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1.
Miller BE 《Life sciences》1999,65(21):2215-2222
A total of 61 human brain specimens were analyzed with both ELISA and Western Blot using the ALZ50 monoclonal antibody. The brain specimens included: Alzheimer's Disease (AD, n=31), AD/Down's (n=2), Normal (n=14), Parkinson's Disease (n=7), Huntington's chorea (n=2), Wernicke-Korsakov's Encephalopathy (n=3), and Motor Neuron Disease (n=2). The non-AD cases (n=28) had no detectable A68 by ELISA, and showed no A68 bands by Western blot. The AD cases (n=33), all were positive for A68 by the ELISA, but only 31 of 33 had visible A68 band by Western blot. Additionally, a method for solubilization of A68 is reported.  相似文献   

2.
Purified malate dehydrogenase (MDH) of Streptomyces aureofaciens was crystallized either in the absence or in the presence of NADH or NADPH coenzymes by hanging-drop vapour-diffusion method. An X-ray study has shown, that MDH crystals belong to space group C222(1) with unit-cell parameters a = 53.2 A, b = 104.6 A, c = 520.0 A, alpha = beta = gamma = 90( degrees ), MDH-NADH crystals to space group C2 with unit-cell parameters a = 51.5 A, b = 51.5 A, c = 256 A, alpha = beta = gamma = 90( degrees ), and MDH-NADPH crystals to space group C222(1) with unit-cell parameters a = 72, A b = 72 A, c = 520 A, alpha = beta = gamma = 90( degrees ). The crystal of native MDH diffracted to 2.1 A resolution.  相似文献   

3.
Trypanothione reductase, a flavoprotein disulfide reductase specific to trypanosomatid parasites, has been crystallized by vapor diffusion of a protein solution (10 mg/ml) against 22% polyethylene glycol (average Mr 8000) containing 100 mM-ammonium sulfate. Crystals of a size suitable for structure determination by X-ray diffraction have been obtained by seeding protein solutions with smaller crystals. The space-group is P21 (a = 60.9 A, b = 161.8 A, c = 58.4 A, beta = 99.1 degrees). The molecular mass and volume of the unit cell suggest that there is a dimer of the enzyme in the asymmetric unit, and this is confirmed by self-rotation functions calculated using data to 4.5 A resolution. The crystals diffract to beyond 3 A resolution. Crystals of another P21 form (a = 91.3 A, b = 114.4 A, c = 92.0 A, beta = 141.3 degrees) are observed to grow under similar conditions.  相似文献   

4.
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   

5.
孔红 《广西植物》2012,32(5):579-582
采用常规压片法,对豆科黄芪属6种植物制备染色体标本进行核型分析。结果表明:体细胞中期染色体数目分别为:沙打旺、斜茎黄芪、达乌里黄芪2n=16,均为二倍体;草木樨状黄芪2n=32,为四倍体;紫云英、鹰嘴紫云英则呈现多数目性,紫云英染色体数变动范围为55~65,64条稍多,鹰嘴紫云英染色体数变动范围51~65,62条稍多,均为混倍体。核型公式分别为:沙打旺2n=2x=16=12m+4sm;斜茎黄芪2n=2x=16=10m+6sm;达乌里黄芪2n=2x=16=16m;草木樨状黄芪2n=4x=32=32m;紫云英2n=64=62m+2sm;鹰嘴紫云英2n=62=12M+50m(2SAT)。染色体核型呈现多样性。  相似文献   

6.
Three crystal forms of canine myeloperoxidase are described. An orthorhombic form in space group P2(1)2(1)2(1) has unit cell dimensions: a = 108.3 A (1 A = 0.1 nm) b = 205.9 A and c = 139.9 A. A trigonal form in space group P3(1)21 or P3(2)21 has unit cell dimensions: a = b = 138.9 A and c = 145.2 A. A monoclinic form in space group C2 has unit cell dimensions: a = 117.2 A, b = 96.9 A, c = 131.4 A and beta = 116.3 degrees. Unusual features in the diffraction patterns of the monoclinic form place restrictions on the molecular packing in the crystal. The proposed model for the molecular packing requires that the myeloperoxidase molecule consist of two identical or near-identical halves. In the intact molecule these halves may be related either by a crystallographic dyad axis or by an approximate dyad axis in which one subunit is translated relative to the other by 3.2 A along the symmetry axis. The trigonal crystal form appears most suitable for high-resolution X-ray structural analysis.  相似文献   

7.
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   

8.
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   

9.
Aurora A is critical for mitosis and is overexpressed in several neoplasms. Its overexpression transforms cultured cells, and both its overexpression and knockdown cause genomic instability. In transgenic mice, Aurora A haploinsufficiency, not overexpression, leads to increased malignant tumor formation. Aurora A thus appears to have both tumor-promoting and tumor-suppressor functions. Here, we report that Aurora A protein, measured by quantitative protein gel blotting, is differentially expressed in major glioma types in lineage-specific patterns. Aurora A protein levels in WHO grade II oligodendrogliomas (n = 16) and grade III anaplastic oligodendrogliomas (n = 16) are generally low, similar to control epilepsy cerebral tissue (n = 11). In contrast, pilocytic astrocytomas (n = 6) and ependymomas (n = 12) express high Aurora A levels. Among grade II to grade III astrocytomas (n = 7, n = 14, respectively) and grade IV glioblastomas (n = 31), Aurora A protein increases with increasing tumor grade. We also found that Aurora A expression is induced by hypoxia in cultured glioblastoma cells and is overexpressed in hypoxic regions of glioblastoma tumors. Retrospective Kaplan-Meier analysis revealed that both lower Aurora A protein measured by quantitative protein gel blot (n = 31) and Aurora A mRNA levels measured by real-time quantitative RT-PCR (n = 58) are significantly associated with poorer patient survival in glioblastoma. Furthermore, we report that the selective Aurora A inhibitor MLN8237 is potently cytotoxic to glioblastoma cells, and that MLN8237 cytotoxicty is potentiated by ionizing radiation. MLN8237 also appeared to induce senescence and differentiation of glioblastoma cells. Thus, in addition to being significantly associated with survival in glioblastoma, Aurora A is a potential new drug target for the treatment of glioblastoma and possibly other glial neoplasms.  相似文献   

10.
Both purified and membrane-bound 5'-nucleotidases (EC 3.1,3.5) from guinea pig skeletal muscle and bull seminal plasma are inhibited by Concanavalin A (Con A). 5'-Nucleotidase purified from skeletal muscle is inhibited by Con A by an apparent uncompetitive process (K'i = 160 nM), while the lectin inhibits the particulate enzyme by an apparent non-competitive process (Ki = K'i = 50 nM). 5'-Nucleotidase purified from bull seminal plasma is inhibited by Con A by an apparent non-competitive process (K'i = Ki = 270 nM), while the membrane-bound enzyme is subjected to a mixed type inhibition by the lectin (K'i greater than Ki; 30 and 14 nM, respectively). The enzyme purified from skeletal muscle exhibits a significant cooperativity in the interaction with Con A. The inhibition of bull seminal plasma particulate 5'-nucleotidase brought about by Con A is not completely reversed by addition of alpha-methyl-D-mannoside.  相似文献   

11.
Y Hou  Q Gou  M Wu 《Human heredity》1992,42(6):380-383
The Han population in Chengdu, China, was investigated for genetic polymorphisms of alpha-2-HS-glycoprotein (A2HS), group-specific component (GC) and orosomucoid (ORM) using isoelectric focusing followed by immunofixation. The allele frequencies were: A2HS*1 = 0.6958,A2HS*2 = 0.3042, GC*1F = 0.4021, GC*1S = 0.3182, GC*2 = 0.2745, GC*1A = 0.0052, ORM1*F1 = 0.7028, ORM1*S = 0.2762, ORM1*F2 = 0.0210, ORM2*A = 0.9965, ORM2*Var = 0.0035.  相似文献   

12.
X-ray quality crystals of a soluble murine class I H-2Kb molecule complexed with three different peptide antigens were grown in several forms by streak seeding and macroseeding methods. Co-crystals with VSV-8 (RGYVYGQL), OVA-8 (SIINFEKL) and SEV-9 (FAPGNYPAL) peptides were grown either from NaH2PO4/HPO4 or from polyethylene glycol 4000 within the pH range 5.0 to 7.5, with the use of 4-methyl-2-pentane diol (MPD) as an additive. The VSV-8 crystals grew in space groups P1, with cell dimensions a = 63.1 A, b = 69.1 A, c = 72.0 A, alpha = 89.9 degrees, beta = 77.1 degrees, gamma = 123.3 degrees and P2(1)2(1)2, with a = 138.1 A, b = 88.6 A, c = 45.7 A, and diffract to 2.9 and 2.3 A, respectively. Crystals of the SEV-9 complex grew from similar crystallization conditions to those of the orthorhombic VSV-8 complex with similar cell parameters and diffract to at least 2.5 A resolution. Crystals of the OVA-8 complex were obtained from either phosphate (space group C2, a = 118.7 A, b = 61.6 A, c = 85.3 A, beta = 108.4 degrees) or polyethylene glycol (space group P1, a = 64.5 A, b = 71.0 A, c = 66.3 A, alpha = 89.7 degrees, beta = 95.7 degrees, gamma = 123.3 degrees) and diffract to 3 A resolution. The crystallization procedures used here significantly increased the rate and production of X-ray quality crystals.  相似文献   

13.
Boc-L-Asu-L-Ala-Gly-OMe crystallizes in the monoclinic space group P2(1) with cell dimensions a = 14.315 (3) A, b = 9.280 (2) A, c = 14.358(3) A, beta = 103.63(1) A, V= 1853.4 (9) A3, with two molecules in the asymmetric unit. The conformation of the two molecules is characterized by a type II' beta-bend, similar to that predicted earlier by potential energy calculations, stabilized by an intramolecular hydrogen bond. I.r. and 1H-n.m.r. data show that the folded conformation is also stable in chloroform solution.  相似文献   

14.
The oxygen atom transfer reactivity of Tp( *)MoO(2)(SPh) (1) (where Tp( *)=hydrotris-(3,5-dimethylpyrazol-1-yl)borate) with trimethyl phosphine (PMe(3)) has been investigated. The reaction proceed through a diamagnetic phosphoryl intermediate complex, Tp( *)MoO(SPh)(OPMe(3)) (2), which has been isolated and characterized by IR, NMR, UV-visible spectroscopy, and mass spectrometry. The molecular structure of 2 has been determined by X-ray crystallography. The complex crystallizes in monoclinic (P2(1)/n) space group, a=19.81 (1)A, b=11.1 (4)A, c=18.416 (5)A, beta=121.2 (3) degrees , V=3463.8 (25)A(3) with Z=4. In acetonitrile, complex 2 exchanges its phosphoryl ligand with a solvent molecule resulting in Tp( *)MoO(SPh)(MeCN) (3), which has been isolated and also characterized spectroscopically and by X-ray crystallography. Compound 3 crystallizes in triclinic (P1 ) space group, a=10.159 (6)A, b=18.563 (5)A, c=7.986 (3)A, alpha=96.22 (3) degrees , beta=121.2 (3) degrees , gamma=84.64 (3) degrees , V=1452.4 (11)A(3) with Z=2. The electronic structures of the complexes have been investigated by density functional theory and the redox chemistry has been investigated by cyclic and differential pulse voltammetry. In acetonitrile, complex 2 spontaneously transforms to complex, 3 at a rate of 5.6x10(-4)s(-1).  相似文献   

15.
Human basic fibroblast growth factor (hbFGF) has been modified, with Ala3 and Ser5 substituted by glutamic acid, and the purified recombinant protein has been crystallized. The crystals are triclinic (space group P1) with unit cell parameters a = 31.0 A, b = 33.6 A, c = 34.7 A, alpha = 88 degrees, beta = 85 degrees, gamma = 76 degrees, and they diffract to at least 2 A.  相似文献   

16.
The class I major histocompatibility (MHC) antigen HLA-B27 was purified by immunoaffinity chromatography from the homozygous human B lymphoblastoid cell line LG-2. Detergent-soluble HLA-B27 was cleaved with the protease papain to remove the hydrophobic transmembrane region and the cytoplasmic tail. Crystals of the resulting water-soluble extracellular fragments were obtained in hanging drops by the vapor-diffusion method. The crystals are triclinic, space group P1, with unit cell dimensions a = 45.9 A, b = 71.0 A, c = 83.7 A, alpha = 79.4 degrees, beta = 88.5 degrees, gamma = 89.9 degrees, and diffract beyond 2.5 A resolution.  相似文献   

17.
A truncated derivative of the human c-Ha-ras protein has been crystallized from polyethylene glycol 6000 solution by a vapour diffusion technique. The rectangular prism diffracts X-rays to at least 2.5 A resolution (1 A = 0.1 nm). The unit cell is monoclinic, space group P21, with unit cell parameters of a = 50.2 A, b = 110.9 A, c = 36.4 A, beta = 97.2 degrees. The unit cell contains four molecules.  相似文献   

18.
A monoclonal antibody of the subclass IgG2a specific for canine lymphoma cells has been crystallized by vapor diffusion from polyethylene glycol 8000. the crystals, which occasionally measure nearly a millimeter on edge, have been examined by X-ray diffraction. The crystals are of triclinic space group P1 with unit cell parameters of a = 66.39 A, b = 77.34 A, c = 101.42 A, alpha = 87.60 degrees, beta = 92.55 degrees, gamma = 97.54 degrees and cell volume of V = 4.84 x 10(5) A3. There is one entire antibody molecule as the asymmetric unit of the crystals. Three-dimensional X-ray diffraction data have been collected to 2.8 A resolution and a self rotation function calculation shows a pronounced peak indicating at least an approximate non-crystallographic dyad axis.  相似文献   

19.
Endogenous alpha-amylase inhibitor from wheat has been crystallized by a microdialysis method. There are two forms of monoclinic crystal in a microdialysis cell with a space group of P2(1). The unit cell dimensions are a = 43.5 A, b = 64.8 A, c = 32.2 A, beta = 113 degrees for the rod-like crystal, and a = 42.5 A, b = 65.2 A, c = 32.2 A, beta = 112 degrees for the plate-like crystal. The former is suitable for structure analysis because it gives the sharp diffraction beyond 2.0 A resolution, and the latter tends to form a twin crystal. A heavy-atom derivative has been successfully prepared with the heavy-atom reagent K2PtCl4, and structure analysis is in progress.  相似文献   

20.
The recombinant human p38 MAP kinase has been expressed and purified from both Escherichia coli and SF9 cells, and has been crystallized in two forms by the hanging drop vapor diffusion method using PEG as precipitant. Both crystal forms belong to space group P2(1)2(1)2(1). The cell parameters for crystal form 1 are a = 65.2 A, b = 74.6 A and c = 78.1 A. Those for crystal form 2 are a = 58.3 A, b = 68.3 A and c = 87.9 A. Diffraction data to 2.0 A resolution have been collected on both forms.  相似文献   

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