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1.
Large crystals of human transferrin have been grown from polyethylene glycol solutions. The crystals are orthorhombic, space group P212121, with a = 78 A?, b = 94 A? and c = 112 A?. Density measurements indicate that there are four transferrin molecules in the unit cell.  相似文献   

2.
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   

3.
Macromomycin (Mr 12,000) is the apoprotein of the antitumor drug auromomycin, which inhibits DNA synthesis by causing single-strand breaks in DNA. Two orthorhombic crystal forms of macromomycin have been observed. The platelike crystals of one form belong to space group P212121, with cell dimensions a = 48·92 A?, b = 54·71 A?, c = 103·31 A?, Z = 8. The crystals of the second form are needle-shaped, and belong to space group P21212, with cell dimensions a = 46·1 A?, b = 54·4 A?, c = 41·2 A?, Z = 4. At this point in time, the platelike crystals appear the most suitable for continued crystallographic studies.  相似文献   

4.
Large crystals of bovine thymus ubiquitin, a non-histone chromosomal protein, were grown from polyethylene glycol solutions. The crystals are orthorhombic, space group P212121, with a = 50·9 a?, b = 42·9 A? and c = 29·0 A?. The asymmetric unit contains one ubiquitin molecule.  相似文献   

5.
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   

6.
Large single crystals of ω-amino acid: pyruvate aminotransferase, were prepared by dialysis of the enzyme solution against 2.2 m-ammonium sulphate solution at pH 7.8. X-ray diffraction patterns show that the crystals belong to the orthorhombic space group I222 or I212121 with unit cell dimensions a = 124.1 A?, b = 137.9 A?, and c = 61.2 A?. The asymmetric unit consists of one monomer of molecular weight 43,000.  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.
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   

9.
Immunity protein, an inhibitor of the ribonuclease activity of the protein antibiotic colicin E3, crystallizes in the orthorhombic space group C222 with cell dimensions a = 78·7 A?, b = 54·1 A?, c = 36·1 A? and one molecule of Mr 9800 per asymmetric unit. The crystals are suitable for high resolution X-ray analysis.  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.
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   

12.
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   

13.
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   

14.
A cross-linked derivative of ribonuclease A, Nε,Nε′-(2,4-dinitrophenylene-1,5)-(lysine7-lysine41)-RNase A, has been crystallized by dialysis against 30% (vv) ethanol/water mixtures buffered at high pH. Single crystals belong to the orthorhombic space group P212121, a = 37.2 A?, b = 41.2 A?, b = 41.2 A?, with one molecule in the Crystallographic asymmetric unit.  相似文献   

15.
Octahedral shaped crystals of about 1 mm were grown from catalase of Micrococcus luteus. The space group was determined as P422121 with a = b = 106.6 A? and c = 106.3 A?. In contrast to mammalian catalase, the bacterial catalase contains only one subunit per asymmetric unit. This proves that the four subunits of bacterial catalase are identical.  相似文献   

16.
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   

17.
Uteroglobin, which is a progesterone-binding protein of the rabbit uterine secretion, has been crystallized and subjected to X-ray diffraction analysis. Two crystalline forms have been observed: a triclinic one (P1, Z = 2, a = 36.36 (4) A?, b = 37.40 (4) A?, c = 53.28 (4) A?, α = 104.6 (1) °, β = 97.0 (1) °, γ = 111.3(1) °); and an orthorhombic one for which the cell is C-centred with a = 50.86 (5)A?, b = 52.22 (5)A?, c = 47.28 (5) A?, space group C2221, Z = 4. Three isomorphous derivatives have been obtained. The crystals appear suitable for detailed study of the three-dimensional structure of the protein.  相似文献   

18.
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   

19.
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   

20.
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   

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