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111.
Shirley P. Tolley Gideon J. Davies Mark O'Shea Mark I. Cockett Andrew J. P. Docherty Gillian Murphy 《Proteins》1993,17(4):435-437
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
112.
Single crystals were grown from affinity-purified stinging nettle lectin and from its complex with the specific trisaccharide NN′N″ -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
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In our previous work, two dopamine derivatives with benzothiazole fragment were isolated and identified from Polyrhachis dives (P. dives). Based on their characteristic structure, we used them as lead compound to carry out structural optimization and subsequent fungicidal evaluation. Here 20 dopamine derivatives with benzothiazole fragment were designed and synthesized by a facile method, and their structures were characterized by 1H-NMR, 13CNMR and HMRS. In bioassays, most of the title compounds possess potential fungicidal activities against Altenaia alternala (A. alternala) and Botrytis cinerea (B. cinerea). Especially, (E)-N-(2-(benzo[d]thiazol-6-yl)ethyl)-3-(p-tolyl)acrylamide and (E)-N-(2-(benzo[d]thiazol-6-yl)ethyl)-3-(4-(trifluoromethyl)phenyl)acrylamide displayed 29.3 mg/L and 10.7 mg/L EC50 value against A. alternala, respectively, which possessed equivalent fungicidal activities level to hymexazol. 相似文献
116.
Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献
117.
In order to explain and predict yield losses caused by European corn borer larvae, Ostrinia nubilalis Hbn. (Lepidoptera: Pyralidae), a mechanistic model was proposed to describe cavity appearance, their lengthwise extension, and their within-plant distribution. It integrates main dynamical processes of larvae: mortality, development and within-plant distribution. After its estimation and test under field conditions in 1988 and 1989, its validation, based upon X-ray photographs, is presented. This method allows cavity appearance and lengthwise extension to be followed without damaging the plants. This study confirms the relevance of the damage model and the rate of cavity lengthwise extension estimated with it. 相似文献
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Dr A Azadpour L R Brown A A Vadie 《Journal of industrial microbiology & biotechnology》1996,16(5):263-266
Virgin cores and production fluids were obtained from seven wells, ranging in depth from 805 ft to 14 492 ft, and examined for the presence of sulfate-reducing bacteria (SRB) using Rosenfeld's sulfate-reducing medium modified by using crude oil in place of lactate. Cores from an additional six wells, ranging in depth from 1160 ft to 13 337 ft were tested for SRB using the modified Rosenfeld medium and API-sulfate-reducing medium. Produced waters from five of the six wells were tested also. All of the eleven produced water samples were positive for SRB while H2S production was not detected from the core samples. 相似文献
120.
Cloning,expression, and crystallization of the V delta domain of a human gamma delta T-cell receptor.
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M. I. Lebedeva B. A. Fields H. Spits G. Panchamoorthy M. B. Brenner R. A. Mariuzza 《Protein science : a publication of the Protein Society》1996,5(12):2638-2642
T-lymphocytes recognize a wide variety of antigens through highly diverse cell-surface glycoproteins known as T-cell receptors (TCRs). These disulfide-linked heterodimers are composed of alpha and beta or gamma and delta polypeptide chains consisting of variable (V) and constant (C) domains non-covalently associated with at least four invariant chains to form the TCR-CD3 complex. It is well established that alpha beta TCRs recognize antigen in the form of peptides bound to molecules of the major histocompatibility complex (MHC); furthermore, information on the three-dimensional structure of alpha beta TCRs has recently become available through X-ray crystallography. In contrast, the antigen specificity of gamma delta TCRs is much less well understood and their three-dimensional structure is unknown. We have cloned the delta chain of a human TCR specific for the MHC class I HLA-A2 molecule and expressed the V domain as a secreted protein in the periplasmic space of Escherichia coli. Following affinity purification using a nickel chelate adsorbent, the recombinant V delta domain was crystallized in a form suitable for X-ray diffraction analysis. The crystals are orthorhombic, space group P2(1)2(1)2 with unit cell dimensions a = 69.9, b = 49.0, c = 61.6 A. and diffract to beyond 2.3 A resolution. The ability of a V delta domain produced in bacteria to form well-ordered crystals strongly suggests that the periplasmic space can provide a suitable environment for the correct in vivo folding of gamma delta TCRs. 相似文献