = 37·55 A? and c = 45·08 A? and have one molecule of protein per asymmetric unit.  相似文献   

8.
Crystals of N- and C-terminal fragments of elongation factor G (EF-G) from Escherichia coli have been grown from the preparations obtained by limited tryptic hydrolysis. Molecular masses of these fragments are equal to about 49,000 and 25,000, respectively. In the form of an additive complex they appear to be a major part of the native spatial structure of EF-G (Alakhov et al., 1979). Crystals of N-terminal fragment belong to space group P41212 or P43212 with unit cell dimensions a = b = 76.6 A? and c = 191.6 A?. Crystals of C-terminal fragment belong to space group P4122 or P4322 with unit cell dimensions a = b = 77.1 A? and c = 75.0 A?. In both cases the assumed number of protein molecules per asymmetric part of the unit cell is one.  相似文献   

9.
Three crystal forms of rabbit muscle creatine kinase have been grown, one of which seems suited to a high resolution X-ray diffraction study. The first form is of monoclinic space group P21 with a = 54 A?, b = 114 A?, c = 145 A?, β = 91 ° and has as the asymmetric unit two molecules of total molecular weight 160, 000. The second form, grown in the presence of mercurials, is of space group A2 with a = 52 A?, b = 165 A?, c = 237 A?, β = 91 ° and also has two molecules in the asymmetric unit. The third crystal form, grown in the presence of a high concentration of cysteine, is of apparent space group P212121, but evidence indicates that the true space group may be P21221. The dimensions of the orthorhombic unit cell are a = 47 A?, b = 86 A?, c = 125 A?, and the asymmetric unit contains a single protein subunit. Assuming the latter space group, then the creatine kinase molecule possesses a twofold axis relating two identical subunits.  相似文献   

10.
A toxic protein from the venom of the scorpion Centruroides sculpturatus has been crystallized. The crystals are orthorhombic, with unit cell dimensions a = 52.2 A?, b = 42.0 A? and c = 28.5 A?, space group P212121. Density measurements indicate that there are four molecules of toxin in the unit cell.  相似文献   

11.
Crystallographic study of the anti-tumor protein ricin   总被引:2,自引:0,他引:2  
The anti-tumor protein ricin (also called RCAII) has been crystallized in a form suitable for X-ray diffraction analysis. The crystal symmetry is orthorhombic spacegroup P212121 with a = 72.9, b = 79.1, c = 114.7 A? and a single ricin molecule of molecular weight 65,000 per asymmetric unit. The crystals diffract well and are stable in the X-ray beam. At least one useful heavymetal derivative has been found as part of a high-resolution study.  相似文献   

12.
Tobacco ringspot virus belongs to the nepovirus group of the small spherical plant viruses. It has been suggested that the protein capsid, which displays icosahedral symmetry, consists of 240 protein subunits which are arranged on a T = 4 surface lattice. The virus crystallizes in orthorhombic space group P212121 (a = 388 A?, b = 396 A?, and c = 405 A?). The unit cell contains four virus particles while the crystallographic asymmetric unit consists of one complete virion. X-ray diffraction data from the crystals extend to at least 3.3 Å resolution.  相似文献   

13.
The “goose-type” lysozyme isolated from the egg-white of the black swan Cygnus atratus has been crystallized. The space group is P21 with one molecule of protein in the asymmetric unit. The cell parameters are a = 46.2 A?, b = 65.1 A?, c = 38.7 A?, β = 110 °. The crystals diffract to a resolution of 2.25 Å and a set of diffraction data for the native protein has been collected photographically.  相似文献   

14.
Crystals of lysozyme from Streptomyces erythraeus are orthorhombic, space group P212121 with unit cell dimensions: a = 50.01 A?, b = 61.98 A? and c = 67.85 A?; and one molecule, of molecular weight about 18,500, per asymmetric unit.  相似文献   

15.
A complete human κ-type Bence—Jones protein (Fin) has been isolated and crystallized. Immunochemical and physicochemical characterization of protein Fin indicates that it is of the κ-chain subgroup, κII, and that it consists of two non-covalently bound intact monomers having a molecular weight of ~23,000 Crystals of Bence—Jones protein Fin obtained from ammonium sulfate solutions have the orthorhombic space group P212121 with cell dimensions a = 132.0 A?, b = 93.3 A?, and c = 42.3 A?. The asymmetric unit consists of a dimer of molecular weight ~46,000.  相似文献   

16.
A “naturally occurring” human κI VL dimer, designated Wat, has been isolated and crystallized. Protein Wat consists of two non-covalently bound monomers, each having a molecular weight of ~ 11,500. The monomer subunit is composed of an entire variable region light chain (VL) domain closely homologous to that of the κI Bence Jones protein Roy (Hilschmann &; Craig, 1965) as evidenced from amino acid composition, tryptic peptide map, and sequence analysis. Immunochemical studies substantiated that protein Wat is of the κ chain subgroup κI and lacks the isotypic and allotypic antigenic determinants associated with the κ constant region light chain domain. Two types of crystals of VL dimer Wat were obtained from ammonium sulfate or polyethylene glycol solutions. The type I crystals have unit cell dimensions of a = b = 82.6 A?, c = 60.3 A?, and the space group is hexagonal P62 or P64. The asymmetric unit consists of one VL dimer; the fractional volume of unit cell occupied by solvent is 0.51. The unit cell dimensions of the type II crystals are a = b = 1,08.3 A?, c = 108.8 A?; the space group is hexagonal P6122 or P6522. Three variable domains constitute the asymmetric unit of the type II crystals; the fractional value of the solvent (0.52) is compatible with the value obtained for the type I crystals.  相似文献   

17.
Levansucrase, an exocellular enzyme, has been isolated from a high producer mutant, the BS5C4 constitutive strain, of Bacillus subtilis. Three crystalline forms have been obtained, all three belonging to the orthorhombic space group P212121. The most suitable form for a three-dimensional structure investigation has cell dimensions, a = 68 A?, b = 125 A?, c = 54 A?. There is one molecule in the asymmetric unit.  相似文献   

18.
Eukaryotic cells contain a protein which specifically inhibits DNAsae I. This inhibitor protein is closely related to muscle actin. As shown here the inhibitor purified from calf spleen consists of two polypeptides: one which closely resembles muscle actin and a second (15,000 to 20,000 in molecular weight) whose combination with actin has not been recognized before. Crystals of the complex were obtained in ammonium sulphate. They belong to the orthorhombic space group P212121, have unit cell dimensions of a = 187.4 A?, b = 72.33 A? and c = 38.19 A?, and have one molecule of the spleen actin associated with one molecule of the low molecular weight protein per asymmetric unit.  相似文献   

19.
The structural protein, δ-crystallin, has been purified and crystallized from adult turkey lens. The crystals are orthorhombic and normally belong to space group P21212 with unit cell dimensions a = 99.9(2) A?, b = 133.4(3) A? and c = 69.1(2) A?. This corresponds to two molecules of molecular weight approximately 200,000 per unit cell. A second crystal form has also been found in which b and c increase to 135.4(3) Å and 140.0(3) Å. respectively, indicating four molecules per unit cell.  相似文献   

20.
Cowpea chlorotic mottle virus belongs to the brome mosaic virus group of the small spherical plant viruses. It contains 180 protein subunits, which are arranged on a T = 3 icosahedral surface lattice. The virus crystallizes in orthorhombic space group P21212 (a = 394 A?, b = 382 A?, and c = 397 A?). The unit cell contains four virus particles, while the crystallographic asymmetric unit consists of one complete virion. X-ray diffraction data from the crystals extend to nearly 3.0 Å resolution.  相似文献   

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