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1.
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   

2.
Letter: Packing of microfibrils in collagen   总被引:1,自引:0,他引:1  
X-ray diffraction data obtained from rat tail tendon can be indexed on a tetragonal unit cell with a = 2 × 38·47 A?, c = 4 × 670 A?, space group P41 or P43, in which all the intermicrofibril contacts are quasi-equivalent.  相似文献   

3.
Erysimum latent virus, a tymovirus, contains 180 protein subunits arranged in a T = 3 icosahedral surface lattice. A cubic crystal form (with space group P213 and a = 414 A?) and a monoclinic form (space group B2, a = 442 A?, b = 422 A?, c = 387 A?, γ = 95 °) have been observed. The asymmetric units of the two crystal forms contain one-third and one whole virus particle, respectively. Two possible packing arrangements of the virus particles in the monoclinic unit cell have been deduced from the low-angle diffraction patterns. X-ray diffraction data from the monoclinic crystals extend to at least 3·7 Å resolution.  相似文献   

4.
Conditions have been established for the crystallization of tyrosyl-transfer RNA synthetase from Bacillus stearothermophilus at room temperature. The crystals are extremely well-ordered, exhibiting diffraction spots out to at least 2.7 Å, and can be grown to a convenient size for X-ray crystallographic analysis. The crystals are trigonal with a space group P3121, the unit cell having dimensions of a = 64.4 A? and c = 238 A?; the crystallographic asymmetric unit is probably one subunit of the dimeric (2 × 45,000, mol. wt) enzyme. The enzyme crystals are extremely stable and exhibit good resistance to radiation damage. This amino-acyl-tRNA synthetase appears to be amenable to complete structure determination by X-ray crystallography.  相似文献   

5.
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   

6.
Crystals of lactate dehydrogenase from Bacillus stearothermophilus have been obtained in five different crystal morphologies belonging to at least two different space groups. Apo-lactate dehydrogenase can crystallize in space group P6122 or P6522 (a = 87 A?and c = 358 A?). A complex of lactate dehydrogenase with NADH and the effector fructose 1,6-diphosphate can crystallize in the same space group as the apoenzyme and in P6322 (a = 290 A?, c = 146 A?). Both forms are suitable for high resolution X-ray diffraction studies.  相似文献   

7.
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   

8.
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   

9.
Three new crystal forms of cow α-lactalbumin are described. A trigonal form in space group P3121 or P3221 has unit cell dimensions: a = b = 57.4 A?, c = 75.0 A?. A hexagonal form in space group P622 has unit cell dimensions: a = b = 94.0 A?, c = 67.1 A?. A second trigonal form grown in the presence of calcium ions belongs to space group P321 with unit cell dimensions: a = b = 93.7 A?, c = 66.9 A?. The significance of these new crystal forms to the structure determination of cow α-laetalbumin is discussed.  相似文献   

10.
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   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
Crystals of subtilopeptidase A have been studied by means of X-ray diffraction. They are orthorhombic, space group P212121 with a = 76 73 A?, b = 55.35 A?and c = 53.00 A?. There is one molecule per asymmetric unit and the solvent content is 42%. The crystals diffract very well and appear suitable for detailed study of the three-dimensional structure of the enzyme.  相似文献   

19.
Purification and crystallisation procedures are reported for azurin and cytochrome c′ from Alcaligenes denitrificans and Alcaligenes sp. NCIB 11015. The azurin crystals from A. denitrificans are suitable for high-resolution X-ray structure analysis. They are orthorhombic, space group C2221 (with marked tetragonal pseudo-symmetry), cell dimensions a = 75.0 A?, b = 74.1 A?, c = 99.5 A?, with two molecules per asymmetric unit. The cytochrome c′ crystals from both species are hexagonal, space group P6122 (or P6522), cell dimensions a = b = 54.7 A?, c ~ 185 A?, γ = 120 °, with one subunit (molecular weight 14,000) in the asymmetric unit.  相似文献   

20.
The orthorhombic crystals of l-asparaginase from Escherichia coli A-1-3 KY3598 were characterized by the X-ray diffraction method as belonging to the space group P21221 with unit cell dimensions a = 116.7 A?, b = 62.9 A? and c = 86.6 A?. The crystals contain one half of the tetrameric enzyme molecule per asymmetric unit, the smallest so far reported for this enzyme. Preliminary analysis of the Patterson map indicated that the molecule had at least pseudo 222 symmetry and established the position of the centers of the molecules in the unit cell.  相似文献   

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