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1.
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   

2.
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   

3.
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   

4.
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   

5.
The enzymically active, semisynthetic complex formed by residues 1 through 118 and residues 111 through 124 of bovine pancreatic ribonuclease has been crystallized at pH 5.7 from (NH4)2SO4CsCl solutions. The crystals belong to space group P3221, have unit cell dimensions a and b = 64.4 A?, c = 64.5 A?, and γ = 120° and are isomorphous with form M of ribonuclease A as well as forms W and R of ribonuclease S. They diffract well and may be expected to yield a structure defined to at least 3.0 Å resolution.  相似文献   

6.
The parvalbumin IIIf of the superfast swimbladder muscle of Opsanus tau has been crystallized by a vapor diffusion technique using (NH4)2SO4 as a precipitant agent. The crystals belong to space group P21, with a unit cell a = 27.31 A?, b = 58.75 A?, c = 30.83 A? and β = 98 ° 30′, and the asymmetric unit contains one molecule. These crystals are suitable for a high resolution crystallographic investigation.  相似文献   

7.
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   

8.
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   

9.
Crystals of the periplasmic ribose binding protein of Salmonella typhimurium have been subjected to X-ray analysis. The crystals grow as rectangular parallelopipeds with the symmetry of space group P21. Unit cell dimensions are a = 64·4 A?, b = 60·6 A?, c = 62·8 A?, and β = 91·25 °. There are two molecules of molecular weight 29,000 per asymmetric unit.  相似文献   

10.
Bovine platelet factor 4 has been crystallized by “vapor dilution” in space group P212121, a = 63.7 A?, b = 66.7 A?, c = 80.5 A?, with four molecules, each 9505 Mr, in the asymmetric unit. The crystals diffract X-rays to better than 2.8 Å resolution.  相似文献   

11.
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   

12.
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   

13.
Arc, a represser from Salmonella phage P22 has been crystallized from ammonium phosphate at pH 8.0. The crystals form in space group P212121 with a = 90.26 A?, b = 52.88 A? and c = 47.58 A?. The crystals diffract to 2.2 Å resolution.  相似文献   

14.
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   

15.
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   

16.
Uteroglobin is a steroid-binding protein of 15,800 molecular weight, composed of two chemically identical subunits which, in the oxidized form, are covalently linked by disulphide bridges. Large crystals have been grown from ammonium sulphate solutions by vapour diffusion as well as by equilibrium dialysis. The crystals are very stable under X-rays, diffract to at least 2.2 Å resolution and belong to space group P21. The unit cell, with dimensions a = 43.3 A?, b = 31.1 A?, c = 34.5 A?, and β = 90.7 °, contains two dimeric molecules. The crystals exhibit a prominent pseudo symmetry corresponding to space group P21212 which indicates that the two subunits should be structurally nearly identical.  相似文献   

17.
Crystals of triosephosphate isomerase (EC 5.3.1.1) from Trypanosoma brucei brucei have been grown. These crystals diffract to at least 2 Å, even after 60 hours of exposure to X-rays. The space group is P212121, with cell dimensions a = 112.4 A?, b = 97.8 A?, c = 48.0 A?. There is one dimer per asymmetric unit.  相似文献   

18.
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   

19.
Large single crystals of isocitrate dehydrogenase from Azotobacter vinelandii have been grown by vapor diffusion from ammonium sulfate and phosphate solutions. The crystals are tetragonal, space group P42212 with cell dimensions a = 122.1 A?, c = 163.9 a?. There are two molecules of 80,000 molecular weight per asymmetric unit. Native data to 5.5 Å resolution have been collected on a diffractometer. A rotation function using data between 10 Å and 6 Å resolution indicates three possible orientations of the non-crystallographic 2-fold axis relating the two molecules.  相似文献   

20.
The TET-repressor encoded by the transposon Tn10 has been crystallized along with the repressor-tetracycline complex. Both crystals belong to the space group P43212 (or P41212) with cell dimensions a = b = 74.3(1) A?, c = 94.2(2) A? and a = b = 73.3(1) A?, c = 94.6(2) A? for the free and complexed repressor, respectively. There is one molecule of molecular weight 23,000 per asymmetric unit, and the biologically active dimer therefore consists of two identically formed subunits which are related by a crystallographic 2-fold axis. This isomorphism of TET-repressor and its tetracycline complex suggests that only minor, subtle changes in structure trigger binding to or release of the operator. The crystals of the native protein permit X-ray data collection to 3.2 Å and those of the complexed repressor to 2.8 Å.  相似文献   

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