首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Crystals of the Fab' fragment from the monoclonal anti-peptide antibody B1312 and of the Fab'-peptide antigen complex have been characterized. The monoclonal antibodies were raised against a synthetic homologue of the C-helix of myohemerythrin (residues 69-87 in myohemerythrin). The Fab'-peptide complex crystallizes in space group P6322 with unit cell dimensions a = b = 142.5 A, c = 101.5 A, alpha = beta = 90 degrees, gamma = 120 degrees, and Z = 1. The native Fab' crystallizes in space group P212121 with unit cell dimensions a = 98.0 A, b = 151.7 A, c = 80.8 A, alpha = beta = gamma = 90 degrees, and Z = 2. Both crystal forms diffract to beyond 2.6 A resolution. We also report the cDNA and predicted amino acid sequences for the variable regions of both the light and heavy chains of this anti-peptide antibody.  相似文献   

2.
The lumazine synthase-riboflavin synthase complex (heavy riboflavin synthase) of Bacillus subtilis consists of an icosahedral capsid of 60 beta-subunits containing a core of three alpha-subunits. The enzyme has been purified from the derepressed mutant H 94 of B. subtilis by a novel efficient procedure using column chromatography and preparative crystallization. Beta-Subunits were isolated after dissociation of the enzyme at pH 8.0. Ligand-driven renaturation of beta-subunits yields hollow icosahedral beta 60 capsids which could be crystallized in 1.55 M phosphate, pH 8.7, in three different modifications. A monoclinic modification belongs to space group C2 with unit cell dimensions of a = 235.5, b = 191.2, and c = 165.4 A and alpha = gamma = 90 degrees and beta = 134.4 degrees. The crystals contain two hollow beta 60 particles/unit cell and diffract to approximately 2.8-A resolution. A hexagonal modification has the space group P6(3)22 with unit cell dimensions of a = b = 157.2 and c = 300.8 A and alpha = beta = 90 degrees and gamma = 120 degrees. These cell parameters are similar to the dimensions of hexagonal crystals of native heavy riboflavin synthase (alpha 3 beta 60). A second hexagonal modification shows unit cell parameters of a = b = 156.3 and c = 622.6 A and alpha = beta = 90 degrees and gamma = 120 degrees. The space group of this modification could not be determined unambiguously.  相似文献   

3.
Crystals of a cardiotoxin from Taiwan cobra venom have been obtained by the vapor diffusion method using methyl pentanediol as precipitant. The crystals belong to the hexagonal space group P6(1)22 (or P6(5)22), with cell dimensions a = b = 47.5 A, c = 111.3 A, alpha = beta = 90 degrees and gamma = 120 degrees and diffract to a resolution of 2.2 A. There is one molecule per asymmetric unit and the solvent content is estimated to be 53%.  相似文献   

4.
Crystallographic studies of the catalytic subunit of cAMP-dependent protein kinase demonstrate that the presence of a 20 amino acid residue peptide inhibitor and MgATP during crystallization yields crystals with a different space group and, more significantly, makes an important difference in the quality of the resulting crystals. Under identical experimental conditions, the kinase crystallizes in a cubic space group P4(1)32 (a = b = c = 169.24 A), when no substrates or inhibitors are present, and in the hexagonal space group P6(1)22 (or P6(5)22) (a = b = 80.16 A, c = 288.07 A, alpha = beta = 90 degrees, gamma = 120 degrees) when a 20-amino acid residue peptide inhibitor and MgATP are present. Moreover, the hexagonal crystal diffracts to a resolution of 3.0 A, while the cubic crystals diffract to a resolution of 4.0 A.  相似文献   

5.
The pyridoxal phosphate-dependent enzyme dialkylglycine decarboxylase (E.C. 4.1.1.64) has been crystallized by vapor diffusion from a 15% polyethyleneglycol solution with sodium pyruvate as coprecipitant. The space group of the crystals is either P6(2)22 or the enantiomorph, P6(4)22, with one subunit of 46,500 Da per asymmetric unit. The unit cell has dimensions a = b = 152.7 A, c = 86.6 A, alpha = beta = 90 degrees, gamma = 120 degrees, and a solvent content of approximately 61%. diffraction extends to 2.3 A resolution.  相似文献   

6.
The complexes between the Fab fragments of two monoclonal anti-lysozyme antibodies, Fab10.6.6 (high affinity) and D44.2 (lower affinity), and their specific antigen, hen egg-white lysozyme, have been crystallized. The antibodies recognize an antigenic determinant including Arg68, but differ significantly in their association constants for the antigen. Two crystalline forms were obtained for the complex with FabF10.6.6, the higher affinity antibody. One of them is monoclinic, space group P21, with unit cell dimensions a = 145.6 A, b = 78.1 A, c = 63.1 A, beta = 89.05 degrees, consistent with the presence of two molecules of the complex in the asymmetric unit. These crystals diffract X-rays beyond 3 A making this form suitable for high-resolution X-ray diffraction studies. The second form crystallizes in the triclinic space group P1, with unit cell dimensions a = 134.0 A, b = 144.7 A, c = 98.6 A, alpha = 90.30 degrees, beta = 97.1 degrees, gamma = 90.20 degrees, consistent with the presence of 10 to 12 molecules of the complex in the unit cell. These crystals do not diffract X-rays beyond 5 A resolution. The antigen-antibody complex between FabD44.2, the lower affinity antibody, and hen egg-white lysozyme crystallizes in space group P2(1)2(1)2(1), with unit cell dimensions a = 99.7 A, b = 167.3 A, c = 84.7 A, consistent with the presence of two molecules of the complex in the asymmetric unit. These crystals diffract X-rays beyond 2.5 A resolution.  相似文献   

7.
beta-Hexosaminidase is a lysosomal hydrolase that is important in the metabolism of sphingoglycolipids. beta-Hexosaminidase B and beta-hexosaminidase A are the major isozymes in normal human tissue. beta-Hexosaminidase B is a homodimer of beta subunits, and beta-hexosaminidase A is a heterodimer composed of an alpha and a beta subunit. Crystals of beta-hexosaminidase B (M(r) 112,000) have been grown using the handling drop technique. They are elongated hexagonal prisms with maximum dimensions of 0.2 mm x 0.2 mm x 0.7 mm. The space group is P6(1)22 (or enantiomorph); the unit cell dimensions are a = b = 114.2 A, c = 402.2 A, alpha = beta = 90 degrees, gamma = 120 degrees. The molecular mass and cell dimensions suggest that there is one dimer per asymmetric unit. Crystals diffract to 3.2 A resolution.  相似文献   

8.
We have synthesized two thiourea derivatives of methyl anthranilate (1, 2) and their complexes with nickel (3) and platinum(II) (4). We have also prepared the complexes of nickel(II) with two benzoylthiourea derivatives (5, 6). The obtained compounds were characterized by elemental analysis, spectroscopic methods (FT-IR, UV-vis, NMR), mass spectrometry and thermal analysis. Compound 1, C(20)H(23)N(3)O(2)S, crystallizes in monoclinic space group P21/n, with Z=4, and unit cell parameters, a=8.8042(4) A, b=7.6608(3) A, c=28.834(2) A, alpha=gamma=90 degrees, beta=90.94(1) degrees. Compound 2, C(20)H(21)N(3)O(3)S, crystallizes in monoclinic space group P21/c, with Z=4, and unit cell parameters, a=7.7345(4) A, b=8.6715(4) A, c=29.113(2) A, alpha=gamma=90 degrees, beta=90.67(1) degrees. Compound 5, C(24)H(30)N(4)NiO(2)S(2), crystallizes in monoclinic space group P21/n, with Z=4, and unit cell parameters, a=10.4317(8) A, b=18.517(2) A, c=13.299(1) A, alpha=gamma=90 degrees, beta=104.53(1) degrees. Compound 6, C(25)H(28)Cl(2)N(4)NiO(4)S(2), crystallizes with a molecule of CH(2)Cl(2) in triclinic space group P-1, with Z=2, and unit cell parameters, a=10.362(1) A, b=11.849(2) A, c=12.536(2) A, alpha=90.04(2) degrees, beta=84.73(1) degrees, gamma=113.43(2) degrees. Compounds 1 and 2 show antifungal activity against the major pathogens responsible for important plant diseases (Botrytis cinerea, Colletotrichum fragariae, Fusarium oxysporum and Phoma betae). The antifungal activity is practically the same for morpholine and ethyl derivatives.  相似文献   

9.
Crystals suitable for X-ray analysis of porcine mitochondrial aspartate aminotransferase in the closed conformation were obtained after the apoenzyme was reconstituted with N-5'-phosphopyridoxyl-L-aspartate, an inhibitor in which the cofactor is covalently bound to the substrate. This results in a crystal form that has not been encountered previously in studies of aspartate aminotransferases. The crystals belong to the trigonal space group P3121 (or the enantiomeric P3221) with unit cell dimensions alpha = b = 202.0 A, c = 58.0 A, alpha = beta = 90 degrees, gamma = 120 degrees and contain one dimer in the asymmetric unit.  相似文献   

10.
Crystals of troponin C from turkey skeletal muscle suitable for high resolution X-ray studies have been grown from a Ca2+-containing solution. These crystals diffract to at least 2.5 A resolution, and have space group P3(1)21 or P3(2)21 and the following cell dimensions: a = b = 66.6 A, c = 61.0 A, alpha = beta = 90 degrees, gamma = 120 degrees.  相似文献   

11.
DOPA decarboxylase from pig kidney, an alpha 2 dimeric enzyme of Mr = 107,000, has been crystallized by the vapour diffusion method with ammonium sulphate as precipitant. The crystals belong to the space group P6(2) (or its enantiomer P6(4)) and have unit cell dimensions of a = b = 155.9 A, c = 87.7 A, alpha = beta = 90 degrees, gamma = 120 degrees. They diffract to 2.6 A resolution. There is one dimeric molecule per asymmetric unit. Rotation function studies have revealed the orientation of the non-crystallographic 2-fold axis of the dimer in the asymmetric unit.  相似文献   

12.
Sialoadhesin is a macrophage-restricted cell surface receptor, consisting of 17 immunoglobulin domains, which mediates cell adhesion via the recognition of specific sialylated glycoconjugates. A functional fragment of sialoadhesin, comprising the N-terminal immunoglobulin domain, has been expressed in Chinese hamster ovary cells as both native (SnD1) and selenomethionyl (Se-SnD1) stop protein. The successful production of 86% selenomethionine-incorporated protein represents a rare example of production of selenium-labeled protein in mammalian cells. SnD1 and Se-SnD1 have been crystallized in the absence of ligand, and SnD1 has also been crystallized in the presence of its ligand 2,3 sialyllactose. The ligand-free crystals of SnD1 and Se-SnD1 were isomorphous, of space group P3(1)21 or P3(2)21, with unit cell dimensions a = b 38.9 A,c = 152.6 A, alpha = beta = 90 degrees, gamma = 120 degrees, and diffracted to a maximum resolution of 2.6 A. Cocrystals containing 2,3 sialyllactose diffracted to 1.85 A at a synchrotron source and belong to space group P2(1)2(1)2(1), with unit cell dimensions a = 40.9 A, b = 97.6 A,c = 101.6 A, alpha = beta = gamma = 90 degrees.  相似文献   

13.
Crystals of the NC1 domain of human type IV collagen   总被引:1,自引:0,他引:1  
Crystals of the non-collagenous C-terminal region (NC1) of type IV collagen have been obtained from human placenta. These crystals diffract to 2.0 A, and belong to space group P22(1)2(1), with cell dimensions a = 81 A, b = 158 A, c = 138 A, alpha = beta = gamma = 90 degrees. The crystals contain one hexamer in the asymmetric unit; they are very stable with respect to X-rays.  相似文献   

14.
The enzymically active, semisynthetic, non-covalent complex formed by residues 1 through 118 and residues 111 through 124 of bovine pancreatic ribonuclease A crystallizes at pH 5.2 from (NH4)2SO4/CsCl solution with space group P3(2)21 and unit cell dimensions a and b = 67.7 A, c = 65.1 A and gamma = 120 degrees. The catalytically defective enzyme that results from the replacement of phenylalanine 120 by leucine crystallizes isomorphously with the parent structure (a and b = 67.2 A, c = 64.7 A, gamma = 120 degrees).  相似文献   

15.
The NodL specified O-acetyltransferase from the microbial symbiont Rhizobium leguminosarum has been over-expressed in Escherichia coli and purified using affinity-elution dye chromatography as the key step. The protein has been crystallized at 20 degrees C in 18% PEG 600, 0.1 M Tris/HCl buffer, pH 8.5, containing 1% dioxane, 0.25% octyl-beta-glucoside, and 5 mM coenzyme A using the hanging drop vapor diffusion method. Ambient temperature X-ray diffraction studies reveal the space group to be hexagonal (P6(3)22) with lattice constants a = b = 77.08 A, c = 160.6 A, and alpha = beta = 90 degrees, gamma = 120 degrees. Crystals that are flash-frozen to 120 K diffract beyond 2.7 A.  相似文献   

16.
In this work, we report the crystallization of ovocleidin-17, the major protein of the avian eggshell calcified layer and the preliminary X-ray characterization of this soluble protein which is implied into the CaCO(3) formation of the eggshell in avians. Crystals belong to one of the trigonal space group P3 with cell dimensions a= b= 59.53 A and c = 83.33 A, and alpha=beta= 90 degrees and gamma=120 degrees. Crystals diffract up to 3.0 A.  相似文献   

17.
Annexin IV (endonexin) has been purified from chicken liver and crystallized by the vapour diffusion method. Crystals which diffract to at least 2.2 A have been obtained. They belong to space group R3 and have unit cell dimensions of a = b = 99.4 A, c = 96.2 A, alpha = 90 degrees, beta = 90 degrees, gamma = 120 degrees. There is one molecule of 32,500 Da per asymmetric unit.  相似文献   

18.
Bluetongue virus serotype 10 (BTV-10) VP7, expressed by insect cells infected with the recombinant baculovirus, has been purified and crystallized. Two crystal forms suitable for X-ray analysis have been obtained. Type I crystals belong to space group P6(3)22 with a = b = 95.2 A, c = 181.0 A, alpha = beta = 90 degrees gamma = 120.0 degrees, and contain a single subunit in the crystallographic asymmetric unit. They diffract to dmin = 3.0 A. Type II crystals belong to space group P2(1) with a = 69.4 A, b = 97.1 A, c = 71.4 A, beta = 109.0 degrees, and contain a trimer in the crystallographic asymmetric unit. They diffract to dmin = 2.1 A. These results, together with solution studies, show that the molecule is a trimer.  相似文献   

19.
The interaction of copper (II), zinc(II) and cadmium(II) with Trimethoprim (2,4-diamino-5-(3',4',5'-trimethoxybenzyl) pyrimidine) has been studied. The crystal structures of [Zn(Trim)2Cl2] (2) and [Cd(Trim)Cl2(CH3OH)]n (4) are reported. Compound (2) exhibits a distorted tetrahedral environment around the metal center and crystallizes in the triclinic space group P1 with a=10.2397(6), b=10.4500(6), c=16.3336(16) A, alpha=96.141(8), beta=106.085(5), gamma=96.551(5) degrees and Z=2. In complex (4), the Cd(II) centers are bridged sequentially by two chlorine ions to form infinite chains and present a six-coordinated environment; the compound crystallizes in the monoclinic P2(1)/C space group with a=13.958(5), b=7.532(2), c=18.390(2) A, alpha=90, beta=97.32(5), gamma=90 degrees and Z=4. In both structures the Trimethoprim acts as a monodentate ligand through the pyrimidinic nitrogen N(1) atom. The characterization of the Cu(Trim)2(CH3O)(ClO4) complex through EPR and magnetic measurements suggests a binuclear or polinuclear nature, with bridging methoxo groups. The complexes were screened for their activity against several bacteria, showing activity similar to that of trimethoprim.  相似文献   

20.
Crystals of pig lens aldose reductase have been grown from polyethylene glycol solutions at pH 6.2 and analysed by X-ray diffraction. Two crystal forms were obtained. The first belongs to space group P1 with unit cell dimensions a = 81.3 A, b = 85.9 A, c = 56.6 A, alpha = 102.3 degrees, beta = 103.3 degrees, gamma = 79.0 degrees, with four molecules in the unit cell related by a 222 non-crystallographic symmetry. The second crystal form is hexagonal. The space group is P6(2)22 with a = b = 101 A, c = 257 A and two molecules in the asymmetric unit. Both forms are suitable for X-ray structure analysis to better than 3 A resolution.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号