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1.
Desulforedoxin, a two-iron, two-chain protein from the bacterium Desulfovibrio gigas, has been crystallized. X-ray diffraction photos show symmetry consistent with space group P3121 or the enantiomorph P3221. Cell parameters are a = b = 42.28 A?, c = 72.46 A?.Crystals develop sufficiently well for an X-ray diffraction analysis of at least 2.0 Å resolution to be performed.  相似文献   

2.
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   

3.
Letter: crystallographic data fro lysoxyme from bacteriophage T4   总被引:3,自引:0,他引:3  
The lysozyme of bacteriophage T4 has been crystallized in a form suitable for X-ray diffraction analysis. The space group is P3121 or enantiomorph, and the cell dimensions are a = b = 61.1A?, c = 96.3A?.  相似文献   

4.
Pseudomonas aeruginosa cytochrome oxidase (nitrite reductase, cytochrome cd) has been crystallized in space group P21212 with cell dimensions a = 122.8 A?, b = 87.2 A?, c = 73.4 A?. Density measurements suggest that the asymmetric unit contains one 63,000 molecular weight subunit of the dimeric molecule. Crystal data agree well with electron microscopy of single molecules. The X-ray pattern extends beyond 2.5 Å resolution, and structure analysis is in progress.  相似文献   

5.
The major form of bovine erythrocyte carbonic anhydrase has been prepared by a new method in which the conventional chloroform-ethanol treatment is replaced by chromatography on DEAE-Sephadex. Single crystals, suitable for high resolution X-ray diffraction studies, have been obtained from enzyme prepared by this method. The space group is P6122. The unit cell contains 12 enzyme molecules and has the dimensions a = b = 68 A?, c = 244 A?.  相似文献   

6.
Renin isolated from the mouse submaxillary gland has been crystallized and is being subjected to X-ray diffraction analysis.The observed crystalline form has the following unit cell dimensions: a = 96.4 (1) A?, b = 104.4 (1) A?, c = 77.4 (1) A?, β = 101.2 (1) °, space group P21, Z = 8 (4 protein molecules in the asymmetric unit).Native data have been recorded at 5 Å resolution with an automatic diffractometer.  相似文献   

7.
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   

8.
Crystals of a relatively unspecific NAD(P)H dehydrogenase from human erythrocytes suitable for X-ray analysis have been grown. They belong to space group P41212 or its enantiomorph P43212 with unit cell dimensions: a = b = 79.3 A? and c = 38.1 A?. The asymmetric unit contains one molecule of Mr 18,000.  相似文献   

9.
The crystal structure of a regenerated form of (1→3)-α-d-glucan, obtained by solid state deacetylation of the triacetate derivative, has been determined by combined X-ray diffraction analysis and stereochemical model refinement. The structure crystallizes in an orthorhombic unit cell with parameters a = 16.46 A?, b = 9.55 A? and c (fibre repeat)=8.44 Å, and space group P212121. The chain conformation is nearly completely extended and is very close to a 2/1 helix, even though the dimer residue is the crystallographic repeat unit. An intramolecular O(2)  O(4)′ hydrogen bond stabilizes the conformation and extensive intermolecular hydrogen-bonding abilizes the packing. The resulting structure is sheet-like, with an alternating polarity of chain directions within the sheet. In its sheet-like character, extensive hydrogen-bonding, and insolubility in water, this polymorph of (1→3)-α-d-glucan resembles regenerated cellulose. The reliability of the structure analysis is indicated by the X-ray residual R=0.206.  相似文献   

10.
The dd-carboxypeptidase-endopeptidase of low penicillin sensitivity that is excreted by Streptomyces albus G has been crystallized from a polyethylene glycol (Mr 6000 to 7500) solution at pH 8.0. X-ray examination of the prismatic crystals shows that the space group is P21 with unit cell dimensions a = 51.1 A?, b = 49.7 A?, c = 38.7 A?, β = 100.6 ° and one molecule in the asymmetric unit. A crystal suspension made in 50 mm-Tris · HCl buffer (pH 8.0) supplemented with 5 mm-MgCl2 and 16% (wv) polyethylene glycol exhibits enzyme activity on the substrate Ac2-l-Lys-d-Ala-d-Ala.  相似文献   

11.
An orthorhombic form of beef liver catalase crystals has been examined by X-ray diffraction and electron microscopy. The space group is P212121 with a = 89A?, b = 140A?, and c = 231A?. Electron micrographs show the presence of broad channels arrayed in a hexagonal manner. The solvent content of these orthorhombic crystals is considerably less than that for previously reported trigonal crystals of beef liver catalase although the packing arrangement appears to be virtually the same, suggesting a possible symmetry transition upon dehydration.  相似文献   

12.
The esteroproteolytic enzyme, a serine protease from porcine pancreas, has been crystallized and characterized by X-ray diffraction. Two closely related crystal forms were observed. The unit cell dimensions of the first form are a = 59.2 A?, b = 96.4 A? and c = 47.4 A?, space group P21212 with one molecule (mol. wt 30,000) per asymmetric unit. The unit cell dimensions of the second form are a = 59.2 A?, b = 96.4 A? and c = 94.8 A?, space group P212121. Mercury derivatives of enzyme inhibitors were used to obtain multiple isomorphous heavy-atom substituents suitable for phase determination.  相似文献   

13.
The Mn superoxide dismutase from Escherichia coli has been obtained in three crystal forms: (I) from 68% saturated (NH4)2SO4, space group P222 or P2221, a = 47 A?, b = 103 A?, c = 47.5 A?, with one subunit per asymmetric unit; (II) from 50% polyethylene glycol 6000, space group C2221 (with approx. P41212 symmetry), a = 101 A?, b = 108 A?, c = 180 A?, with four subunits (2 molecules) per asymmetric unit; (III) from 52% polyethylene glycol with a different method of preparing the enzyme solution, space group P21212, a = 47 A?, b = 51 A?, c = 188 A?, with two subunits per asymmetric unit.The yeast mitochondrial Mn superoxide dismutase has yielded the same crystal form both from 30% 2-methyl-2,4-pentane diol and from 23% polyethylene glycol 6000: space group P212121, a = 63 A?, b = 115 A?, c = 125 A?, with four subunits (one molecule) per asymmetric unit.A full X-ray crystallographic study of at least one of these enzymes is planned.  相似文献   

14.
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   

15.
A pencillin-sensitive enzyme, the exocellular dd-carboxypeptidase-transpeptidase from Streptomyces R61, has been crystallized from polyethylene glycol (Mr = 6000 to 7500) solution at pH 7·6. X-ray examination of the orthorhombic crystals shows the space group is P212121, with unit cell dimensions a = 51·1 A?, b = 67·4 A?, and c = 102·9 A?. With four molecules of molecular weight 38,000, the A?3/dalton ratio for the cell is 2·33. The crystals are stable to irradiation for 75 hours and are suitable for structure analysis to at least 2·4 Å resolution. The radius of gyration of the molecule in solution at pH 6.8 is 20.8 Å.  相似文献   

16.
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   

17.
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   

18.
Poliovirus contains 60 copies each of four coat protein subunits arranged on a T = 1 icosahedral surface. Crystals of the Mahoney and the Sabin strains of the type I serotype of polio have been obtained. Crystals of the Mahoney strain belong to the orthorhombic space group P21212 with a = 324 A?, b = 359 A?, c = 381 A?, contain 12 virus particle in the asymmetric unit, and diffract to at least 2.5 Å resolution. The crystals are apparently identical to those characterized by Finch & Klug (1959). Collection of three-dimensional X-ray diffraction data to 2.9 Å resolution is in progress.  相似文献   

19.
Auromomycin and macromomycin from the organism Streptomyces macromomyceticus have been crystallized. The X-ray diffraction pattern of crystals of each molecule is consistent with space group P21212 with cell parameters a = 46.45 A?, b = 54.34 A? and c = 42.03 A? for auromomycin, and a = 46.45 A?, b = 54.52 A? and c = 41.54 A? for macromomycin. Diffraction analysis of auromomycin is in progress.  相似文献   

20.
Two crystal forms of lysozyme from the egg white of the embden goose (Anser anser) have been obtained, both of which are suitable for X-ray diffraction analysis. The monoclinic form has space group P21 with cell dimensions a = 38.3 A?, b = 65.7 A?, c = 45.2 a?, β = 116 ° and the triclinic form (space group P1) has cell dimensions of a = 39.9 A?, b = 42.2 A?, c = 57.9 A? and α = 98.8 °, β = 102.5 °, γ = 90.5 °.  相似文献   

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