摘要：
It is well known that the wild type Cu,Zn superoxide dismutase (holo SOD) catalyzes the conversion of superoxide anion to peroxide hydrogen and dioxygen. However, a new function of holo SOD, i.e., nucleolytic activity has been found [W. Jiang, T. Shen, Y. Han, Q. Pan, C. Liu, J. Biol. Inorg. Chem. 11 (2006) 835-848], which is linked to the incorporation of exogenous divalent metals into the enzyme-DNA complex. In this study, the roles of exogenous divalent metals in the nucleolytic activity were explored in detail by a series of biochemical experiments. Based on a non-equivalent multi-site binding model, affinity of a divalent metal for the enzyme-DNA complex was determined by absorption titration, indicating that the complex can provide at least a high and a low affinity site for the metal ion. These mean that the holo SOD may use a "two exogenous metal ion pathway" as a mechanism in which both metal ions are directly involved in the catalytic process of DNA cleavage. In addition, the pH versus DNA cleavage rate profiles can be fitted to two ionizing-group models, indicating the presence of a general acid and a general base in catalysis. A model that requires histidine residues, metal-bound water molecules and two hydrated metal ions to operate in concert could be used to interpret the catalysis of DNA hydrolysis, supported by the dependences of loss of the nucleolytic activity on time and on the concentration of the specific chemical modifier to the histidine residues on the enzyme. (c) 2007 Elsevier Inc. All rights reserved.
作者机构：
[Xiao, Lin-Xia; Shi, De-Qing] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticides & Chem Biol, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Shi, De-Qing] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticides & Chem Biol, Wuhan 430079, Hubei, Peoples R China.
摘要：
In the title compound, C25H26ClN6O4PS, the fused pyrazolo-triazolopyrimidine ring system is almost planar. It makes dihedral angles of 78.1 (1) and 17.1 (1)degrees, respectively, with the attached phenyl ring and 4-chlorophenoxymethyl fragment. The P atom has a distorted tetrahedral configuration. Intra- and intermolecular C-H center dot center dot center dot O and C-H center dot center dot center dot N hydrogen bonds, together with strong pi-pi stacking interactions (inter-planar distances 3.312-3.567 angstrom), stabilize the structure.
作者机构：
[Liu, Ming-Guo] China Three Gorges Univ, Coll Chem & Life Sci, Yichang 443002, Peoples R China.;Cent China Normal Univ, Key Lab Pesticides & Chem Biol, Wuhan 430079, Peoples R China.
通讯机构：
[Liu, Ming-Guo] C;China Three Gorges Univ, Coll Chem & Life Sci, Yichang 443002, Peoples R China.
摘要：
The title compound, [Co(C17H14P)2]BF4, was obtained by the anion exchange of 1,1′-bis(diphenylphosphino)cobaltocenium chloride with sodium tetrafluoroborate. Both the cation and anion lie on crystallographic twofold axes which run through the CoIII ion, and both the B atom and one F atom of the anion, respectively. Three of the F atoms of the BF4− anion are disordered equally over two sites. The two diphenylphosphine ligands are trans to each other with respect to the CoIII ion. The crystal structure contains weak C—H...F interactions.
期刊：
JOURNAL OF SEPARATION SCIENCE,2007年30(15):2506-2512 ISSN：1615-9306
通讯作者：
Wang, Xuedong
作者机构：
[Wang, Xuedong] Cent China Normal Univ, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Coll Life Sci, Wuhan 430079, Peoples R China.
通讯机构：
[Wang, Xuedong] C;Cent China Normal Univ, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
作者机构：
[Peng, Jianxin] Cent China Normal Univ, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Inst Entomol, Minist Educ, Wuhan 430079, Peoples R China.
通讯机构：
[Peng, Jianxin] C;Cent China Normal Univ, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.
关键词：
AfMNPV;Caspase 3;Cyclosporin A;Cytochrome c;Spodoptera litura cell line (SL-ZSU-1, SL-1)
摘要：
We investigated the influence of cytochrome c on apoptosis induced by Anagrapha (Syngrapha) falcifera multiple nuclear polyhedrosis virus (AfMNPV). Microscopic observation revealed that infection of SL-1 cells with AfMNPV resulted in apoptosis, displaying apoptotic bodies in fluorescent-stained nuclei of AfMNPV-infected SL-1cells. Western blot analysis demonstrated that AfMNPV-induced apoptosis in insect SL-1 cells was significantly inhibited by cyclosporin A which blocked a translocation of cytochrome c from the mitochondria to the cytosol. As determined by using AC-DEVD-AFC as substrate, the activity of caspase-3 in AfMNPV-induced cells was detected as early as 4 h post infection, gradually increased with time extension, and reached a highest level after 16 h of infection. However, activity of caspase-3 in apoptotic cells decreased in the presence of cyclosporin A (30 μM), indicating that activation of caspase-3 in SfaMNPV-induced cells was dependent on the release of cytochrome c from the mitochondria. In addition, cyclosporin A could markedly inhibit mitochondrial transmembrane potential (ΔΨm) disruption in undergoing apoptotic cells. These data indicate that cytochrome c plays a key role in AfMNPV-induced apoptosis in S. litura cells and may be required for caspase activation during the induction of apoptosis.
摘要：
Ten substituted benzoyl aminopropyl silatranes have been synthesized by the reaction of aminopropyl silatrane with various substituted benzoyl chlorides. IR, (HNMR)-H-1 and elemental analysis confirmed their structures. The antibacterial test showed that they were efficient against Cucumber Mildew.
摘要：
Organocatalytic asymmetric direct aldol reactions in brine with high diastereo- and enantioselectivities, using a readily available bifunctional amide catalyst, were developed.
作者机构：
[杨劭; 杨娇艳; 肖敏] College of Life Sciences, Central China Normal University, wuhan, 430079, China;[肖文精] College of Chemistry, Central China Normal University, wuhan, 430079, China
通讯机构：
[YANG, S.] C;College of Life Sciences, , wuhan, 430079, China
作者机构：
The Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
会议名称：
第三届“农药与环境安全”国际学术研讨会暨第七届“植物化学保护和全球法律一体化”国际研讨会(3rd International Symposium on Pesticide and Environmental Safety & 7th International Workshop on Crop Protection Chemistry and Regulatory Harmonization)
会议时间：
2007-10-09
会议地点：
北京
会议论文集名称：
第三届“农药与环境安全”国际学术研讨会暨第七届“植物化学保护和全球法律一体化”国际研讨会（3rd I
摘要：
Optically active α-substituted phenoxyacetyloxy and aroyloxy phosphonates have been synthesized via catalytic asymmetric hydrogenation of the corresponding prochiral α, β- unsaturated phosphonates using Rh (I)/(R, R)-Me-DuPhos as the catalyst in methanol at 18℃. The asymmetric hydrogenation reaction exhibits excellent enantioselectivity with enantiomeric excesses from 91％ to 96％.
摘要：
Nanometer titanium dioxide immobilized on silica gel (immobilized nanometer TiO2) was prepared by the sol-gel method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The adsorptive potential of immobilized nanometer TiO2 for rare earth elements (REEs) was assessed in this work. The REE ions can be quantitatively retained by immobilized nanometer TiO2 at a pH range of 6–9, and 0.5 mol L−1 HNO3 was sufficient for complete elution. A method has been developed for the determination of trace REEs based on preconcentration with a microcolumn packed with immobilized nanometer TiO2 and determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The material showed relatively high chemical stability towards the action of acidic solutions. The packed microcolumn used in proposed procedure did not show any over pressure or swelling and can be used up to at least 20 adsorption-elution cycles without decrease in the performance. The optimum experimental parameters for preconcentration of REEs, such as pH of the sample, sample flow rate and volume, elution solution and interfering ions, have been investigated. The detection limits for REEs was between 3 and 57 ng L−1, and the relative standard deviations (RSDs) for the determination of REEs at 10 ng mL−1 level were found to be less than 6% when processing 100 mL sample solution. The method has been successfully applied to the determination of trace REEs in some environmental samples.
