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1.
Bacillus subtilis ferrochelatase (EC 4.99.1.1), the final enzyme in protoheme IX biosynthesis, was produced with an inducible T7 RNA polymerase expression system in Escherichia coli and purified from the soluble cell fraction. It was crystallized from polyethylene glycol solution using the microseeding technique. The crystals diffract to a minimum Bragg spacing of 2.1 Å. The space group is P42 with unit cell dimensions a = b = 50.2 Å, c = 120.1 Å. © 1995 Wiley-Liss, Inc.  相似文献   

2.
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   

3.
Cartilage extracellular matrix link protein, having molecular mass of approximately 40 kDa, is a metalloprotein that binds divalent cations and is only soluble in low ionic strength solutions. The link protein was purified from bovine trachea and has been crystallized by a vapor diffusion method using PEG 3350 as precipitant. The crystal symmetry is P1, and the unit cell dimensions are a = 43.55, b = 53.11, c = 60.10 Å, α = 90.44, β = 106.21, γ = 101.51°. The VM of 1.8 Å3/Da is consistent with the presence of two molecules of the link protein in the asymmetric unit. The crystals diffract X-rays from a synchrotron source to 1.7 Å resolution. © 1995 Wiley-Liss, Inc.  相似文献   

4.
Chitinase from barley seeds has been crystallized at room temperature using polyethylene glycol as precipitant. The crystal is monoclinic, belonging to the space group P21, with unit cell parameters of a = 69.43 Å, b = 44.55 Å, c = 81.41 Å, and β = 111.95 Å. The asymmetric unit seems to contain two molecules of chitinase with a corresponding crystal volume per protein mass (VM) of 2.25 Å3/Da and a solvent content of 45% by volume. The crystal diffracts to at least 2.0 Å with X-rays from a rotating anode source and is very stable in the X-ray beam. X-ray data have been collected to better than 2.2 Å Bragg spacing from a native crystal. © 1993 Wiley-Liss, Inc.  相似文献   

5.
CytB, a membrane pore-forming toxin from Bacillus thuringiensis subspecies kyushuensis, is specifically toxic to dipteran insect larvae but broadly cytolytic in vitro. It has been purified in the protoxin form from a recombinant Escherichia coli source and crystals have been obtained which diffract X-rays to at least 2.6 Å resolution. The tendency for CytB to aggregate in solution was overcome by including 50 mM of urea or 8 mM of ethanolamine during crystallization. Mutants designed to add or subtract single cysteine residues for the purpose of heavy atom derivative preparation were similarly purified and crystallized. The crystals are hexagonal bipyramids. They belong to space group P6122 (or P6522) with lattice constants a = b = 67.34 Å, c = 170.96 Å, and contain one molecule of the CytB protoxin (MW 29235) per asymmetric unit and 27% solvent by volume. © 1995 Wiley-Liss, Inc.  相似文献   

6.
Phospholipid transfer protein from maize seedlings has been crystallized using trisodium citrate as precipitant. The crystal belongs to the orthorhombic space group P212121 with unit cell dimensions of a = 24.46 Å, b = 49.97 Å, and c = 69.99 Å. The presence of one molecule in the asymmetric unit gives a crystal volume per protein mass (Vm) of 2.36 Å 3/Da and a solvent content of 48% by volume. The X-ray diffraction pattern extends at least to 1.6 Å Bragg spacing when exposed to both CuKα and synchrotron X-rays. A set of X-ray data to approximately 1.9 Å Bragg spacing has been collected from a native crystal. © 1994 Wiley-Liss, Inc.  相似文献   

7.
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   

8.
The Fv fragment of a monoclonal antibody, 7E2 (IgG1, κ, murine), which is directed against the integral membrane protein cytochrome c oxidase (EC 1.9.3.1) from Paracoccus denitrificans, was cloned and produced in Escherichia coli. Crystals suitable for highresolution X-ray analysis were obtained by microdialysis under low salt conditions. The crystals belong to the orthorhombic space group P212121 with unit cell dimensions of a = 51.51 Å, b = 56.15 Å, c = 99.86 Å (1 Å = 0.1 nm) and contain one F v fragment per asymmetric unit. Using synchrotron radiation diffraction data were collected up to 1.28 Å resolution. This high resolution is very unusual for a heterodimeric protein. The crystals should open the way for refining not only the atomic positions, but also for obtaining information about internal dynamics. © 1995 Wiley-Liss, Inc.  相似文献   

9.
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   

10.
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   

11.
The tetrameric KM+ lectin from the seeds of Artocarpus integrifolia has, when compared to other plant lectins, the singular property of directly inducing neutrophil migration into the peritoneal cavity or into the air pouch of rats. This protein crystals have been grown and they belong to the orthorhombic system with space group C2221. The unit cell parameters are a = 54.4 Å, b = 127.9 Å and c = 99.8 Å. A native diffraction dataset to 2.8 Å was collected and an analysis of the self-rotation function has shown the presence of only one independent non-crystallographic 2-fold axis orthogonal to the crystal b-axis, compatible with a dimer in the asymmetric unit. Proteins 27:157–159 © 1997 Wiley-Liss, Inc.  相似文献   

12.
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   

13.
Ribonuclease H from an extreme thermophile, Thermus thermophilus HB8, has been crystallized from solutions at low ionic strength. The crystals belong to the hexagonal space group P6 122 (or P6 522), with unit cell parameters a = b = 44.7 Å, c = 314.7 Å. They contain one 18,000 Mr molecule per asymmetric unit and diffract to 2.8 Å resolution. © 1993 Wiley-Liss, Inc.  相似文献   

14.
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   

15.
Peptidyl-tRNA hydrolase from Escherichia coli, a monomer of 21 kDa, was overexpressed from its cloned gene pth and crystallized by using polyethylene glycol as precipitant. The crystals are orthorhombic and have unit cell parameters a = 47.24 Å, b = 63.59 Å, and c = 62.57 Å. They belong to space group P212121 and diffract to better than 1.2 Å resolution. The structure is being solved by multiple isomorphous replacement. © 1997 Wiley-Liss Inc.  相似文献   

16.
A Bacillus thuringiensis respiratory mutant (AB1 strain) that shows premature sporulation and insecticidal crystal protein (ICP) production was isolated. The mutant strain harbours the cryIC and cryID insecticidal genes and could be important for the production of ICP highly toxic to Spodoptera sp. The mutant was selected by its increased capacity to oxidize. N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD). In this strain, cytochrome aa 3 expression is not repressed during the sporulation phase, in contrast with the wild-type strain. The growth, spore production, dissolved O2, O2 consumption, CO2 evolution rate and ICP production were recorded as a function of time. The AB1 mutant strain has a similar growth yield to the wild-type strain, but begins sporulation at least 4 h earlier. The AB1 strain consumes 74.5% more O2 than the wild-type strain, during the fermentation process. The mutation on strain AB1 has an important positive effect on ICP production. This procedure shows that ICP production could be increased during fermentation by increasing the respiration capacity of Bacillus thuringiensis. Correspondence to: A. Bravo  相似文献   

17.
The cry8C-type gene designated cry8Ca2, which was cloned and sequenced from a Bacillus thuringiensis isolate HBF-1 in China, consisted of an open reading frame of 3483 bp encoding a protein of 1160 amino-acid residues. Sequence analysis showed that the Cry8Ca2 protoxin of 130.5 kDa had 99.9% sequence homology with the previously reported Cry8Ca1 protein, with one mismatch between the two amino-acid sequences. When the Cry8Ca2 toxin was expressed in a crystal-negative strain of B. thuringiensis (HD-73), elliptical crystals were produced. Cell extracts from this recombinant strain showed insecticidal activity against Anomala corpulenta larva. Mutant cry8Ca2 genes, produced by polymerase chain reaction amplification with Taq DNA polymerase, were used to develop recombinant B. thuringiensis strains. Mutants producing higher levels of insecticidal activity were identified by bioassay. Thirty-five mutants forming crystals were characterized, and two of them showed significantly increased insecticidal activity against A. corpulenta larva. The 50% lethality concentrations (LC50) of the two mutants were 0.2334 × 108 and 0.2591 × 108 colony-forming units g−1, considerably lower than the LC50 of the wild-type strain HBF-1 (0.9583 × 108 CFU g−1) and that of B. thuringiensis serovar japonensis strain Buibui (1.0752 × 108 CFU g−1).  相似文献   

18.
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   

19.
The antitumour protein from the α-endotoxin of Bacillus thuringiensis var. thuringiensis has been purified, crystallized and partially characterized. The same protein also shows the insecticidal activity. According to amino acid analysis it is an acidic protein with a molecular weight of approx. 13 000.  相似文献   

20.
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   

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