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Acta Biochimica et Biophysica Sinica 2006年第7期 457-466页

作者： kuan peng~1.ying lin~1.song-ping liang~(1,2*) 1.college of life science,peking University,beijing 1.0871.China 2 college of life science,Hunan Normal University,Changsha 410081,China

Huwentoxin-XI purified from the Chinese bird spider Ornithoctonus huwena is a toxin withboth antiprotease activity and potassium channel blocking *** determine its solution structure,huwentoxin-Ⅺ was expressed in a yeast eukaryotic expression system and studied by ***1.N labelingstrategy was used to facilitate the process of resonance *** nearly complete sequence-specificassignments of proton and nitrogen resonances were obtained by analyzing a series of two-dimensional（2D）and three-dimensional（3D）spectra,including DQF-COSY,TOCSY,NOESY,1.N-1. HSQC,1.N-1. HNHA,1.N-1. HNHB,1.N-1. TOCSY-HSQC and1.N-1. NOESY-HSQC *** structure analysis ofhuwentoxin-Ⅺ showed that it mainly contains an N-terminal 31.-helix from Thr3 to Arg5 and a C-terminalα-helix from Gln45 to Cys52,plus a triple-stranded antiparallel β-sheet of Glul 8-Asn23,Thr26-Ile31.*** studies provide a solid basis for the final structure determination of huwentoxin-Ⅺ.

关键词： huwentoxin-XI toxin nuclear magnetic resonance 1.N labeling sequence-specific assignment

Polycistronic strategy for cyanobacterial expression vector construction: Co-transcription of a human gene and a selective marker gene

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Progress in Natural science:Materials International 2005年第9期15卷 798-803页

作者： ZHANG Yukun1. SHI Dingji2, ZHAO Feifei1. YU Meimin1.and RU Binggen1.1. college of {1. science, peking University, beijing 1.0871. China 2. college of Marine sciences & Engineering, Tianjin University of science & Technology, Tianjin 300450, China) college of {1. science Peking University Beijing 100871 China. college of Marine {1.s & Engineering Tianjin University of Science & Technology Tianjin 300450 China

A polycistronic expression vector, pKGA-NTF1. was constructed for the cyanobacterium. Within this vector, the spectinomycin/streptomycin resistance gene (aadA) facilitated the selection of transformants when co-transcribed with favorite genes. A natural glnA gene was selected as the platform to introduce the plasmid into a neutral site of the Synechococcus sp. PCC 7002 chromosome. Function of the vector was demonstrated by the insertion of a modified human Trefoil factor 3 gene (NTF1. to upstream of the aadA gene and by the analyses of the transformed strains. Antibiotics resistance assays showed that the dicistronic expression cassette conferred high spectinomycin resistance to both the E. coli cells and the Synechococcus cells. PCR analysis and Western-blot analysis were carried out to confirm the integration and expression of the NTF1.gene, respectively. Through simple molecular manipulations, the artificial polycistronic structure described here can be conveniently used to express other favorable genes or operons in cyanobacteria, and to study the cyanobacterial gene expression as well.

关键词： cyanobacterial transformation human Trefoil factor 3 polycistronic expression Synechococcus sp. PCC 7002 vector construction.

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural science:Materials International 2007年第10期17卷 1127-1135页

作者： song Nanmeng1. Sang Jianli1.and Xu Heng2(1. Institute of Cell Biology, {1. of life science, beijing Normal University, beijing 1.0875, China 2. Emory University School of Medicine, GA 30332, USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875， China Emory University School of Medicine GA 30332 USA

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

Physiological and ultralstructural changes of Chlorella sp. induced by UV-B radiation

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Progress in Natural science:Materials International 2005年第8期15卷 678-683页

作者： YU Juan1. TANG Xuexi1., ZHANG Peiyu 1.2, TIAN Jiyuan1.and DONG Shuanglin1.1. Division of {1. science and Technology, Ocean University of China, Qingdao 266003, China 2. college of {1. sciences, Qufu Normal University, Qufu 2731.53, China) Division of life {1. and Technology Ocean University of China Qingdao 266003 China. college of {1. sciences Qufu Normal University Qufu 2731653 China

In order to investigate the mechanisms of enhanced UV-B radiation on algae, the effects of UV-B radiation on the physiological and ultrastructural changes of Chlorella sp. were examined. The results showed that UV-B radiation could inhibit the growth and photosynthesis of microalgae. UV-B radiation at lower doses increased the photosynthetic pigment (chlorophyll a (Chla) and carotenoid (Car)) contents, while at higher doses of UV-B radiation Chla and Car contents were decreased. The ultrastructure of Chlorella sp. without exposure to UV-B showed that the thylakoid lamellae were clear and regular, the stroma of its chloroplast was apparent and clear. The globules with photosynthetic pigments and the cristae of mitochondria were clearly seen. After exposure to UV-B radiation at dose of 2.88 kJ/m2, the thylakoid lamellae of Chlorella sp. were lost and dissolved, the globules which contained photosynthetic pigments in chloroplast were bleached; some mitochondria cristae were dissolved; slight plasmolysis was found in some Chlorella sp. cells. After exposure to 5.76 kJ/m2 UV-B radiation, the thylakoid was in disarray and disintegration, plasmolysis was found in most cells, and the cell wall was broken and began to fall out. Many blank areas were observed in cells, mitochondria were seriously deformed and most of the mitochondria cristae were dissolved. Also, globules containing photosynthetic pigments in chloroplast were bleached and some empty globules were found in chloroplast. Therefore, UV-B radiation could damage cell structure of Chlorella sp., and this damage increased with the dose of UV-B radiation they exposed to.

关键词： UV-B radiation physiological changes ultrastructure Chlorella sp.

Interface and properties of epoxy resin modified by elastomeric nano-particles

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science China Chemistry 2005年第2期48卷 148-155页

作者： HUANG Fan1. LIU Yiqun1. ZHANG Xiaohong1. GAO Jianming1. song Zhihai1. TANG Banghui1. WEI Genshuan2 & QIAO Jin{1.1.1. SINOPEC beijing Research Institute of Chemical Industry, beijing 1.001., China 2. Institute of Applied Chemistry, college of Chemistry and Molecular Engineering, peking University, beijing 1.0080, China Correspondence should be addressed to Qiao Jin{1. (email: jqiao@***.) 1. SINOPEC beijing Research Institute of Chemical Industry 100013 Beijing China 2. Institute of Applied Chemistry College of Chemistry and Molecular Engineering Peking University 100080 Beijing China

Study on a new composite of epoxy resin/elastomeric nano-particles (ENP) is re- ported in this paper, which shows that, in comparison with pure epoxy resin and epoxy toughened with CTBN, the composites of epoxy resin/carboxylic nitrile-butadiene ENP and epoxy resin/styrene butadiene vinyl-pyridine ENP possess both higher toughness and heat resistance. Both ENPs used in the study have an average size of less than 1.0 nm. Study on the epoxy network’s morphology and interface properties suggests that due to the chemical reaction be- tween ENP and epoxy resin and more hydrogen bonds between nitrile groups of the rubber and hydroxyl groups of the epoxy resin, stronger interaction at the larger interface may lead to the observed excellent properties of the epoxy resin toughened with ENP.

关键词： elastomeric nano-particles, epoxy resin, carboxylic nitrile-butadiene rubber, styrene butadiene vinyl-pyridine rubber, interface.

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Genetic polymorphisms of milk epithelial mucin of yaks

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Progress in Natural science:Materials International 2006年第11期16卷 1222-1226页

作者： ZHENG Yucai~1. ZHAO Xingbo~2**, JIN Suyu~1. peng Xianwen~1.and BAI Wen{1.~1.(1. college of life science and Technology, Southwest University for Nationalities, Chengdu 61.041. China 2. State Key Laboratory for Agrobiotechnology and Ministry of Agriculture Key Laboratory of Animal Genetics, Breeding and Reproduction, China Agricultural University, beijing 1.0094, China) [a]college of {1. science and Technology Southwest University for Nationalities Chengdu China [b]State Key Laboratory for Agrobiotechnology and Ministry of Agriculture Key Laboratory of Animal Genetics Breeding and Reproduction China Agricultural University Beijing China

Milk epithelial mucin (MUC1. of yaks was separated by SDS-polyacrylamide gel electrophoresis. A total of nine types of MUC1.were revealed in 427 yaks from five yak breeds including Maiwa yak, Jiulong yak, Tianzhu white yak, Qinghai yak and Tibetan yak. The molecular weights of MUC1.are from 1.3 kD to 208 kD, most of which are larger than those of bovine. Population genetic analysis shows that the gene frequency and genotype frequency of yak MUC1.differ among breeds, with relatively high gene heterozygosity. The five yak breeds studied fall into two groups according to their milk MUC1.gene frequency, suggesting that milk MUC1.exhibits specificities for local yak groups.

关键词： yak milk genetic polymorphism MUC1.

The toxicity of Cu^(2+) to Microcystis aeruginosa using dielectric spectroscopy

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science China Chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1.BAI Wei1.ZHAO KongShuang1. ZHOU YunLong2 1.0} of Chemistry,{1. Normal University,{1. 1.0875,China 2college of life science,{1. Normal University,{1. 1.0875,China 1. college of Chemistry Beijing Normal University Beijing 100875 China2. College of Life Science Beijing Normal University Beijing 100875 China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2+ solution to Microcystis *** was found that 0.04 mM Cu2+ had no effect on dielectric increment,whereas the Cu2+ concentrations above 0.1.mM decreased the value of Δε/Δε *** toxic effect of Cu2+ on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1.mM,which affected the cell membrane,suggesting that Cu2+ at the concentrations higher than 0.1.mM caused serious plasmalemma damage to *** *** addition of 1.mM Ca2+ or Mg2+ did not protect *** cells from 1.mM Cu2+ *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

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Effect of D-allethrin on proteinase activity in the midgut of the spider Pardosa pseudoannulata detected by bulk acoustic wave impedance technique

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Progress in Natural science:Materials International 2007年第12期17卷 1521-1526页

作者： Wang Zhi1. Fu Xiuqin2, Rao Liqun1.and Lu Xiangyang1.1. college of Bio{1. & Biotechnology, Hunan Agriculture University, Changsha 41.1.8, China 2. college of life {1., Hunan Normal University, Changsha 41.081. China) college of Bio{1. & Biotechnology Hunan Agriculture University Changsha 410128 China college of {1. science Hunan Normal University Changsha 410081 China

The piezoelectric bulk acoustic wave (BAW) impedance analysis method was employed to monitor in situ the proteinase-catalyzed hydrolyzation of casein and the effect of pesticide D-allethrin on the proteinase activity in the midgut of the spider Pardosa pseudoannulata, and the results obtained were verified by ultraviolet spectroscopy. The hydrolyzation was significantly increased in the presence of low-dose D-allethrin, whereas significantly inhibited in the presence of high-dose D-allethrin, and a correlation was found precisely between the enzyme activity reflected by the final frequency shift after the hydrolyzation and the concentration of D-allethrin, with a significant frequency response observed even at a 1.5×1.-5 volume ratio of D-allethrin to distilled water. The present work may have presented a novel method feasible for study on the mechanism of excitability of spiders under low-dose D-allethrin pesticide and quick detection of proteinase activity.

关键词： Pardosa pseudoannulata D-allethrin proteinase activity ultraviolet spectroscopy piezoelectric bulk acoustic wave impedance method.

Non-invasive scanning ion-selective electrode technique and its applications to the research of higher plants

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Progress in Natural science:Materials International 2007年第6期17卷 625-629页

作者： Sun Tong1. Xu Yue2, Li peng1. Yu Shangguan2 and Yin Li{1.1.1. college of life science, Capital Normal University, beijing 1.0037, China 2. Younger USA science & Technology Corporation, 7 Dayton Lane, Amherst MA 01.02, USA) [a]college of {1. science Capital Normal University Beijing China [b]Younger USA science & Technology Corporation Amherst MA USA

The process of various ions and molecules getting into and out of cells is critical for plant survival. The non-invasive scanning ion-selective electrode technique (SIET) is a non-invasive method to obtain the information of ions/molecules across membranes in plant. This technique can measure the absolute concentration of ions and molecules, and also their fluxes and directions of movement. The samples to be analyzed can be a single cell, a piece of tissue, a whole organ and even an intact seedling. This article reviews the recent progress made in plant physiology by using this technique and discusses its potentials in future studies on plant physiology.

关键词： non-invasive electrophysiology technique ion-selective electrode ion transport across membrane SIET.

Study on the drug resistance and the binding mode of HIV-1.integrase with LCA inhibitor

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science China Chemistry 2007年第5期50卷 665-674页

作者： HU Jianping1.2, CHANG Shan1. CHEN WeiZu1.& WANG CunXin1.{1. of life science and Bioengineering, beijing University of Technology, beijing 1.0022, China 2 Department of Chemistry & life sciences, Leshan Normal University, Leshan 61.004, China college of {1. science and Bioengineering Beijing University ofTechnologyBeijing 100022China Department of Chemistry & life {1.s Leshan NormalUniversityLeshan 614004China

Human immunodeficiency virus type 1.(HIV-1. integrase (IN) is an essential enzyme in the lifecycle of this virus and also an important target for the study of anti-HIV drugs. The binding mode of the wild type IN core domain and its G1.0S mutant with L-Chicoric acid (LCA) inhibitor were investigated by using multiple conformation molecular docking and molecular dynamics (MD) simulation. Based on the binding modes, the drug resistance mechanism was explored for the G1.0S mutant of IN with LCA. The results indicate that the binding site of the G1.0S mutant of IN core domain with LCA is different from that of the core domain of the wild type IN, which leads to the partial loss of inhibition potency of LCA. The flexibility of the IN functional loop region and the interactions between Mg2+ ion and the three key residues (i.e., D64, D1.6, E1.2) stimulate the biological operation of IN. The drug resistance also lies in several other important effects, such as the repulsion between LCA and E1.2 in the G1.0S mutant core domain, the weakening of K1.9 binding with LCA and Y1.3 pointing to the pocket of the G1.0S mutant. All of the above simulation results agree well with experimental data, which provide us with some helpful information for designing the drug of anti-HIV based on the structure of IN.

关键词： molecular docking, MD simulation, HIV-1 IN, drug design

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