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1.
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   

2.
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   

3.
The ImmE7 protein, which can bind specifically to the DNase colicin E7 and neutralize its bactericidal activity, has been purified and crystallized in two different crystal forms by vapor diffusion method. The orthorhombic crystals belong to space group I222 or I212121 and have unit cell dimensions a = 75.1 Å, b = 50.5 Å, and c = 45.4 Å. The second form is monoclinic space group P21 with ceil dimensions a = 29.3 Å, b = 102.7 Å, c = 53.0 Å and β = 91.5°. The orthorhombic crystals diffract to 1.8 Å resolution, and are suitable for high-resolution X-ray analysis. © 1995 Wiley-Liss, Inc.  相似文献   

4.
1,3,8-Trihydroxynaphthalene reductase was crystallized in the presence of NADPH and the inhibitor tricyclazole. The crystals are trigonal, space group P3121 or its enantiomorph P3221. Two crystal forms with slightly different cell dimensions were obtained. Form A has unit cell dimensions a = b = 142.6 Å, c = 70.1 Å and form B cell dimensions a = b = 142.6 Å, c = 72.9 Å. The diffraction pattern of the latter crystal form extends to 2.5 Å resolution.  相似文献   

5.
Two different heparin-binding fragments of human fibronectin have been crystallized in forms which are suitable for crystal structure analyses. The 30 kDa hep-2A fragment, consisting of type III domains 12–14, was crystallized from solutions containing ammonium sulfate or polyethylene glycol 6000. The crystals grown in ammonium sulfate solutions were orthorhombic with space group I222 or I212121 with a = 68.1 Å, b = 88.6 Å, and c = 144.9 Å. The crystals grown in polyethylene glycol solutions are hexagonal with space group P6122 or P6522 witha a = b = 66.7 Å and c = 245.7 Å. The 40 kDa hep-2B fragment, consisting of type III domains 12–15, was also crystallized from solutions containing ammonium sulfate with the addition of glycerol. Glycerol proved an effective agent for reducing the number of crystals in the crystallization experiments, and thus, increasing the size of the crystals in these experiments. This crystal form is nearly isomorphous to the orthorhombic form of the hep-2A fragment with space group I222 or I212121 and a = 67.5 Å, b = 87.0 Å, and c = 144.3 Å. All crystal forms diffract to at least 3.5 Å resolution and contain a single molecule in the asymmetric unit. © 1993 Wiley-Liss, Inc.  相似文献   

6.
Endoglucanase CelC from Clostridium thermocellum expressed in Escherichia coli has been crystallized in two different crystal forms by the hanging drop method. Crystals of form I were grown with polyethylene glycol as a precipitant. They are orthorhombic, space group P212121, with cell dimensions a =51.4 Å, b =84.3 Å, and c =87.5 Å. Crystals of form II, obtained in ammonium sulfate solutions, belong to the tetragonal space group P41212 (or P43212) with cell dimensions of a = b = 130.7 Å and c = 69.6 Å. Diffraction data to 2.8 Å resolution were observed for both crystal forms with a rotating anode generator. Preliminary oscillation images of the orthorhombic form I crystals using a synchrotron radiation source show diffraction to 2.2 Å resolution, indicating that these crystals are suitable for high resolution crystallographic analysis. © 1994 Wiley-Liss, Inc.  相似文献   

7.
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   

8.
A neutral lipase from the filamentous fungus Rhizopus delemar has been crystallized in both its proenzyme and mature forms. Although the latter crystallizes readily and produces a variety of crystal forms, only one was found to be suitable for X-ray studies. It is monoclinic (C2, a = 92.8 Å, b = 128.9 Å, c = 78.3 Å, β = 135.8) with two molecules in the asymmetric unit related by a noncrystallographic diad. The prolipase crystals are orthorhombic (P212121, with a = 79.8 Å, b = 115.2 Å, c = 73.0 Å) and also contain a pair of molecules in the asymmetric unit. Initial results of molecular replacement calculations using the refined coordinates of the related lipase from Rhizomucor miehei identified the correct orientations and positions of the protein molecules in the unit cells of crystals of both proenzyme and the mature form. © 1994 John Wiley & Sons, Inc.  相似文献   

9.
A nonglycosylated (N30QN78Q) form of the human tissue inhibitor of metalloproteinases, TIMP-1, has been prepared and crystallized in a form suitable for X-ray diffraction analysis. Small single crystals have been grown using sodium tartrate as a precipitant. The crystals are in space group P21, with cell dimensions a = 35.28, b = 53.95, c = 48.56, and β = 96.0°. There is a single molecule of TIMP-1 in the asymmetric unit. The crystals diffract to at least 2.3 Å resolution. Complete data have been collected to 2.9 Å and a search for heavymetal derivatives is in progress. © 1993 Wiley-Liss, Inc.  相似文献   

10.
Single crystals were grown from affinity-purified stinging nettle lectin and from its complex with the specific trisaccharide NNN″ -triacetylchitotriose by vapor diffusion at room temperature. The lectin crystallizes in space group P212121 with unit cell dimensions a = 54.3 (1) Å, b = 62.2 (1) Å, and c = 92.4 (2) Å, and diffracts to 3.0 Å resolution. The asymmetric unit contains three lectin monomers. The crystals of the lectin-trisaccharide complex have space group P212121 with cell constants a = 37.69 (4) Å, b = 48.97 (6) Å, and c = 57.32 (4) Å. These crystals diffract to at least 2.0 Å resolution and the asymmetric unit contains one lectin monomer. A three-dimensional X-ray structure determination is on its way. © 1993 Wiley-Liss, Inc.  相似文献   

11.
Crystals have been obtained of a ternary complex containing the yeast a1/α2 homeodomain heterodimer bound to a 21-base pair DNA site containing two 5′ overhanging bases at each end. The crystals are grown from cobaltic hexamine and form in space group P61 or P65 with a = b = 133 Å, c = 45.4 Å. Crystals that are flash-frozen at ?179°C diffract to 2.7 Å along the c-axis and to 2.4 Å in perpendicular directions. The crystals contain one protein–DNA complex in the crystallographic asymmetric unit. © 1995 Wiley-Liss, Inc.  相似文献   

12.
The X-prolyl dipeptidyl aminopeptidase PepX, a serine peptidase isolated originally from Lactococcus lactis subsp lactis NCDO 763, was cloned and overproduced in Escherichia coli. The enzyme was isolated in its active form in two purification steps. Crystals of PepX were grown by the hanging drop vapor diffusion method using polyethyleneglycol 4000 as precipitant at pH 5.0. The crystals are orthorhombic with cell dimensions a = 92.8 Å, b = 102.6 Å, and c = 101.6 Å, space group P21212, and probably contain one monomer of 87.5 kDa in the asymmetric unit. The crystals, very stable under X-rays, diffract to at least 2.2 Å and are suitable for high-resolution structural analysis. © 1995 Wiley-Liss, Inc.  相似文献   

13.
Methylenetetrahydrofolate([H4] folate) dehydrogenase (D) and methenyl[H4] folate cyclohydrolase (C) coexist as a bifunctional enzyme (DC) or as the amino-terminal domain of a trifunctional enzyme (DCS) where the third activity is 10-formyl[H4]lfolate synthetase (S). Two crystal forms of the DC domain of the human cytosolic DCS enzyme have been grown from polyethyleneglycol solution. The monoclinic P21 crystals diffract to 2.8 Å with a = 72.5 Å, b = 68.5 Å, c = 125.2 Å, and β = 91.8° but were found to be twinned. The orthorhombic P212121 crystals diffract to 2.5 Å with a = 67.7 Å, b = 135.9 Å, c = 61.6 Å, and contain two molecules per asymmetric unit. Proteins 26:479–480 © 1996 Wiley-Liss, Inc.  相似文献   

14.
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   

15.
J. P. Allen 《Proteins》1994,20(3):283-286
The reaction center from the nonsulfur purple bacteriumRhodobacter sphaeroideshas been crystallized in a new form. The crystals grew in the presence of polyethylene glycol 4000, the detergent β-octyl glucoside, and the amphiphiles heptane triol and benzamidine hydrochloride, using the sitting drop method. The space group of these crystals is tetragonal, P41(43)212, and the cell constants are a = b = 141.5 Å and c = 276.7 Å with probably 2 proteins per asymmetric unit. A native data set has been set collected to a resolution of 2.8 Å consisting of 56,332 unique reflections (50,731 with F > 2σ) with anRsym of 9.5%. Analysis of the diffraction data is underway using molecular and isomorphous replacement. © 1994 Wiley-Liss, Inc.  相似文献   

16.
The solid state conformations of cyclo[Gly–Proψ[CH2S]Gly–D –Phe–Pro] and cyclo[Gly–Proψ[CH2–(S)–SO]Gly–D –Phe–Pro] have been characterized by X-ray diffraction analysis. Crystals of the sulfide trihydrate are orthorhombic, P212121, with a = 10.156(3) Å, b = 11.704(3) Å, c = 21.913(4) Å, and Z = 4. Crystals of the sulfoxide are monoclinic, P21, with a = 10.662(1) Å, b = 8.552(3) Å, c = 12.947(2) Å, β = 94.28(2), and Z = 2. Unlike their all-amide parent, which adopts an all-trans backbone conformation and a type II β-turn encompassing Gly-Pro-Gly-D -Phe, both of these peptides contain a cis Gly1-Pro2 bond and form a novel turn structure, i.e., a type II′ β-turn consisting of Gly–D –Phe–Pro–Gly. The turn structure in each of these peptides is stabilized by an intramolecular H bond between the carbonyl oxygen of Gly1 and the amide proton of D -Phe4. In the cyclic sulfoxide, the sulfinyl group is not involved in H bonding despite its strong potential as a hydrogen-bond acceptor. The crystal structure made it possible to establish the absolute configuration of the sulfinyl group in this peptide. The two crystal structures also helped identify a type II′ β-turn in the DMSO-d6 solution conformers of these peptides. © 1993 John Wiley & Sons, Inc.  相似文献   

17.
X-ray quality crystals of class I deoxyribose-5-phosphate aldolase from Escherichia coli have been obtained for the unliganded enzyme and in complex with its substrate, 2-deoxyribose-5-phosphate. The enzyme catalyzes the reversible cleavage of 2-deoxyribose-5-phosphate to acetaldehyde and D-glyceraldehyde-3-phosphate. The unliganded and complex crystals are prismatic long rods and belong to the orthorhombic space group P212121 with cell dimensions a = 183.1 Å, b = 61.4 Å, c = 49.3 Å and a = 179.2 Å, b = 60.5, Å, c = 49.1 Å, respectively. Two molecules in the asymmetric unit are related by a noncrystallo-graphic 2-fold axis. The crystals are stable in the X-ray beam and diffract to at least 2.6 Å. A new method, reverse screening, designed to minimize protein utilization during the screening process was used to determine supersaturation and crystallization conditions. © 1995 Wiley-Liss, Inc.  相似文献   

18.
The catalytic domain of cellulase CelA, a family 8 glycohydrolase from C. thermocellum, has been crystallized in the orthorhombic space group P212121 with unit cell dimensions a = 50.12 Å, b = 63.52 Å, c = 104.97 Å. The diffraction pattern extends beyond 1.5 Å resolution. © 1996 Wiley-Liss, Inc.  相似文献   

19.
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   

20.
RepA1 protein is essential for replication of the RepFIC replicon of enterotoxin plasmid EntP307 and is thought to interact directly with the origin of replication. We have purified RepA1 from an over-producing expression system and have prepared single crystals using a macroseeding technique. The crystals belong to space group P212121 or P21212, with cell dimensions a = 61 Å, b = 67 Å, and c = 243 Å. They diffract X-rays to 3.3 Å resolution and probably contain two 40,000 molecular weight RepA1 molecules per asymmetric unit. © 1996 Wiley-Liss, Inc.  相似文献   

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