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1.
Macrophage inflammatory protein 2 (MIP-2) has been crystallized by vapor diffusion of an 11 mg/ml protein solution in 100 mM-ammonium acetate against 30 to 40% polyethylene glycol (average molecular mass of 3350 Da). The crystals belong to space group P2(1)2(1)2(1) and have unit cell dimensions of a = 42.7 A, b = 59.3 A, and c = 100.3 A. The molecular mass of the protein and volume of the unit cell suggest that there are four monomers in the asymmetric unit. A data set to 2.3 A has been collected, and the self-rotation function identifies the presence of a non-crystallographic 2-fold axis.  相似文献   

2.
Bovine P2 Myelin Basic Protein Crystallizes in Three Different Forms   总被引:1,自引:0,他引:1  
P2 protein is a minor component of the myelin membrane. We have crystallized this protein for high-resolution crystallographic study. Three crystal morphologies are available. Two of them are from ammonium sulfate, and one is from polyethyleneglycol (PEG). The unit cell of the most suitable crystals from PEG 4000 has the dimensions a = 91.3 A, b = 99.8 A, c = 56.0 A; is of space group P2(1)2(1)2(1); and contains up to four molecules per asymmetric unit. The limit of resolution is 2.7 A.  相似文献   

3.
Lactotransferrin is an iron-binding protein. It has been purified from buffalo colostrum. The purified lactotransferrin has been crystallized in 10% ethanol solution. The crystals are orthorhombic and the space group is P2(1)2(1)2(1) with unit cell dimensions a = 161.70 A, b = 155.75 A, c = 113.48 A. The asymmetric unit contains three molecules of the protein with a solvent content of about 59%. The crystals were stable in the X-ray beam and diffract beyond 3.5 A resolution. The native data have been collected and the structure determination is in progress.  相似文献   

4.
The major extracellular protein of Penicillium cyclopium has been isolated from its culture media and purified by ammonium sulfate fractionation, gel, and ion-exchange chromatography. We show this secreted protein to be endopeptidase. The molecular weight is approximately 32,000, the pI is 5.0, and the pH optimum using a variety of protein and synthetic substrates is around 7.0. Inhibition studies show that the protease is not inhibited by pepstatin nor by p-chloromercuribenzoic acid, indicating, respectively, that it is not an aspartyl protease nor a thiol protease. Complete inhibition is observed, however, with phenylmethanesulfonyl fluoride. Three crystal forms suitable for high resolution x-ray diffraction studies have been obtained from this purified protease with reflections being observed to well beyond 3.0 A resolution. One form having a needle morphology is of the orthorhombic crystal class and has space group P2(1)2(1)2(1). The unit cell dimensions are a = 41.9 A, b = 43.2 A, and c = 111.5 A with 1 molecule of the protease occurring in the asymmetric unit. The second form grown at pH values less than 6.0 has a plate morphology, is of orthorhombic space group P2(1)2(1)2(1), and has unit cell dimensions a = 59.12 A, b = 62.33 A, and c = 70.62 A. The third form is polyhedral in habit, is also of space group P2(1)2(1)2(1), and appears when the pH of the mother liquor is greater than 7.0. The cell dimensions of this crystal form are a = 57.07 A, b = 58.82 A, c = 70.79 A, and again there is 1 molecule/asymmetric unit. Three-dimensional structural analysis by x-ray diffraction is now underway. All crystal forms are somewhat denser than the norm having mass to volume ratios of 1.58, 2.00, and 1.85 A3/dalton, respectively.  相似文献   

5.
Human apo-lactoferrin in both native and deglycosylated forms has been purified, and crystals obtained by dialysis against low ionic strength buffer solutions. The crystals of native apo-lactoferrin are orthorhombic, space group P2(1)2(1)2(1) with cell dimensions a = 222.0 A, b = 115.6 A, c = 77.8 A and have two protein molecules per asymmetric unit. Two crystal forms of deglycosylated apo-lactoferrin have been obtained. One is orthorhombic, space group P2(1)2(1)2(1), with cell dimensions a = 152.1 A, b = 94.6 A, c = 55.8 A. The second is tetragonal, space group I4, with cell dimensions a = b = 189.4 A, c = 55.1 A. Both of the latter have only one molecule per asymmetric unit, and are suitable for high-resolution X-ray structure analysis.  相似文献   

6.
Human plasminogen kringle 4 has been crystallized in two different crystal forms: monoclinic, a = 32.78(3), b = 49.17(2), c = 46.27(3) A, beta = 100.67 degrees, space group P2(1), four molecules/unit cell, two molecules/asymmetric unit; orthorhombic, a = 32.09(7), b = 49.14(6), c = 49.47(9) A, space group P2(1)2(1)2, four molecules/unit cell. Both crystal forms have a large protein fraction (66% for monoclinic and 62% for orthorhombic) and diffract x-rays to 2.0 A resolution. A self-rotation function has been calculated with monoclinic data indicating a non-crystallographic 2-fold rotation approximately parallel to a* (peak height of 14.3 x sigma). Cross-rotation function calculations are in progress utilizing the coordinates of the conserved structure of kringle 1 of prothrombin and plasminogen kringle 4.  相似文献   

7.
Crystals of the mouse major urinary protein (MUP) and rat alpha-2u globulin (AMG) have been grown from solutions of polyethylene glycol 3350 and CdCl2, respectively. The crystals differ both in their morphologies and space groups but have very similar unit cell sizes. AMG crystallized in P2(1) (a = 56.6 A, b = 103.8 A, c = 62.7 A, beta = 95.1 degrees) with four subunits/asymmetric unit, while MUP gave crystals in P4(1)2(1)2 or P4(3)2(1)2 (a = 57.3 A, c = 109.9 A) with one subunit/asymmetric unit. Both crystal forms diffract beyond 2.8 A resolution.  相似文献   

8.
Crystals of a recombinant ubiquitin carrier protein from Arabidopsis thaliana have been grown from solutions of ammonium sulfate. The crystals are orthorhombic, space group P2(1)2(1)2(1); the axes are a = 41.8(1) A, b = 44.9(1) A and c = 83.2(1) A. The crystals are quite stable to X-rays and diffract beyond 2.1 A resolution. There is one molecule in the asymmetric unit.  相似文献   

9.
Crystals of a 60-amino-acid C-terminal deletion mutant of the herpes simplex virus 1 single-stranded DNA binding protein, ICP8, have been grown by hanging drop vapor diffusion. The colorless crystals grow as thin plates to a maximum size of approximately 0.3 mm x 0.3 mm x 0.05 mm. The space group is P2(1)2(1)2(1) with unit cell constants a = 101.2 A, b = 145.8 A, and c = 162.9 A. There are one or two molecules of ICP8 per asymmetric unit.  相似文献   

10.
Crystals of an ATPase fragment of bovine clathrin uncoating ATPase   总被引:1,自引:0,他引:1  
A 44,000 Mr amino-terminal, clathrin-independent ATPase fragment of the bovine clathrin uncoating ATPase has been crystallized in a form suitable for X-ray diffraction studies. The crystals are orthorhombic, space group P2(1)2(1)2(1), a = 145.3 A, b = 65.0 A, c = 46.9 A, with one protein molecule per asymmetric unit (1 A = 0.1 nm).  相似文献   

11.
We have obtained single crystals of a phosphate-binding protein (Mr = 34,400) that serves as initial receptor in osmotic shock-sensitive active transport in Escherichia coli. The crystals, suitable for high resolution crystallographic analysis, belong to the space group P2(1)2(1)2(1). The unit cell has dimensions of a = 41.97, b = 64.66, and c = 124.6 A and contains four protein molecules. Including this phosphate-binding protein, there are now a total of six different binding protein structures currently under investigation in our laboratory, the others being those specific for L-arabinose, D-galactose, D-maltose, sulfate, or leucine/isoleucine/valine.  相似文献   

12.
The amino terminal half of human lactoferrin (LfN) produced from transfected baby hamster kidney cells has been crystallized in its iron-saturated and iron-free forms. The crystals of glycosylated LfN and deglycosylated LfN are monoclinic, space group C2, with cell dimensions a = 133.0 A, b = 58.3 A, c = 58.3 A, alpha = 90.0 degrees, beta = 114.7 degrees, gamma = 90.0 degrees, and one molecule per asymmetric unit. Crystals of apo LfN have also been prepared using deglycosylated protein. These crystals are tetragonal, space group P4(1)2(1)2 (or P4(3)2(1)2), with cell dimensions of a = b = 58.4 A and c = 217.2 A and one molecule per asymmetric unit. Both the iron-saturated and the iron-free crystals are suitable for high resolution X-ray analysis.  相似文献   

13.
Crystallization of the DNA-binding Escherichia coli protein FIS   总被引:2,自引:0,他引:2  
The specific DNA-binding protein FIS (factor for inversion stimulation), which stimulates site-specific DNA inversion by interaction with an enhancer sequence, was purified from an Escherichia coli strain overproducing the protein. FIS was crystallized at room temperature by microdialysis against 1.2 to 1.5 M-sodium/potassium phosphate containing 10 mM-Tris.HCl, 0.5 to 1 M-NaCl and 1 mM-NaN3 at pH 8.0 to 8.2. The crystals are stout prisms and suitable for X-ray diffraction study beyond 2.5 A resolution. They belong to the orthorhombic space group P2(1)2(1)2(1). The unit cell has dimensions a = 47.57(4) A, b = 51.13(4) A, c = 79.83(6) A and contains one FIS dimer in the asymmetric unit.  相似文献   

14.
B. subtilis dihydroorotase is an important enzyme in de novo pyrimidine biosynthesis pathway and encoded by pyrC gene in pyr operon. pyrC was amplified from B. subtilis genomic DNA and cloned into expression vector pET21-DEST. Dihydroorotase was expressed soluble form in E. coli and purified. The protein was crystallized and diffracted to 2.2 A. The crystal belongs to P2(1)2(1)2(1) space-group, with unit cell parameters a = 48.864 A, b = 84.99 A, c = 203.05 A. There are 2 molecules per asymmetry unit.  相似文献   

15.
Crystals of a sarcoplasmic Ca(2+)-binding protein from the protochordate amphioxus have been grown from solutions of ammonium sulfate. The crystals are orthorhombic, space group C222(1), with unit cell axes a = 59.6(1) A, b = 81.3(1) A and c = 82.4(1) A. There is one molecule in the asymmetric unit. The crystals diffract beyond 2.5 A and show less than 20% decline in diffraction intensities after a three day exposure to X-rays from a laboratory rotating anode source.  相似文献   

16.
Crystals of sarcoplasmic calcium-binding proteins from Nereis diversicolor have been grown from solutions of ammonium sulfate. The crystals are monoclinic, space group P2(1); the axes are a = 43.65 (1), b = 56.05 (1), c = 65.77 (1) A, and beta = 92.58 (2) degrees. The crystals are quite stable to x-rays and diffract beyond 2.5 A resolution. The asymmetric unit contains two protein molecules.  相似文献   

17.
The first odorant-binding protein isolated from mammalian nasal mucosa is a dimer of subunits of identical molecular weight (19,000) that specifically binds bell pepper odorants, "green" smelling compounds. The protein can be purified in milligram quantities from tissue extractions by sequential use of a silica based anion exchange column and Mono-P chromatofocussing column. In the presence of the binding compound 2-isobutyl-3-methoxypyrazine and of the organic solvent 2-methyl-2,4-pentanediol (17%, v/v), the protein crystallizes in the monoclinic space group P2(1), with unit cell constants a = 54.3 A, b = 66.7 A, c = 41.5 A, beta = 97.2 degrees. From consideration of the crystal packing densities compatible with its unit cell, it can be concluded that two subunits of 19,000 Mr each are present in the asymmetric unit. The diffraction pattern on still photographs of this crystal form of the protein extends to 2.5 A resolution and allows for a detailed crystallographic investigation.  相似文献   

18.
Crystals of bovine antithrombin III were obtained in the presence of metal ions with ammonium sulphate as precipitating agent. Crystals belong to space group P4(1)2(1)2 or P4(3)2(1)2 with cell parameters a = b = 91.4 A, c = 383.1 A; there are two molecules per asymmetric unit. Electrophoresis experiments and amino acid sequence analysis of the N-terminal part of redissolved crystals suggest that the protein molecules are cleaved at the active site.  相似文献   

19.
The purification of bovine lactoferrin, its crystallization at low ionic strength, and preliminary X-ray crystallographic data are reported. The crystals, which grow from a two-phase system, are radiation-stable and suitable for a medium-resolution X-ray analysis. They are orthorhombic, space group P2(1)2(1)2(1), with cell dimensions a = 138.4 A, b = 87.1 A, c = 73.6 A, and one protein molecule in the asymmetric unit.  相似文献   

20.
Crystals of type I cAMP-dependent protein kinase regulatory subunit have been grown from solutions of ammonium sulfate. The crystals are square bipyramids, space group P4(1)2(1)2 (P4(3)2(1)2), with a = b = 106.9 +/- 0.6 A and c = 212.4 +/- 1.0 A. There are two dimers of the regulatory subunit/crystallographic asymmetric unit. The crystals are stable for 3-4 days in the x-ray beam and diffract to at least 3.5-A resolution.  相似文献   

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