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Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science China chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3.1. College of chemistry & Environment Protection Engineering, Southwest {2. for Nationalities, Chengdu 610041, China 2. TH-UNIS Insight Co., Ltd., {2. 100085, China {3., ministry of education, department of chemistry, tsinghua university, beijing 100084, China 1. College of chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. key laboratory of bioorganic phosphorus chemistry & chemical biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 3.%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

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Hexafluoro-2.propanol as a potent cosolvent for chemical ligation of membrane proteins

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Science China chemistry 2011年第1期54卷 110-116页

作者： SHEN Fei,TANG Shan & LIU Lei department of chemistry,university of Science and Technology of China,Hefei 2.2.02.,China key {{2. of bioorganic phosphorus chemistry and chemical biology,ministry of education {12. of chemistry,{1{2. university.beijing 100084,China 1. department of chemistry University of Science and Technology of China Hefei 230026 China2. Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Ministry of Education department of chemistry Tsinghua University Beijing 100084 China

The study on membrane proteins is an important challenge mainly because of their very poor solubility in various *** traditional recombinant expression strategy and the native chemical ligation method both have difficulty in generating sufficient amounts of desired proteins with high *** studies have shown that multiply fluorinated alcohols exhibit good ability to dissolve difficult peptide sequences,especially hexafluoro-2.propanol (HFIP).In the present study we systematically studied the capability of solvents containing different percentage of HFIP in dissolving transmembrane *** both HPLC and UV analyses we concluded that 60% HFIP/8 M urea constituted a good solvent *** this solvent system we also optimized conditions to perform native chemical ligation (NCL).Under the optimized conditions we successfully achieved NCL’s for both dipeptide formation and the synthesis of a model protein (Trifolitoxin).These results suggested that HFIP was a potential cosolvent that could be used in the ligation of poorly soluble peptides for the generation of membrane proteins.

关键词： membrane protein native chemical ligation alternative solvent hexafluoro-2.propanol

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Preparation of recombinant firefly luciferase by a simple and rapid expression and purification method and its application in bacterial detection

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Journal of Pharmaceutical Analysis 2010年第2期22卷 97-101页

作者： Qin Xiao1,2.Hui Chen2.Jin-Ming Lin2.1. College of Ocean,Hebei Agricultural university,Qinhuangdao 066003.2. The {2. laboratory of {3. phosphorus chemistry & chemical biology,department of chemistry,tsinghua university,beijing {13.,China. College of Ocean Hebei Agricultural University Qinhuangdao 066003 China key laboratory of {2. {3. chemistry and chemical biology Department of Chemistry Tsinghua University Beijing 100084 China

A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection. A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET2.a expression vector and the recombinant protein was produced in Escherichia coli BL2.. The recombinant luciferase,equipped with a polyhistidine affinity tag,was purified by immobilized metal ion affinity chromatography (IMAC). The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture. Experiments on the recombinant luciferase also showed that the relative light units (RUL) of the enzyme were 5.8×108,and the specific activity was 2.9×1010 RLU/mg. By applying adenosine triphosphate (ATP) bioluminescence to detection of the coin bacteria using the recombinant protein,the ATP content of bacteria was 9.48×10-16mol/mL,and was identical to the bacteria counts (4500CFU/mL) in order of magnitude. Taken together,our results provided a simple and efficacious method of the preparation of recombinant luciferase,which could be applied in the determination of bacteria via ATP bioluminescence.

关键词： ATP bioluminescence bacterial detection expression firefly luciferase purification

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Evaluation of non-covalent interaction between Seryl-Histidine dipeptide and cyclophilin A using NMR and molecular modeling

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Science China chemistry 2010年第9期53卷 1987-1993页

作者： LIU Yan1,SHI YanHong2,LIU XiaoXia1,LIN MingKun1,LIN DongHai1,2 & ZHAO YuFen1,3 1key laboratory for chemical {2. of Fujian Province,department of chemical {2.,department of chemistry,College of chemistry and chemical Engineering,Xiamen university,Xiamen 361005,China 2Shanghai Institute of Materia Medica,Shanghai Institutes of Biological Sciences,Chinese Academy of Sciences,Shanghai 201203,China 3key laboratory for bioorganic phosphorus chemistry and chemical {2.,ministry of education,department of chemistry,School of Life Sciences and Engineering,{2.} university,{2.} {2.},China 1. key laboratory for {2. {3. of Fujian Province Department of Chemical Biology Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. Shanghai Institute of Materia Medica Shanghai Institutes of Biological Sciences Chinese Academy of Sciences Shanghai 201203 China3. Key Laboratory for Bioorganic Phosphorus Chemistry and Chemical Biology Ministry of Education Department of Chemistry School of Life Sciences and Engineering Tsinghua University Beijing 100084 China

Seryl-Histidine dipeptide(Ser-His) has been previously reported to be capable of cleaving DNAs and carboxyl esters,as well as *** protein cleavage mechanism has not been addressed *** an initial step of protein cleavage activity,the non-covalent binding affinity of Ser-His for proteins is a crucial *** this work,we took cyclophilin A(CyPA) as a substrate protein,and evaluated the non-covalent interaction between CyPA and Ser-His using a combination of NMR spectroscopy and molecular modeling *** independent Ser-His binding sites on CyPA were detected using 15N-1H heteronuclear single-quantum coherence(HSQC) *** binding site binds one Ser-His *** constants,Kd1 and Kd2.were estimated to be 2.07 and 6.66 mmol/L,respectively,indicative of the weak non-covalent interaction between Ser-His and *** on molecular modeling results,we suggest that both the α-amino and the side chain hydroxyl group of Ser-His are crucial for the non-covalent interaction between Ser-His and *** work sheds light on the molecular mechanism of Ser-His and its analogues cleaving proteins.

关键词： Ser-His cyclophilin A HSQC non-covalent interaction binding sites

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Design,Synthesis and biological Activity of novel steroid and Bioconjugates

Design,Synthesis and biological Activity of novel steroid an...

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第五届全国化学生物学学术会议

作者： Yong JU key laboratory of {2. {3. chemistry & chemical biology,ministry of education,department of chemistry,tsinghua {12.,{13.,100084

＜正＞Steroids play very important role in the life of animals and plants and steroid phosphates are also important biological *** to their lipophilic character,lymphocyte membrane affinity,and the ability of binding to low density lipoproteins,design and synthesis of steroidal bioconjugates as bioactive pro-drugs become important,because such drugs should have increased lipophilicity and enhanced permeability through cell

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Tertiary Enamides Are Unique Building Blocks in the Synthesis of Natural and Unnatural Bioactive N-Heterocyclic Compounds

Tertiary Enamides Are Unique Building Blocks in the Synthesi...

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中国化学会第十届全国有机合成化学学术研讨会

作者： Mei-Xiang Wang key laboratory of {2. {3. chemistry and chemical biology(ministry of education), department of chemistry,tsinghua university,{12. {13.,China

＜正＞Enamides are enamine variants that are stable and occur as natural *** to the electronic effect of an electron-withdrawing group on nitrogen,the delocalization of the lone pair electrons on nitrogen atom into carbon-carbon double bond is alleviated,leading to the decrease of electron density and therefore the nucleophilicity of enaminic *** secondary enamides,the enamides bearing an N-H moiety,are the aza-ene components that undergo addition reactions towards very active electrophiles,tertiary enamides have been known as inert entities in nucleophilic *** notion has however been challenged in recent *** the synthesis of clausena alkaloids,we discovered that tertiary enamides act as a unique nucleophilic component to react intramolecularly with epoxide. The discovery has led us to systematically study the nucleophilic reactivity of tertiary enamides in organic *** this talk,I will present the synthesis of clausena alkaloids including five-membered neoclausenamide and clausenamide,six-membered homoclausenamide,eight-memberedζ-clausenamide, and their analogs based on diverse reactivities of tertiary *** asymmetric nucleophilic reactions of enamides in the synthesis of highly enantioenriched N-heterocyclic compounds that are relevant to natural and bioactive products will also be highlighted.

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EFFECTS OF PHOSPHORYLATION ON THE CONFORMATION OF PEPTIDE AND PROTEIN

EFFECTS OF PHOSPHORYLATION ON THE CONFORMATION OF PEPTIDE AN...

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第17届国际磷化学大会

作者： Yan-Mei Li Yu-Fen Zhao key laboratory of {2. {3. chemistry and chemical biology (ministry of education) department of chemistry tsinghua {12. {13. 100084

＜正＞The regulation of biochemical activity by protein post-translational modifications is a pervasive cellular control mechanism. Protein phosphorylation is a key posttranslational modification

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Protein misfolding and inhibitor design

Protein misfolding and inhibitor design

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第六届全国化学生物学学术会议

作者： Li Yan-mei~* key laboratory of {2. {3. chemistry and chemical biology(ministry of education),department of chemistry,tsinghua {12.,{13. 100084,P.R.China

＜正＞Great deals of aetiologically distinct diseases have been linked by the likehood that they result from the progressive misfolding of specific proteins into aggregates that can cause cell *** are some secreted proteins that can,under abnormal circumstances,be converted in part to highly stable extracellular *** include amylin in the diabetic pancreas and proteins such as the amyloid -peptide（A） and Tau in Alzheimer’s disease.

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Peptidase Mimics to Selectively Degrade β-Amyloid of Alzheimer's Disease

Peptidase Mimics to Selectively Degrade β-Amyloid of Alzhei...

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第五届全国化学生物学学术会议

作者： Yan-Mei LI key laboratory of {2. {3. chemistry & chemical biology(ministry of education),department of chemistry,tsinghua {12.,{13. 100084,P.R.China,

The misfolded proteins are involved in the pathogenesis of human *** major representative of these proteins is β-amyloid peptide(Aβ)in Alzheimer’s disease(AD).The central theory for the cause of AD is the amyloid cascade hypothesis, which states that cerebral Aft accumulation is the initiating event in AD,and that the rest of the disease process results from an imbalance between Aft production and *** hypothesis implicates Aβ peptide as

关键词： Alzheimer’s disease β-amyloid peptide peptidase mimic

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Repeating Unit of O-deacetylated GXM of C. neoformans Serotype

Repeating Unit of O-deacetylated GXM of C. neoformans Seroty...

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第七届全国磷化学化工暨第四届海峡化学生物学、生物技术与医药发展讨论会

作者： Wei Zhao Yan-Mei Li Yu-Fen Zhao (key laboratory of {2. {3. chemistry and chemical biology (ministry of education) department of chemistry tsinghua university beijing 100084)

An important virulence factor of the pathogenic fungus Cryptococcus neoformans is its polysaccharide capsule. The capsular polysaccharides display various immunomodulatory effects on the host response, such as the inhibition of phagocytosis, suppression of T-cell mediated immunity, and induction of immunogenic ***, these capsular polysaccharides are able to interfere with the migration of phagocytes despite adequate stimulation of chemokine production and their concerted action accounts for the mild inflammatory response often observed in

关键词： GXM Repeating Unit of O-deacetylated GXM of C neoformans Serotype

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