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Metal binding discr.mination of the calmodulin Q41C/K75C mutant on Ca^(2+) and La^(3+)

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Science china Chemistr. 2010年第4期53卷 797-806页

作者： XU Kun, YANG XiaoDa & WANG Kui state key laboratory for.natural and biomimetic drugs Dep.r.ment of Chemical Biology, School of p.ar.aceutical Sciences, peking university Health Science Center. beijing 100191, china 1. state key laboratory for.natural and biomimetic drugs Peking University Health Science Center Beijing 100191 China2. Department of Chemical Biology School of Pharmaceutical Sciences Peking University Health Science Center Beijing 100191 China

Calmodulin (CaM) is a multifunctional Ca2+-binding p.otein r.gulating the activity of many enzymes in r.sp.nse to fluctuation of the intr.cellular.Ca2+ level. It has been shown that a CaM Q41C/K75C mutant (CaMSS) with a disulfide bond in the N-ter.inal domain exhibits gr.atly r.duced affinity to Ca2+. In the p.esent study, the exp.r.mental r.sults r.vealed a unique metal binding p.tter. in CaMSS towar.s La3+ and Ca2+ sep.r.tely: the mutant p.otein binds Ca2+ at site Ⅰ, Ⅲ and IV; however. it binds La3+ at site Ⅰ, Ⅱ and IV. A p.tative mechanism was p.op.sed which is the confor.ation of site Ⅱ (or.siteⅢ) of CaMSS could be alter.d and thus loses its metal ion affinity in r.sp.nse to metal binding in the op.osite ter.inal domain p.ssibly thr.ugh the long r.nge domain inter.ction. The p.esent wor. may offer.new p.r.p.ctives for.under.tanding the mechanisms of sp.cific metal ion affinity in CaM and for.CaM-based p.otein design.

关键词： calmodulin lanthanum calcium long r.nge inter.ction

3D-QSAr.study on p.enoxy-alkylamine comp.unds of α_1-adr.nocep.or.antagonist

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Chinese Science Bulletin 2001年第4期46卷 303-306页

作者： FANG Hao, LU Jingfen, XIA Lin & ZHANG LineDep.r.ment of Medicinal Chemistr., china p.ar.aceutical university, Nanjing 210009, china state key laboratory of natural and biomimetic drugs, beijing Medical university, beijing 100083, china Dep.r.ment of Medicinal Chemistr. China Pharmaceutical University Nanjing China state key laboratory of natural and biomimetic drugs Beijing Medical University Beijing China

The study of thr.e-dimensional quantitative str.ctur.-activity r.lationship.(3D-QSAr. of DDp. and its der.vatives that have been known with their.activity p.r.meter. has been develop.d using the comp.r.tive molecular.field analysis (CoMFA) method. Her., (+)-DDp. cr.stal str.ctur. was selected as the active confor.ation model and comp.r.sons between the influences of differ.nt char.e calculation methods and gr.d setup.wer. conducted. The coefficients of cr.ss-validation (q2) and r.gr.ssion (r.) ar. 0.481 and 0.997, r.sp.ctively. The standar. er.or.(SE) is 0.102. The r.sear.h r.sult suggests that the ster.c field makes mor. contr.butions to the activity than the electr.static field. This model can help.us not only in imp.oving our.under.tanding of the r.cep.or.ligand inter.ctions, but also in p.edicting the activity of der.vatives and designing new comp.unds with better.p.tency.

关键词： CoMFA. α1 -adr.nocep.or antagonist.

Br.in-der.ved neur.tr.p.ic factor.p.otects neur.ns fr.m GdCl_3-induced imp.ir.ent in neur.n-astr.cyte co-cultur.s

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中国科学：化学英文版 2010年第10期53卷 2193-2199页

作者： XIA Qing, FENG XuDong, YUAN Lan, WANG Kui & YANG XiaoDa state key laboratory of natural and biomimetic drugs and Dep.r.ment of Chemical Biology School of p.ar.aceutical Sciences, peking university, beijing 100191, china 1. state key laboratory of natural and biomimetic drugs and Dep.r.ment of Chemical Biology School of p.ar.aceutical Sciences Peking University Beijing 100191 China

Gadolinium (Gd3+) comp.exes ar. imp.r.ant contr.st agents in medical magnetic r.sonance imaging (Mr.) and of gr.at p.tential value in br.in r.sear.h. In or.er.to better.under.tand the mechanisms of the action of Gd3+ on neur.ns in the comp.ex centr.l ner.ous system (CNS), the neur.toxic actions of GdCl3 have been investigated in both neur.n monocultur. and astr.cyte-neur.n co-cultur. systems. Measur.ments of lactate dehydr.genase r.lease showed that GdCl3 causes significant cell death of monocultur.d neur.ns as a r.sult of r.active oxygen sp.cies (r.S) gener.tion and down-r.gulation of br.in-der.ved neur.tr.p.ic factor.(BDNF). However. GdCl3 does not affect the viability and BDNF exp.ession of astr.cytes. Both co-cultur.ng of neur.ns with astr.cytes and addition of BDNF amelior.ted GdCl3-induced neur.toxicity by decr.asing r.S gener.tion and facilitating r.cover. of BDNF levels. The r.sults obtained suggest that astr.cytes in the CNS may p.otect neur.ns fr.m GdCl3-induced imp.ir.ent thr.ugh secr.ting BDNF and thus up.r.gulating BDNF exp.ession and inter.er.ng with Gd3+-induced cell signaling in neur.ns. A p.ssible molecular.mechanism is suggested which should be help.ul in under.tand- ing the neur.toxic actions of gadolinium p.obes .

关键词： gadolinium br.in-der.ved neur.tr.p.ic factor BDNF co-cultur. astr.cytes neur.ns

Some inter.sting CH_2CH_3 sp.n systems in sever.l diethyl malonate indene der.vatives studied with NMr.and molecular.modeling

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Science china Chemistr. 2009年第7期52卷 937-942页

作者： ZHANG Long1, HE WeiWei1, LIANG YongMin2 & CUI YuXin1 1 state key laboratory of natural and biomimetic drugs, School of p.ar.aceutical Sciences, peking university, beijing 100191, china 2 state key laboratory of Ap.lied Or.anic Chemistr., Lanzhou university, Lanzhou 730000, china state key laboratory of natural and biomimetic drugs School of Pharmaceutical Sciences Peking University Beijing 100191 China state key laboratory of Ap.lied Or.anic Chemistr. Lanzhou University Lanzhou 730000 China

While studying the electr.p.ilic cyclization of acetylenic malonates in synthesizing malonate indene der.vatives with high r.gio and ster.o-selectivity, we found that the CH2 and CH3 p.otons of two COOCH2CH3 gr.up. in some diethyl malonate indene der.vatives showed ver. inter.sting sp.n-sp.n coup.ing and signal multip.icity. To exp.ain those p.enomena, we synthesized sever.l diethyl malonate indene der.vatives, and then used 1H NMr.sp.ctr. and molecular.modeling to investigate the CH2CH3 sp.n system of these two COOCH2CH3 gr.up. in detail. The r.sults showed that the sp.n systems of CH3CH2 of the two COOCH2CH3 gr.up. in those comp.unds may exist in differ.nt fr.ms (AMX3, ABX3 and A2X3), and the effect of the ar.matic r.ng induced by the p.enyl gr.up.at the end of the tr.p.e bond is the main r.ason r.sp.nsible for.those p.enomena.

关键词： electr.p.ilic cyclization sp.n-sp.n coup.ing signal multip.icity molecular modeling sp.n system ar.matic r.ng

MEAM p.tential with Angular.Dep.ndence for.TiAl

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r.r. Metals 2001年第1期20卷 13-17页

作者： Xiaodong Ni, Xitao Wang, Guoliang Chen (p.ysics Dep.r.ment, university of Science and Technology beijing, beijing 100083, china state key laboratory for.Advanced Metals and Mater.als, university of Science and Technology beijing, beijing 100083, china) Univ Sci & Technol beijing Dept Phys Beijing 100083 Peoples R China Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

The modified embedded atom method (MEAM) is an emp.r.cal extension of the embedded atom method (EAM) that includes angular.for.es. By fitted to the lattice constants, the cohesive ener.y, the Ap. (anti-p.ase boundar.) ener.y, and the vacancy for.ation ener.y of TiAl, an accur.te MEAM p.tential is obtained for.the TiAl system with L10 str.ctur.. The calculation r.sults of the p.op.r.ies of TiAl ar. in good agr.ement with exp.r.ments and the r.sults of fir.t p.incip.e (F.p.) calculations.

关键词： embedded atom method TiAl alloy angular.dep.ndence p.tential inter.etallics

A New Efficient Synthesis of Bisp.enol A Diether.Bis-imidazoles and Bis-benzimidazoles

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Chinese Chemical Letter. 1998年第10期9卷 917-918页

作者： Cheng He ZHOU Jun WEI Zhong Jun LI r. Gang XIE Meng Shen CAI( Dep.r.ment of Bioor.anic Chemistr., state key laboratory of natural and biomimetic drugs,School of p.ar.aceutical Sciences, beijing Medical university, Beding 100083 Dep.tment of Chemistr. beijing Med Univ Sch Pharmaceut Sci Dept Bioorgan Chem State Key Lab Nat & Biomimet Drugs Beijing 100083 Peoples R China Sichuan Union Univ Sch Sci Dept Chem Chengdu 610064 Peoples R China

A new efficient synthesis of bisp.enol A diether.bis-imidazoles and bis-benzimidazoles by br.moalkylation and imidazolylation or.benzimidazolylation two-step.r.actions fr.m commer.ial bisp.enol A, imidazole, 2-methyli... 详细信息

关键词： bisp.enol A imidazole benzimidazole ether synthesis

The synthesis, bioactivity and p.r.magnetic r.sonance of angiotensin Ⅱ and its sp.n labelled der.vative

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Chinese Science Bulletin 1997年第21期42卷 1843-1846页

作者： WANG r.i, LI Xiaoxu, HU Xiaoyu, NI Jingman, LI Changling and LU Jingfen1. Dep.r.ment of Biology, state key laboratory of Ap.lied Or.anic Chemistr., Lanzhou 730000, china 2. Dep.r.ment of Chemistr., Lanzhou university, Lanzhou 730000 3. state key laboratory of natural and biomimetic drugs, beijing Medical U-niver.ity, beijing 100083, china. Dep.r.ment of Biology State Key Laboratory of Applied Organic Chemistry Lanzhou China Dep.r.ment of Chemistr. Lanzhou University Lanzhou state key laboratory of natural and biomimetic drugs Beijing Medical University Beijing China

ANGIOTENSIN Ⅱ(Ang Ⅱ) is an imp.r.ant constituent in r.nin-angiotension system (r.S).The amino acid sequence of Ang Ⅱ is Dr.YIHp.. Ang Ⅱ p.ays an imp.r.ant r.le both inmaintenance of nor.al blood p.essur. and in occur.ence of hyp.r.ension. Ang Ⅱ binding r.-cep.or.can induce many kinds of p.ysiological effects. Sp.n labeling is an effective method thatgr.atly deep.ned the knowledge in str.ctur., movement and inter.ction of biologicalmolecules. For.examp.e, it has been used in studying inter.ction of antigen and antibody suc-

关键词： sp.n labelled angiotensin Ⅱ solid p.ase p.p.ide synthesis bioactivity electr.n sp.n r.sonance.

A Facile and Efficient synthesis for.A Ser.es of Bis(N-imidazolylethyl) Ether.

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Chinese Chemical Letter. 1998年第7期9卷 611-613页

作者： Cheng He ZHOU Yu Lan WANG r. Gang XIE Meng Shen CAI (Dep.r.ment of Bioor.anic Chemistr., state key laboratory of natural and biomimetic drugs,School of p.ar.aceutical Sciences, beijing Medical university, beijing 100083)(Dep.r.ment of Chemistr., Schoo beijing Med Univ Sch Pharmaceut Sci State Key Lab Nat & Biomimet Drugs Dept Bioorgan Chem Beijing 100083 Peoples R China Sichuan Union Univ Sch Sci Dept Chem Chengdu 610064 Peoples R China

A facile and efficient synthesis for.a ser.es of bis(N-imidazolylethyl) ether. fr.m oligo-ethyleneglycols and imidazole has been studied. All these comp.unds obtained wer. char.cter.zed by MS,(HNMr.-H-1, and elemental... 详细信息

关键词： ether glycol imidazole synthesis

A comp.tational tr.st model for.access contr.l in p.p

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Science china(Infor.ation Sciences) 2010年第5期53卷 896-910页

作者： LANG Bo state key laboratory of Softwar. Develop.ent Envir.nment, Beihang university, beijing 100191, china 1. state key laboratory of Softwar. Develop.ent Envir.nment Beihang University Beijing 100191 China

Tr.st br.ngs a new method for.building scalable and fine-gr.ined access contr.l mechanism in p.p.systems. The quantificational exp.ession of tr.st and the calculation of tr.st in a tr.st networ. ar. the basis of tr.st degr.e based access contr.l. In this p.p.r. the p.op.r.ies of tr.st is analyzed by r.fer.ing to the fr.its fr.m social science; the semantics of tr.st in the context of access contr.l is descr.bed, and a tr.st degr.e based access contr.l model named TDBAC is intr.duced. Basing on the p.op.r.ies and semantics of tr.st, a comp.tational tr.st model which includes a multilevel comp.ehensive evaluation method for.exp.essing dir.ct tr.st and calculator. for.comp.ting r.commended tr.st is p.t for.ar.. To comp.te tr.st in a tr.st networ., an algor.thm that tr.nsfor.s a tr.st networ. to a comp.table exp.ession is given. The algor.thm simp.ifies the comp.tation p.ocess and is also flexible.

关键词： tr.st management access contr.l tr.st degr.e based access contr.l comp.tational tr.st model tr.st gr.p. exp.ession