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Molecular dynamics simulation of the transmembrane subunit of BtuCD in the lipid bilayer

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science china(Life sciences) 2010年第5期53卷 620-630页

作者： SUN TingGuang1,2.LIU Ming1,CHEN WeiZu1 & WANG CunXin1 1college of Life science and Bio{2.,Beijing University of technology,Beijing 10012.,china 2.epartment of biological and chemical {2.,Guangxi University of technology,Liuzhou 545006,china 1. college of Life science and Bio{2. Beijing University of Technology Beijing 100124 China2. Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 China

Based on the crystal structure of the vitamin B12.transporter protein of Escherichia coli(BtuCD) a system consisting of the BtuCD transmembrane domain(BtuC) and the palmitoyloleoyl phosphatidylcholine(POPC) lipid bilayer was constructed in silica,and a more-than-57-nanosecond molecular dynamics(MD) simulation was performed on it to reveal the intrinsic functional motions of *** results showed that a stable protein-lipid bilayer was obtained and the POPC lipid bilayer was able to adjust its thickness to match the embedded BtuC which underwent relatively complicated *** results may help to understand the mechanism of transmembrane substrate transport at the atomic level.

关键词： BtuCD POPC functional motion principal component analysis

Effects of lanthanum on calcium-activated K^+ currents and its kinetics in MC3T3 cells

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science china Chemistry 2010年第6期53卷 1281-1286页

作者： ZHANG LiPing1,2.& YANG Pin1 1Key Laboratory of chemical Biology and Molecular engineering of Ministry of Education Institute of Molecular {2.,Shanxi University,Taiyuan 030006,china 2.4} of Environment and Safety,Taiyuan University of {2. and technology,Taiyuan 03002.,china 1. Key Laboratory of chemical Biology and Molecular engineering of Ministry of Education Institute of Molecular science Shanxi University Taiyuan 030006 China2. College of Environment and Safety Taiyuan University of Science and Technology Taiyuan 030024 China

Using the whole cell patch-clamp technique,we studied the effects of La3+ on calcium-activated K+ currents and its kinetics of activation and inactivation in non-excitable MC3T3 *** results showed that the calcium-activated outward K+ currents were promoted with increasing concentration of Ca2. in the pipette solution and a voltage- and Ca2.-dependent ***3+ in the bath solution inhibited the currents in a concentration-dependent manner and the inhibition EC50 was 8.2. ± 1.45 μmol/*** the concentration of 50 μmol/L,La3+ significantly changed the Vh of the activation curve and shifted the activation curve to more positive potentials,but shifted the inactivation curve to more negative *** had no effect on the slope factor k of the activation and inactivation *** currents inhibition could induce a series of physiological and molecular biological functions,presumably because of its ability to depolarize the plasma membrane and enhance cell excitability,resulting in increasing Ca2. influx and cytoplast Ca2. *** process may be one of the molecular mechanisms by which La3+ affects the cell growth and function of MC3T3 cells.

关键词： MC3T3 cell potassium ion channel La3+ patch-clamp technique

Induced electric fields and plasmonic interactions between a metallic nanotube and a thin metallic film

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 38-43页

作者： LI HongJian 1,2., FU ShaoLi 1 , XIE SuXia 1,2., XU HaiQing 1 , ZHOU Xin 1,2.& WU JinJun 1 1 college of Physics science and {2., Central South University, Changsha 410083, china 2.college of Materials science and engineering, Central South University, Changsha 410083, china 1. college of Physics science and {2. Central South University Changsha 410083 China2. College of Materials Science and Engineering Central South University Changsha 410083 China

We have numerically simulated the induced electric fields and the plasmonic interactions of a metallic nanotube near a thin metallic film. Our study shows that the energies and intensities of the plasmon resonances depend strongly on the aspect ratio (the ratio of the inner to outer radius) of the nanotube as well as the separation between the center of the nanotube and the upper surface of the metallic film and the thickness of the film. The enhancement of the induced electric field of this system reaches as high as 10 4 orders of magnitude and its field distribution is characterized by waveguide-mode resonance. The report proposes that these phenomena can be applied to designing surface enhanced spectroscopies such as surface enhanced Raman spectroscopy for efficient chemical and biological sensing.

关键词： metallic nanotube virtual state plasmons extinction spectrum

Structure and Infrared Radiation Property of Co_(1-x)ZnxFe_2._4 Ferrites by XAFS Analysis

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Journal of Wuhan University of technology(Materials science) 2009年第6期24卷 907-911页

作者：张英 Inorganic Materials Department College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou China

Co1-xZnxFe2.4 ferrites were prepared by solid state reaction. The microstructure and performance were studied by X-ray diffraction, X-ray absorption fine-structure analysis and IRE-2.infrared radiant test. It is found that infrared radiance show a nonlinear change with x, exhibiting the infrared radiance of this material improved and the average radiance in the 8-14 μm waveband reached 0.91. The Co^3＋ and Zn^2. ions are found to occupy both tetrahedral and octahedral sites, and correspondingly, the fraction of Fe^3＋ ions in B-site decreases nonlinearly in ferrites. The lattice parameters are found to concern with Zn^2., and the activation energy deduces from crystal strain and crystal vibrate increases with content Zn^2.. The redistribution of the Co^3＋ and Zn^2. ions between tetrahedral and octahedral sites is related to the providing a selective tetrahedral and octahedral sites infrared radiance of Co1-xZnxFe2.4 ceramics with increasing x.

关键词： ferrites XAFS crystal structure infrared radiation property

biological decomposition of Na_2._2._3 into sulfur by a newly isolated facultative thermophilic alkaline desulphuricant strain

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science china Chemistry 2009年第2期52卷 226-230页

作者： ZHANG JianBin1,ZHANG Tong2.MA Kai2.ZHANG PengYan2.LI Qiang2.& WEI XiongHui1 1 Department of Applied Chemistry,college of Chemistry & Molecular engineering,Peking University,Beijing 100190,{2. 2.college of chemical engineering,Inner Mongolia University of technology,Huhhot 010051,{2. 1. Department of Applied Chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China 2. college of chemical {2. Inner Mongolia University of Technology Huhhot 010051 China

A facultative thermophilic alkaline desulphuricant strain named GDJ-3 was isolated from neutral soils,enriched on sulfur synthetic medium,and detected in previous *** and chemotax-onomic analyses and 16s RNA gene sequencing showed that the strain was in good agreement with Alpha proteobacterium sp.(97%) and ochrobactrum sp.(98%).The regenerative processes of the solu-tion containing sulfur compounds(SCS) from the strain through an orthogonal test were investigated to get the optimum regenerative *** results showed that regenerative temperature,air flow,and stirring speed of the agitator were the main three variables influencing the regenerative processes of the *** optimum regenerative efficiency of the SCS from the strain was obtained when tem-perature,air flow,and stirring speed of the agitator were 318.2.K,3.0 L/min,and zero r/min,*** this condition,when the cell concentration of the strain was adjusted to 107/mL,the concentra-tions of Na2.2.3 and Na2. in the SCS decreased from 112.68 g/L to 96.88 g/L and from 0.87 g/L to 0.11 g/L in 9.5 ***,XRD spectrum shows that sulfur was formed in the regeneration *** results suggest that the strain has potential application to the regeneration of the industrial so-lution containing sulfur compounds.

关键词： bio-desulfurization thermophiles optimization biocomposition orthogonal test

The expert system of genotype discrimination for D5S818 locus based on near-infrared spectroscopy-principal discriminant variate

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Journal of Pharmaceutical Analysis 2012年第2期2卷 117-122页

作者： Zai-Zhen Wu a,Jian-Hua Tang a,Bin Zhang a,Li-Ping Guo b,Hong-Ping Xie a,Bing-Ren Gu c a college of Pharmaceutical sciences,Soochow University,{2. 2.512.,china b college of Chemistry and chemical engineering,Chongqing University of science and technology,Chongqing 401331,china c {2. Institute for Drug Control,{2. 2.5002.china college of Pharmaceutical sciences Soochow University Suzhou 215123 China. college of Chemistry and chemical {2. Chongqing University of Science and Technology Chongqing 401331 China. suzhou Institute for Drug Control Suzhou 215002 China.

This paper studied the expert system of genotype discrimination for the STR locus D5S818 based on near-infrared spectroscopy-principal discriminant variate (PDV).Six genotypes,*** 10-10,10-11,11-11,11-12.11-13 and 13-13,were selected as research *** on the optimum polymerase chain reaction (PCR) conditions,about 54 measuring samples for each genotype were obtained;these samples were tested by near-infrared spectroscopy *** differences between homozygote genotypes and heterozygote ones,and differences of the total number of core repeat units between the six genotypes,two types of genotyping-tree structure were constructed and their respective PDV models were studied using the near-infrared spectra of the samples as recognition ***,based on the classification ability of these two genotyping-tree structures,an optimum expert system of genotype discrimination was built using the PDV *** result demonstrated that the built expert system had good discriminability and robustness;without any preprocessing for PCR products,the six genotypes studied could be discriminated rapidly and *** provided a methodological support for establishing an expert system of genotype discrimination for all genotypes of locus D5S818 and other STR loci.

关键词： Short tandem repeat Near-infrared spectroscopy Principal discriminant variate Genotyping-tree structure Expert system

Hydrogen metabolic pathways of Rhodospirillum rubrum under artificial illumination

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Chinese science Bulletin 2010年第1期55卷 32-37页

作者： ZHU RuiYan1,2.3 & LI JiLun1 1 college of biological {2.s, State Key Laboratory for Agrobiotechnology, china Agricultural University, Beijing 100193, china 2.college of Environmental and chemical engineering, Yanshan University, Qinhuangdao 066004, china 3 engineering Research Center for Bioenergy of Hebei Province, Qinhuangdao 066004, china college of biological {2.s State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China college of Environmental and chemical {2. Yanshan University Qinhuangdao 066004 China engineering Research Center for Bioenergy of Hebei Province Qinhuangdao 066004 China

Multiple enzymes involved in hydrogen metabolism have been detected in photosynthetic bacterium Rhodospirillum rubrum un-der various growth conditions. To investigate hydrogen metabolic pathways and the contribution of each pathway to hydrogen photoproduction in R. rubrum under the artificial illumination condition, three mutants were constructed, including nifHanfDG double mutant lacking both Fe-nitrogenase and Mo-nitrogenase, anfDG mutant lacking Fe-nitrogenase and nifHhupL double mu-tant (uptake hydrogenase deficient mutant). Comparison of the hydrogen production of these 3 mutants with R. rubrum wild type and the uptake hydrogenase deficient mutant showed that there was a third pathway involved in hydrogen production besides Mo-nitrogenase and Fe-nitrogenase, which mainly contributed to hydrogen evolution. Only a small portion of hydrogen was gen-erated by the third pathway. The hydrogen produced by Mo-nitrogenase, Fe-nitrogenase and the third pathway was about 93.5%, 4.9% and 1.5%, respectively, while the hydrogen consumed by uptake hydrogenase was about 13.3%. The investigation of the formate-linked hydrogenase activity indicated that the third pathway for hydrogen production was not mediated by the for-mate-linked hydrogenase, but probably by some unknown enzyme.

关键词：氢代谢人工照明代谢途径红螺菌固氮酶脱氢酶突变体体吸收

Expressed sequence tag analysis and cloning of trehalose-6-phosphate synthase gene from marine alga Laminaria japonica(Phaeophyta)

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Acta Oceanologica Sinica 2012年第6期31卷 139-148页

作者： XUAN Jinsong 1,4,FENG Yanbin 1,WENG Manli 1,ZHAO Ge 1,SHI Jinfeng 1,YAO Jianting 2.WANG Xiuliang 2.GUO Baotai 3,QIAO Lixian 3,DUAN Delin 2.WANG Bin 1 1 The State Key Laboratory of Plant Genomics,Institute of Genetics and Developmental Biology,Chinese Academy of sciences,Beijing 100101,china 2.The State Key Laboratory of Marine Biology,Institute of Oceanology,Chinese Academy of sciences,Qingdao 2.6071,china 3 college of Life sciences,Qingdao Agricultural University,Qingdao 2.6109,china 4 Department of biological science and engineering,School of chemical and biological engineering,University of science and technology Beijing,Beijing 100083,china 1. The State Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China 4. Department of biological science and {2. School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China 2. The State Key Laboratory of Marine Biology Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 3. college of Life sciences Qingdao Agricultural University Qingdao 266109 China

A high quality cDNA library was constructed from the brown alga Laminaria japonica,with the titer of 1.2.10 5 pfu/*** average insert size of the cDNA library is about 1.6 *** the cDNA library,591 cDNA clones were randomly selected and *** a result,574 EST(expressed sequence tag) sequences were *** of the 574 ESTs were submitted to the dbEST database section of GenBank with the accession numbers from CX942.2. to *** cDNA library was screened with a α-32.p labeled 453 bp T P S gene probe,which is a partial sequence yielded from Porphyra *** positive cDNA clones were screened and the sequencing data showed that these four cDNA clones covered majority of *** TPS cDNA *** PCR amplification,sequencing and assembling,the entire ORF(open reading frame) sequence of the T P S gene was obtained,which was named *** encodes a protein containing 908 amino acids with a calculated molecular mass of 101 674 *** LjTPS gene was successfully expressed in *** and *** LjTPS gene has potential application both in plant breeding to stress tolerance and in deciphering the T P S gene function and mechanism to stress tolerance.

关键词： cDNA library comparative study expressed sequence tag(EST) analysis Laminaria japonica trehalose-6-phosphate synthase(TPS) T P S gene

Experimental study on pressurized activated sludge process for high concentration pesticide wastewater

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Journal of Environmental sciences 2010年第9期22卷 1342-1347页

作者： Zanfang Jin, Zhiyan Pan, Shangqin Yu, Chunmian Lin college of biological and Environmental {2., Zhejiang University of technology, Hangzhou 310032. china. [a] college of biological Environmental engineering Zhejiang University of Technology Hangzhou 310032 China

Pressurized biochemical process derived from traditional activated sludge processes is an innovative technology for wastewater treatment. The main advantage of the pressurized process is that the oxygen transfer barrier can be overcome by increasing the dissolved oxygen level. In this study, high concentration pesticide wastewater was treated by pressurized activated sludge process. It was found that the removal of chemical oxygen demand （COD） increased steadily with the increase of operating pressure, aeration time, and sludge concentration. When the operation pressure was 0.30 MPa and the aeration time was 6 hr, 85.0%-92.5% COD, corresponding to an effluent COD of 2.0-370 mg/L, was removed from an influent COD of 2.00-5000 mg/L. The obtained outlet COD concentration was lower than 350-450 mg/L for the identical process operated under the atmospheric pressure. In addition, pressurized biochemical process could produce a higher COD volumetric loading rate at 5.8-7.6 kg COD/（m^***）, compared with 2.0-2.8 kg COD/（***） using the same equipment at the atmospheric pressure. The COD concentration followed a modified Monod model with Vmax 2.31 day-1 and Ks 487 mg/L.

关键词： pressurized biochemical process pesticide wastewater activated sludge kinetics