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1.
A molecular fragment comprising the first two domains of the human vascular cell adhesion molecule-l (VCAM-l) has been crystallized by the vapor diffusion method. Two crystal forms have been examined by X-ray analysis: One crystal form belongs to the space group C2 with two molecules in the asymmetric unit and cell parameters: a = 122.1 Å, b = 48.9 Å, c = 73.4 Å, and β = 117.4°. The other crystal form belongs to the space group P21 with one molecule in the asymmetric unit and cell parameters: a = 40.4 Å, b = 45.7 Å, c = 54.7 Å, and β = 100.5°. Diffraction data up to 1.9 Å resolution have been collected for the C2 crystal form. © 1994 Wiley-Liss, Inc.  相似文献   

2.
Crystals of plastocyanins from pea and corn leaves have been obtained. Both are suitable for X-ray structure analysis with a resolution up to 1.8 Å. The crystal form of plastocyanin from pea leaves belongs to the space group P212121 with unit cell dimensions: a = 49.0 A?, b = 53.3 A?, c = 82.6 A?. The assumed number of protein molecules per asymmetric unit of the unit cell is two. Crystals of the oxidized (Cu2+) and reduced (Cu+) forms are isomorphic. No essential differences in spot intensities for the main zone with a resolution of 3 Å were revealed. The crystal form of plastocyanin from corn leaves belongs to the space group P1 with unit cell parameters: a = 24.8 A?, b = 30.0 A?, c = 58.5 A? and α = 96° 10′, β = 87°08′, γ = 78°40′. The assumed number of protein molecules per asymmetric unit is two.  相似文献   

3.
The membrane-bound GPI-anchored zinc metalloproteinase leishmanolysin purified from Leishmania major promastigotes has been crystallized in its mature form. Two crystal forms of leishmanolysin have been grown by the vapor diffusion method using 2-methyl-2,4-pentanediol as the precipitant. Macroseeding techniques were employed to produce large single crystals. Protein microhet-erogeneity in molecular size and charge was incorporated into both crystal forms. The tetragonal crystal form belongs to the space group P41212 or the enantiomorph P43212, has unit cell parameters of a = b = 63.6 Å, c = 251.4 Å, and contains one molecule per asymmetric unit. The second crystal form is monoclinic, space group C2, with unit cell dimensions a = 107.2 Å, b = 90.6 Å, c = 70.6 Å, β = 110.6°, and also contains one molecule per asymmetric unit. Both crystal forms diffract X-rays beyond 2.6 Å resolution and are suitable for X-ray analysis. Native diffraction data sets have been collected and the structure determination of leishmanolysin using a combination of the isomorphous replacement and the molecular replacement methods is in progress. © 1995 Wiley-Liss, Inc.  相似文献   

4.
The selenium-containing phycocyanin from the selenium-rich algae (Spirulina platensis) has been crystallized in two crystal forms by the hanging-drop vapor diffusion techniques. A chromatographic procedure of gel filtration and anion exchange was used for purification. Form I crystal with space group P21 and cell parameters a =108.0 Å , b = 117.0 Å , c = 184.0 Å , β = 90.2° and 12(αβ ) units in the asymmetric unit was obtained by using (NH4)2SO4 as precipitant. These crystals diffract up to 2.8 Å . Form II crystal obtained by using PEG4000 as precipitant belongs to space group P63 with unit cell constants a = 155.0 Å , c = 40.3 Å , γ =120.0° and one(αβ ) unit in the asymmetric unit. The crystals diffract beyond 2.9 Å . The possible stacking forms of phycocyanin molecules in the first crystal form were discussed.  相似文献   

5.
The bifunctional flavoenzyme 5-hydroxyvaleryl-CoA dehydratase/ dehydrogenase has been crystallized from solutions containing ammonium sulfate (form I) or polyethylene glycol (form II) as precipitant. In both cases, the crystals grew in the monoclinic space group C2. The unit cell dimensions for form I crystals were determined as a = 162.8 Å, b = 71.8 Å, c = 83.5 Å, β = 109.1°. Corresponding values for form II crystals were a = 161.2 Å, b = 71.6 Å, c = 82.2 Å, β = 109.3°. In both cases most probably there are two monomers per asymmetric unit. The crystals diffract to about 2 Å resolution and are rather stable in the X-ray beam. © 1994 Wiley-Liss, Inc.  相似文献   

6.
Native toxic shock syndrom toxin 1 (TSST-1) purified from Staphylococcus aurius has been crystallized in four different forms. The highest resolution data (2.05 Å) was collected from orthorhombic crystals belonging to the space group C2221. The unit cell dimension are a = 108.7 Å, b = 177.5 Å, c = 97.6 Å. Rotation function analysis of this from indicates that there is trimer of toxin molecules in the asymmetric unit with a local 3-fold axis parallel to the crystallographic c axis. Crystals of a double mutant of TSST-1 have been grown which has a single molecule in the asymmetric unit and diffract to 1.9 Å. The space group is P21 with unit cell parameters of a = 44.4 Å, b = 34.0 Å, c = 55.2 Å, β = 93.0°. © 1993 Wiley-Liss, Inc.  相似文献   

7.
The tRNA modifying enzyme tRNA–guanine transglycosylase (Tgt) catalyzes the exchange of guanine in the first position of the anticodon with the queuine precursor 7-aminomethyl-7-deazaguanine. Tgt from Zymomonas mobilis has been purified by crystallization and further recrystallized to obtain single crystals suitable for x-ray diffraction studies. Crystals were grown by vapor diffusion/gel crystallization methods using PEG 8,000 as precipitant. Macroseeding techniques were employed to produce large single crystals. The crystals of Tgt belong to the monoclinic space group C2 with cell constants a = 92.1 Å, b = 65.1 Å, c = 71.9 Å, and β = 97.5°, and contain one molecule per asymmetric unit. A complete diffraction data set from one native crystal has been obtained at 1.85 Å resolution.  相似文献   

8.
The antitumor protein, neocarzinostatin, has been crystallized and examined by X-ray diffraction. Crystals of this globular protein are of space group P212121 with cell parameters a = 27.4Å, b = 33.9Åand c = 102.0Å. There is one molecule of approximately 27Ådiameter per asymmetric unit. Crystals soaked in a K2HgI4 solution give diffraction patterns significantly different from native crystal diffraction patterns.  相似文献   

9.
The endogenous Escherichia coli porin OmpF was crystallized as an accidental by‐product of our efforts to express, purify, and crystallize the E. coli integral membrane protein KdpD in the presence of foscholine‐12 (FC12). FC12 is widely used in membrane protein studies, but no crystal structure of a protein that was both purified and crystallized with this detergent has been reported in the Protein Data Bank. Crystallization screening for KdpD yielded two different crystals of contaminating protein OmpF. Here, we report two OmpF structures, the first membrane protein crystal structures for which extraction, purification, and crystallization were done exclusively with FC12. The first structure was refined in space group P21 with cell parameters a = 136.7 Å, b = 210.5 Å, c = 137 Å, and β = 100.5°, and the resolution of 3.8 Å. The second structure was solved at the resolution of 4.4 Å and was refined in the P321 space group, with unit cell parameters a = 215.5 Å, b = 215.5 Å, c = 137.5 Å, and γ = 120°. Both crystal forms show novel crystal packing, in which the building block is a tetrahedral arrangement of four trimers. Additionally, we discuss the use of FC12 for membrane protein crystallization and structure determination, as well as the problem of the OmpF contamination for membrane proteins overexpressed in E. coli.  相似文献   

10.
Formylmethanofuran:tetrahydromethanopterin formyltransferase from the hyperthermophilic methanogenic Archaeon Methanopyrus kandleri (growth temperature optimum 98°C) was crystallized by vapor diffusion methods. Crystal form M obtained with 2-methyl-2,4-pentanediol as precipitant displayed the space group P21 with unit cell parameters of a = 87.0 Å, b = 75.4 Å, c = 104.7 Å, and β = 113.9° and diffracted better than 2 Å resolution. Crystal form P grown from polyethylene glycol 8000 belonged to the space group I4122 and had unit cell parameters of 157.5 Å and 242.1 Å. Diffraction data to 1.73 Å were recorded. Crystal form S which was crystallized from (NH4)2SO4in the space group I4122 with unit cell parameters of 151.3 Å and 249.5 Å diffracted at least to 2.2 Å resolution. All crystal forms probably have four molecules per asymmetric unit and are suitable for X-ray structure analysis. © 1996 Wiley-Liss, Inc.  相似文献   

11.
The Fab fragment of the neutralizing monoclonal antibody SD6 elicited against foot-and-mouth disease virus (FMDV) C-SBcl and its complex with a peptide, corresponding to the major antigenic site of FMDV (VPl residues 136–150, YTASARGDLAHLTTT), have been crystallized using the hanging drop vapor diffusion techniques. For the isolated Fab, crystals diffracting to 2.5 Å resolution were obtained at room temperature using ammonium sulfate as precipitant. These crystals are monoclinic, space group C2, and unit cell parameters a = 109.53 Å, b = 89.12 Å, c = 64.04 Å, and β = 112.9° and contain one Fab molecule per asymmetric unit. Crystals from the complex diffract, at least, to 2.8 Å resolution and were obtained, at room temperature, using PEG as precipitant. These crystals are monoclinic, space group P2, and unit cell parameters a = 56.11 Å, b = 60.67 Å, c = 143.45 Å, and β = 95.4°, Density packing considerations indicate that there are two Fab molecules in the asymmetric unit. © 1994 John Wiley & Sons, Inc.  相似文献   

12.
Single crystals of the protein gelonin isolated from the seeds of Gelonium multiforum have been grown at room temperature by vapor diffusion method. The crystals are monclinic with a = 49.4 Å, b = 44.9 Å, c = 137.4 Å, and β = 98.3°. The space group is P21, with two molecules in the asymmetric unit which are related by a noncrystallographic 2-fold axis along ψ =13° and ? =88°. The crystals diffract X-rays to high resolution, making it possible to obtain an accurate structure of this single chain ribosome inactivating protein. © 1994 Wiley-Liss, Inc.  相似文献   

13.
Cartilage oligomeric matrix protein (COMP) is a pentameric glycoprotein of the thrombospondin family found in cartilage and tendon. Self-association of COMP is achieved through the formation of a five-stranded α-helical bundle that involves 64 N-terminal residues (from 20 to 83). The complex is further stabilized by the interchain disulfide bonds between cysteines 68 and 71. We have prepared, by expression in Escherichia coli, several peptides of different lengths from the N-terminal region of COMP and studied their amenability to crystallization. Crystals of the best quality were obtained with a peptide spanning COMP residues 28–72. This peptide forms disulfide linked pentamers with 87% of α-helical structure. Crystals were grown by the hanging drop vapor diffusion method, using polyethylene glycol 1500 as a precipitant. The crystals belong to space group P21 with unit cell dimensions a = 38.47 Å, b = 49.47 Å, c = 54.98 Å, β = 103.84° and contain one pentamer per asymmetric unit. They diffract strongly to at least 1.8 Å resolution.  相似文献   

14.
Spinach chloroplast coupling factor (CF1) was crystal-lized at 20°C from 0.05 M TRIS-PO4, containing 4 mM ATP, 15mM KCl, 1.0 mM EDTA and 1.80 M (NH4)2SO4, at pH 7.8. Some unit cell parameters were determined by electron microscopy and by X-ray diffraction. The cube shaped crystals have a tetragonal lattice, a = b = 135 Å, c = 280 Å with eight molecules per unit cell; possible space group P422 or P42212, hence half a molecule in the asymmetric unit. Crystals grown at pH 7.5 in the absence of ATP have an orthorhombic lattice, a = 125 Å, b = 145 Å, c = 169 Å (C2221), eight molecules per unit cell.  相似文献   

15.
Histidyl-tRNA synthetase (HisRS) has been purified from the extreme thermophile Thermus thermophilus. The protein has been crystallized separately with histidine and with its cognate tRNAHis. Both crystals have been obtained using the vapor diffusion method with ammonium sulphate as precipitant. The crystals of HisRS with histidine belong to the spacegroup P21212 with cell parameters a = 171.3 Å, b = 214.7 Å, c = 49.3 Å, α = β = γ = 90°. A complete data set to a resolution of 2.7Å with an Rmerge on intensities of 4.1% has been collected on a single frozen crystal. A partial data set collected on a crystal of HisRS in complex with tRNAHis shows that the crystals are tetragonal with cell parameters a = b = 232 Å, c = 559 Å, α = β = γ = 90° and diffract to about 4.5 Å resolution. © 1995 Wiley-Liss, Inc.  相似文献   

16.
Crystals of recombinant human Clara cell 10-kDa protein were grown both from ammonium sulfate and polyethylene glycol (PEG) solutions. Crystals grown from ammonium sulfate solution have been characterized by X-ray diffraction studies as monoclinic with the space group C2 and lattice constants a = 69.2 Å, b = 83.0 Å, c = 58.3 Å, and β = 99.7°. The monoclinic crystals diffract to beyond 2.5 Å. Some of the crystals grown from PEG were of a similar habit to those grown from ammonium sulfate, but others were triclinic with the space group P1 and cell constants a = 40.3 Å, b = 46.3 Å, c = 51.3 Å, α = 117.7°, β = 102.3°, and γ = 71.4°. These crystals diffract to beyond 3.2 Å. © 1994 Wiley-Liss, Inc.  相似文献   

17.
The 17 kDa protein from Betula verrucosa (White Birch) pollen, Bet v 1, is the clinically most important birch pollen allergen causing immediate Type I IgE-mediated allergy. The three-dimensional structure of Bet v 1 and its IgE-binding epitopes are at present not known. In addition, the biological function of Bet v 1 in birch pollen is not fully established. In this work, Bet v 1 has been expressed in Escherichia coli as a recombinant protein, purified and crystallized. The space group of recombinant Bet v 1 crystals is orthorhombic C2221 with unit cell parameters a = 32.13 Å, b = 74.22 Å, and c = 118.60 Å. There is one Bet v 1 molecule per asymmetric unit and the water content is 41%. Crystals diffract to 2.0 Å resolution and a complete native data set was collected from a single crystal using CuKα X-rays from a rotating anode. © 1996 Wiley-Liss, Inc.  相似文献   

18.
The thermostable amylopullulanase from Pyrococcus woesei was crystallized. Crystals, suitable for a crystallographic analysis up to a size of 0.6 mm in their longest dimension, have been obtained by the vapor diffusion method in a solution containing polyethyleneglycol 4000 (PEG 4000), isopropanol, and Tris/Cl? buffer pH 7.5. Crystals grown under these conditions form hexagonal rods and diffract to a maximum resolution of 3 Å. The crystals belong to the trigonal lattice type with the spacegroup P3121 or P3221, respectively, have the cell dimensions a = b = 96.8 Å, c = 196.2 Å, α = β = 90°,γ = 120°. The crystals have a theoretical packing density of 2.7 Å3/Da, assuming one molecule with a molecular weight of 88.8 kDa in the asymmetric unit. Furthermore the self-rotation analysis of the dataset revealed only crystallographic symmetries. The merged native data of two crystals resulted in a 88% complete dataset. © 1995 Wiley-Liss, Inc.  相似文献   

19.
Histone macroH2A has a novel hybrid structure consisting of a large nonhistone region and a region that closely resembles a full-length histone H2A. One key to understanding macroH2A function is determining the structure and function of its nonhistone region. The nonhistone region of one of the two known macroH2A subtypes was expressed in Escherichia coli and purified using affinity and molecular sieve chromatography. Crystals of the protein suitable for structural studies were grown from polyethylene glycol solutions by vapor equilibration techniques. The crystals belong to the hexagonal space group P64 (or its enantiomorph P62) with unit cell parameters: a = b = 106.2 Å, c = 125.9 Å, α = β = 90°, and γ = 120°. There are four molecules in the asymmetric unit. Self-rotation function studies revealed three twofold noncrystallographic rotation axes related approximately by 222 symmetry. These crystals have 47% solvent content and diffract to 3.8 Å resolution. © 1995 Wiley-Liss, Inc.  相似文献   

20.
Crystals of dogfish (Mustelus canis) C-reactive protein were obtained through vapor phase equilibration using the sitting drop rod technique with ammonium sulfate as the precipitating agent. The space group was determined to be P1 (triclinic lattice) with unit cell dimensions of a = 82.91, b = 92.25 and c = 103.40 Å; α = 83.36°, β = 89.76°, and γ = 81.30°. These crystals diffract to about 2.6 Å resolution and contain two hexamers in the asymmetric unit. © 1993 Wiley-Liss, Inc.  相似文献   

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