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Identification and Characterization of glnA Promoter and its Corresponding Trans-regulatory Protein GlnR in the Rifamycin SV Producing Actinomycete,Amycolatopsis mediterranei U32

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 831-843页

作者： Hao YU~(1&) Wen-Tao PENG~1 Yang LIU~1 Ting WU~2.Yu-Feng YAO~1 Ming-Xue CUI~1 Wei-Hong JIANG~1 Guo-Ping ZHAO~(1,3,4*) 1 Laboratory of Molecular Microbiology,Institute of Plant Physiology and Ecology,shanghai Institutes for biological {2.s,Chinese Academy of {2.s,shanghai 2.0032.china 2.department of Medicinal Chemistry,school of Pharmacy,Fudan University,shanghai 2.0032.china 3 State Key Laboratory of Genetic engineering & department of Microbiology,{12.,Fudan University,shanghai 2.0433,china 4 Laboratory of Disease and Health Genomics,Chinese National Human Genome Center at shanghai,shanghai 2.12.3,china Laboratory of Molecular Microbiology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China State Key Laboratory of Genetic engineering & department of Microbiology School of Life Science Fudan University Shanghai 200433 China Laboratory of Disease and Health Genomics Chinese National Human Genome Center at Shanghai Shanghai 201203 China

The genetic requirements for the transcription of glnA,encoding the major glutaminesynthetase in a rifamycin SV-producing Amycolatopsis mediterranei strain,U32.were *** experiments showed that the promoter of U32.glnA （pglnA） was likely to have two transcriptioninitiation sites:P1and P2.located 157 and 45 nucleotides （nt） upstream of the translational start codon,*** mobility shift and DNase I footprinting analyses revealed a 30 bp cis-element locatedat 45 to 75 nt downstream of P1,or 38 to 68 nt upstream of *** sequence of the cis-element displayedhigh similarity to the corresponding regions of pglnA from Streptomyces coelicolor and *** as a reporter gene,the expression levels of U32.pglnA and its deletion derivatives under differentnitrogen-source conditions were analyzed by detecting the catechol dioxygenase activities in ***54,*** J508 and *** FS10 （glnR mutant）.These in vivo studies showed that theactivation of U32.pglnA in *** required GlnR,and its binding to the U32.pglnA was furtherconfirmed by the gel mobility shift *** and heterologous expression of the U32.glnR allowed usto detect the in vitro interaction between the U32.GlnR and the corresponding pglnA *** shown by in vivo glnR inactivation and complementation indicated that GlnR is essential for theactive transcription of glnA in U32.

关键词： glnA promoter cis-element glnR Amycolatopsis mediterranei

Identification and Characterization of hmr19 Gene Encoding a Multidrug Resistance Efflux Protein from Streptomyces hygroscopicus *** Strain 10-2.

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 519-528页

作者： Lei QIN , Heng-An WANG1 , Zhong-Qin WU, Xiao-Feng ZHANG, Mei-Lei JIN,Zi-Xin DENG2. and Guo-Ping ZHAOshanghaiResearch Center of Biotechnology, shanghai Institute for {2. sciences, Chinese Academy of sciences,Graduate school of the Chinese Academy of sciences, shanghai 2.02.3, china 1school of Agriculture and Biology, shanghai Jiaotong University, shanghai 2.1101, china 2.13} and Biotechnology, shanghai Jiaotong University, shanghai 2.0030, china shanghaiResearch Center of Biotechnology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences school of Agriculture and Biology Shanghai Jiaotong University

The hmr19 gene was cloned from Streptomyces hygroscopicus subsp. yingchengensis strain 10- 2., a bacterium strain producing agricultural antibiotics. Sequence similarity comparison indicates that hmr19 gene may encode a predicted protein with 14 putative transmembrane α-helical spanners, belonging to the drug:H+ antiporter-2.family of the major facilitator superfamily. The expression of hmr19 in the mycelium of strain 10-2. was detected by Western blotting analysis. Gene replacement technology was employed to construct an hmr19 disruption mutant. The growth inhibition test against different antibiotics indicated that the mutant strain was 5–2. fold more susceptible to tetracycline, vancomycin and mitomycin C than the parental wild type strain. The mutant took up tetracycline much faster and accumulated more antibiotics than the wild type strain 10-2.. While with the addition of an energy uncoupler, carbonyl cyanide m- chlorophenylhydrazone, the characteristics of the accumulation of [3H]tetracycline in these two strains were almost the same. It was thus concluded that hmr19 encoded a multidrug resistance efflux protein.

关键词： multidrug resistance (MDR) gene replacement (knockout) Streptomyces Streptomyces hygroscopicus subsp. yingchengensis strain 10-2.

Mass spectrometry analysis of melanoma related O-glycans in sera

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science china Chemistry 2010年第4期53卷 807-811页

作者： BAI Chen1,4, WU Gang1 & ZHAO Liang2.3 1department of life {2., Fudan University, shanghai 2.0433, china 2.0} of Chemistry, Fudan University, shanghai 2.0433, china 3Institutes of Biomedical {2.s, Fudan University, shanghai 2.0433, china 4department of Food {2., shanghai Business school, shanghai 2.02.5, china 1. department of life {2. Fudan University Shanghai 200433 China4. Department of Food Science Shanghai Business School Shanghai 200235 China2. Department of Chemistry Fudan University Shanghai 200433 China3. Institutes of Biomedical Sciences Fudan University Shanghai 200433 China

Glycomics comparison was carried out by screening melanoma serum biomarkers between C57 mice with and without B16 implanted. O-glycans were released from 10 μL sera by β-elimination, purified by Graphitized Carbon Cartridge Solid Phase Extraction (GCC-SPE) and analyzed by MALDI-QIT-TOF-MS. MS raw data were acquired and exported by Launchpad software. MATLAB was then applied for further data analysis. 10 Glycans were considered to have stable changes after B16 implantation and 5 of them were under structural analysis via MS/MS.

关键词： mass spectrometry glycomics melanoma biomarkers

Boundary element-free method for elastodynamics

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 641-657页

作者： CHENG Yumin1 & PENG Miaojuan2.1. shanghai Institute of Applied Mathematics and Mechanics, shanghai University, shanghai 2.0072. china 2. department of Civil engineering, shanghai University, shanghai 2.0072. china 1. shanghai Institute of Applied Mathematics and Mechanics Shanghai University 200072 Shanghai China 2. department of Civil engineering Shanghai University 200072 Shanghai China

The moving least-square approximation is discussed first. Sometimes the method can form an ill-conditioned equation system, and thus the solution cannot be obtained correctly. A Hilbert space is presented on which an orthogonal function system mixed a weight function is defined. Next the improved moving least-square approximation is discussed in detail. The improved method has higher computational efficiency and precision than the old method, and cannot form an ill-conditioned equation system. A boundary element-free method (BEFM) for elastodynamics problems is presented by combining the boundary integral equation method for elastodynamics and the improved moving least-square approximation. The boundary element-free method is a meshless method of boundary integral equation and is a direct numerical method compared with others, in which the basic unknowns are the real solutions of the nodal variables and the boundary conditions can be applied easily. The boundary element-free method has a higher computational efficiency and precision. In addition, the numerical procedure of the boundary element-free method for elastodynamics problems is presented in this paper. Finally, some numerical examples are given.

关键词： moving least-square approximation, improved moving least-square approximation, elastodynamics, boundary integral equation, meshless method, boundary element-free method, Fourier eigen transform.

Impact chaos control and stress release——A key for development of ultra fine vibration milling

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Progress in Natural science:Materials International 2002年第5期12卷 18-23页

作者： WANG Shulin(department of Power engineering, University of {2. for science and Technology, {2. 2.0093, china) shanghai Univ Sci & Technol Dept Power Engn Shanghai 200093 Peoples R China

Through our previous experimental and analytical studies, it has been discovered that the key for the development of vibration milling is the impact chaos control and stress release. The necessities for the chaos control and stress release are: (i) to strictly e-liminate the sub-harmonics; (ii) to control the super-harmonics to a lower level and (iii) to load the system compressively with relatively higher period, in order that the vibration energy can be absorbed by the particles effectively and sufficiently. A new vibration model for ultra fine milling is proposed, which has wide applications in preparing ultra fine particles.

关键词： vibration mills ultra fine milling impact chaos control stress release.

Effect of Process Factors on Microstructure of Semisolid Continuous Casting Billets

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 242-245页

作者： Shuming Xing, Qijie Zhai, Hanqi Hu ( department of Mechanical engineering, Tsinghua University, Beijing 100084, {2. school of Material science and engineering, shanghai University, shanghai 2.0072. {2. Material science and engineering school, Univer department of Mechanical engineering Tsinghua University Beijing 100084 China school of Material science and {2. Shanghai University Shanghai 200072 China Material science and engineering {2. University of Science and Technology Beijing Beijing 100083 China

Semisolid continuous casting (SSCC) is a new technology to produce billets for semisolid metal forming (SSMF). The effect of process factors, such as pouring temperature, stirring rate, preheating temperature and thermal conductivity of stirring chamber, on the microstructure of SSCC billets was studied by means of the factorial experimental method. The results show that the microstructure of SSCC billets can be controlled by the above-mentioned four process factors. In order to obtain fine and rounded granular grains in an SSCC billet, the pouring temperature, preheating temperature and stirring rate should be kept in a moderate range, and the thermal conductivity of stirring chamber should be high. The regression equations with the process factors connecting the microstructure was also set up based on experimental data.

关键词： semisolid metal continuous casting process factors microstructure Metallurgy

Spatial continuity incorporated multi-attribute fuzzy clustering algorithm for blood vessels segmentation

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science china(Information sciences) 2010年第4期53卷 752-759页

作者： HAO JuTao1*, ZHAO JingJing2.& LI MingLu3 1school of Optical-Electrical and Computer engineering, University of {2. for science and Technology, {2. 2.0093, china 2.6} of Electrical engineering, {2. University of Electric Power, {2. 2.0090, china 3department of Computer science and engineering, {2. Jiaotong University, {2. 2.02.0, china 1. school of Optical-Electrical and Computer engineering University of Shanghai for Science and Technology Shanghai 200093 China2. Department of Electrical Engineering Shanghai University of Electric Power Shanghai 200090 China3. Department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

A three-dimensional representation of vasculature can be extremely important in image-guided neurosurgery, pre-surgical planning. In this paper, a spatial continuity incorporated multi-attribute fuzzy clustering algorithm (MAFCM S) is proposed to segment entire blood vessels from TOF MRA images. This clustering method takes both the intensity information and the geometrical information into account, while most of the cur- rent clustering methods only deal with the former. In this method, a new dissimilarity measure, which integrates the intensity and the geometry shape dissimilarity, is introduced. Because of the presence of the geometrical information, the new measure is able to differentiate the pixels with similar intensity values within different geometrical shape structures. Experimental results show that the new algorithm can get better segmentation.

关键词： fuzzy c-means clustering scale space analysis spatial continuity blood vessel segmentation multi-attribute fuzzy clustering

A simple solution route to control synthesis of Fe_3O_4 nanomaterials at low temperature and their magnetic properties

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science china Chemistry 2009年第7期52卷 916-923页

作者： LIU Yi1,2. CHEN Yun1, ZENG YuPing2.& WANG ShiLong3 1 department of Chemistry and Chemical engineering, Zaozhuang University, Zaozhuang 2.7160, {2. 2.shanghai Institute of Ceramics, Chinese Academy of sciences, shanghai 2.0050, {2. 3 school of life science and Technology, Tongji University, shanghai 2.0092. {2. 1. department of Chemistry and Chemical engineering Zaozhuang University Zaozhuang 277160 China 2. shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China 3. school of life science and Technology Tongji University Shanghai 200092 China

A series of nanostructured iron compounds including cubic Fe3O4 and orthorhombic FeOOH were synthesized via a facile low temperature (in the range of 60-100℃) solution method. In the whole process, the interaction between FeCl2.4H2. and methenamine (C6H12.4) was carried out through a reflux device under different reaction conditions such as temperature, solvent, and duration. The samples were detected by XRD, TEM, SAED, physical property measurement system, and Mssbauer spectroscopy, separately. The experiments showed that magnetic mixture nanoparticles had flake and rod morphologies, and cubic Fe3O4 took on grain nanostructure. Magnetism measurements indicated that the saturated magnetization of the as-obtained magnetic mixture was lower than that of the cubic magnetite. Mssbauer spectroscopy testified the sample consisting of cubic magnetite rather than γ-Fe2.3. In addition, a possible growth mechanism of cubic magnetic nanoparticles under different conditions was discussed.

关键词： magnetic nanoparticles cubic Fe3O4 oxidation-coprecipitation method reflux magnetic properties at room temperature Mssbauer spectrum

Virtual multi-dimensional internal bonds model and its application in simulation of rock mass

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science china(Technological sciences) 2008年第2期51卷 192-201页

作者： ZHANG ZhenNan1,2.& GE XiuRun3,4 1 department of Civil engineering,{2. University,{2. 2.0072.china 2.{2. Institute of Applied Mathematics and Mechanics,{2. University,{2. 2.0072. china 3 Institute of Geotechnical engineering,{2. Jiao Tong University,{2. 2.0030,china 4 Institute of Rock and Soil Mechanics,Chinese Academy of sciences,Wuhan 430071,china 1. department of Civil engineering Shanghai University Shanghai 200072 China 2. shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China 3. Institute of Geotechnical engineering Shanghai Jiao Tong University Shanghai 200030 China 4. Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China

VMIB (virtual multi-dimensional internal bonds) is a multiscale mechanical model developed from the VIB (virtual internal bond) theory. In VIB theory,the solid mate-rial is considered to consist of random-distributed material particles in microscale. These particles are connected with normal bonds. The macro constitutive relation is derived from the cohesive law between particles. However,in VMIB,the micro particles are connected with both normal and shear bonds. The macro constitutive relation is derived in terms of bond stiffness coefficients. It has been theoretically certified that there exists a corresponding relationship between the two bond stiffness coefficients and the two macro material constants,i.e. the Young’s modulus and Poisson ratio. This corresponding relationship suggests that it should be necessary and sufficient to simultaneously account for the normal and shear interactions between particles. Due to the fact that the fracture criterion is directly incorporated into the constitutive relation,both VIB and VMIB present many advantages in simulating fractures of materials. In the damage model of rock mass,a damage tensor is usually defined to describe the distribution of cracks. The damage value in one direction determines the relative stiffness of rock mass in this direction. In VMIB solid,the relative distribution density of micro bonds in one direction determines the relative macro stiffness of the material in this direction. The effects of the damage value and the relative distribution density of bonds are consistent. To simulate the failure behavior of rock mass with VMIB,the presented paper sets up a quantitative relationship between the damage tensor and the rela-tive distribution density of bonds. Comparison of the theoretical and the experi-mental results shows that VMIB model can represent the effect of distributed cracks on rock mass with this relationship. The presented work provides a founda-tion for further simulating fracture behavior

关键词： VMIB (virtual multi-dimensional internal bonds) rock mass VIB (virtual internal bonds) multi-cracked body numerical simulation