检索结果-南通市图书馆

pH-Dependent Stability of EGX, A Multi-functional Cellulase from Mollusca, Ampullaria crossean

Acta Biochimica et Biophysica Sinica 2004年第9期36卷 603-608页

作者： Wen-Ying LI2, Ji WANG1, Yan-Hong LI1, Ming DING1, Gen-Jun XU1,3, Lan-Ying LIU2, and Fu-Kun ZHAO1,3* 1Key Laboratory of Proteomics, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, the Chinese Academy of sciences,Graduate School of the Chinese Academy of sciences, Shanghai 200031, china 2college of life science, Jilin university, Changchun 130023, china college of life science, zhejiang university of science and technology, hangzhou 310018, china college of life science Jilin UniversityChangchun 130023 China Key Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China college of life science Zhejiang University of Science and TechnologyHangzhou 310018 China

The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con- formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6–7.4. The activity of EGX remained about 80% in pH 5.6–7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3 M at pH 8.0. The α-helix at pH 5.4 was 40.51% in the absence of urea and 31.04% in the presence of 4 M urea. At pH 8.0 the α-helix was 7.23% in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions.

关键词： multi-functional cellulase stability Ampullaria crossean fluorescence spectroscopy pH-dependent structural change CD spectrum

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Expression and Identification of Mutated Osteoprotegerin in Culture Cells and Larvae of Silkworm

引用

Acta Biochimica et Biophysica Sinica 2004年第5期36卷 331-335页

作者： Hai-Long XIAO, Yong-Feng JIN, and Yao-Zhou ZHANG1* Institute of Biochemistry, college of life sciences, zhejiang university, hangzhou 310029, china college of life sciences, zhejiang university of science & technology, hangzhou 310018, china Institute of Biochemistry College of Life Sciences Zhejiang University Hangzhou 310029 China college of life sciences Zhejiang University of Science & Technology Hangzhou 310018 China

The mutated osteoprotegerin (OPG-372) gene was inserted into the baculovirus transfer vector pBacPAK8, and the recombinant plasmid was co-transfected with linearized Bm-BacPAK6 virus DNA into BmN cells, then homologous recombination occurred inside the cells. The recombinant virus BmNPV-OPG- 372 was screened and identified by Southern blotting. The recombinant human OPG-372 was expressed in cultured cells and the larvae of silkworm by inoculation of recombinant virus. The expression products were run on the SDS-PAGE and their immunoreactivities were determined by Western blotting. It was found that a 42 kD recombinant protein was expressed in BmN cells and a 46 kD one in larvae respectively. The bioactivi- ties of the recombinant proteins were determined by hypocalcemic effect assay in the mice. The results showed that the recombinant proteins had a significant hypocalcemic effect on mice sera.

关键词： OPG-372 silkworm baculovirus expression system hypocalcemic effect

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Accumulation of Pathogenesis-related Type-5 Like Proteins in Phytoplasma-infected Garland Chrysanthemum Chrysanthemum coronarium

引用

Acta Biochimica et Biophysica Sinica 2004年第11期36卷 773-779页

作者： Bo-Xiong ZHONG and Yan-Wei SHENDepartment of Bioresource science, college of Animal science, zhejiang university, hangzhou 310029, china Department of Bioresource science College of Animal Science Zhejiang UniversityHangzhou 310029 China

Soluble proteins extracted from leaves, apical shoots, axillary shoots, and stems of garland chrysanthemum plants infected by onion yellows phytoplasma were analyzed by two-dimensional gel electrophoresis. Computerized matching analysis revealed that at least six soluble proteins were accumulated specifically in phytoplasma-infected garland chrysanthemum. N-terminal amino acids sequences of these soluble

关键词： phytoplasma garland chrysanthemum Chrysanthemum coronarium pathogenesis-related proteins thaumatin osmotin

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Influences of Quinclorac on Culturable Microorganisms and Soil Respiration in Flooded Paddy Soil

引用

Biomedical and Environmental sciences 2003年第4期16卷 314-322页

作者： ZHEN-MEI LU, HANG MIN , AND YANG-FANG YE Institute of Microbiology, college of life science, zhejiang university, hangzhou 310029, zhejiang, china Institute of Microbiology College of Life Science Zhejiang University 浙江 Hangzhou 310029

Objective To investigate the potential effects of herbicide quinclorac (3,7-dichloro-8-quinoline-carboxylic) on the culturable microorganisms in flooded paddy soil. Methods Total soil aerobic bacteria, actinomycetes and fungi were counted by a 10-fold serial dilution plate technique. Numbers of anaerobic fermentative bacteria (AFB), denitrifying bacteria (DNB) and hydrogen-producing acetogenic bacteria (HPAB) were numerated by three-tube anaerobic most-probable-number (MPN) methods with anaerobic liquid enrichment media. The number of methanogenic bacteria (MB) and nitrogen-fixing bacteria (NFB) was determined by the rolling tube method in triplicate. Soil respiration was monitored by a 102G-type gas chromatography with a stainless steel column filled with GDX-104 and a thermal conductivity detector. Results Quinclorac concentration was an important factor affecting the populations of various culturable microorganisms. There were some significant differences in the aerobic heterotrophic bacteria. AFB and DNB between soils were supplemented with quinclorac and non-quinclorac at the early stage of incubation, but none of them was persistent. The number of fungi and DNB was increased in soil samples treated by lower than 1.33μg·g-1 dried soil, while the CFU of fungi and HPAB was inhibited in soil samples treated by higher than 1.33μg·g-1 dried soil. The population of actinomycete declined in negative proportion to the concentrations of quinclorac applied after 4 days. However, application of quinclorac greatly stimulated the growth of AFB and NFB. MB was more sensitive to quinclorac than the others, and the three soil samples with concentrations higher than 1 μg·g-1 dried soil declined significantly to less than 40% of that in the control, but the number of samples with lower concentrations of quinclorac was nearly equal to that in the control at the end of experiments. Conclusion Quinclorac is safe to the soil microorganisms when applied at normal concentrations (0.67

关键词： Quinclorac Soil culturable microorganisms Soil respiration Flooded paddy soil

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Use of the modified viral satellite DNA vector to silence mineral nutrition-related genes in plants: silencing of the tomato ferric chelate reductase gene, FRO1, as an example

引用

science china(life sciences) 2008年第5期51卷 402-409页

作者： HE XiuXia1,2,JIN ChongWei1, LI GuiXin3, YOU GuangYi4, ZHOU XuePing3 & ZHENG ShaoJian4 1 Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education, college of Environmental and Resource science, zhejiang university, hangzhou 310029, china 2 college of life science, Changchun university of science and technology, Changchun 130022, china 3 Institute of Biotechnology, zhejiang university, hangzhou 310029, china 4 State Key Laboratory of Plant Physiology and Biochemistry, college of life science, zhejiang university, hangzhou 310058, china Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education College of Environmental and Resource Science Zhejiang University Hangzhou China college of life science Changchun University of Science and Technology Changchun China Institute of Biotechnology Zhejiang University Hangzhou China State Key Laboratory of Plant Physiology and Biochemistry College of Life Science Zhejiang University Hangzhou China

Virus-induced gene silencing (VIGS) is potentially an attractive reverse-genetics tool for studies of plant gene function, but whether it is effective in silencing mineral nutritional-related genes in roots has not been demonstrated. Here we report on an efficient VIGS system that functions in tomato roots using a modified viral satellite DNA (DNAmβ) associated with Tomato yellow leaf curl china virus (TYLCCNV). A cDNA fragment of the ferric chelate reductase gene (FRO1) from tomato was inserted into the DNAmβ vector. Tomato roots agro-inoculated with DNAmβ carrying both a fragment of FRO1 and TYLCCNV used as a helper virus exhibited a significant reduction at the FRO1 mRNA level. As a consequence, ferric chelate reductase activity, as determined by visualization of the pink FeBPDS3 complex was significantly decreased. Our results clearly demonstrated that VIGS system can be employed to investigate gene function associated with plant nutrient uptake in roots.

关键词： virus-induced gene silencing roots ferric chelate reductase

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Postnatal Developmental Expression of Calbindin,Calretinin and Parvalbumin in Mouse Main Olfactory Bulb

引用

Acta Biochimica et Biophysica Sinica 2005年第4期37卷 276-282页

作者： Zhao-Ping QIN Shu-Ming YE Ji-Zeng DU Gong-Yu SHEN Department of Biology,college of life science,zhejiang university,hangzhou 310027,china Department of Biology College of Life Science Zhejiang UniversityHangzhou 310027 China

The distribution of calbindin,calretinin and parvalbumin during the development of the mousemain olfactory bulb （MOB） was studied using immunohistochemistry *** results are as follows:（1）calbindin-immunoreactive profiles were mainly located in the glomerular layer,and few large calbindin-immunoreactive cells were found in the subependymal layer of postnatal day 10 （P10） to postnatal day 40（P40） mice;（2） no calbindin was detected in the mitral cell layer at any stage;（3） calretinin-immunoreactiveprofiles were present in all layers of the main olfactory bulb at all stages,especially in the olfactory nervelayer,glomerular layer and granule cell layer;（4）parvalbumin-immunoreactive profiles were mainly locatedin the external plexiform layer （except for P10 mice）;（5）weakly stained parvalbumin-immunoreactive pro-files were present in the glomerular layer at all stages;and （6） no parvalbumin was detected in the mitral celllayer at any stage.

关键词： calbindin calretinin parvalbumin mouse main olfactory bulb

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Group sparse representation for image categorization and semantic video retrieval

引用

science china(Information sciences) 2011年第10期54卷 2051-2063页

作者： LIU YaNan 1,2 ,WU Fei 2 & ZHUANG YueTing 2 1 School of Information,zhejiang university of Finance & Economics,hangzhou,310018,china 2 college of Computer science and technology,zhejiang university,hangzhou,310012,china School of Information Zhejiang University of Finance & Economics Hangzhou China college of Computer science and technology Zhejiang University Hangzhou China

Multimedia content analysis and management are a promising and challenging *** this paper we develop a novel approach to image representation,which we call group sparse representation (GSR),for image classification and video *** basic idea is to represent a test image as a weighted combination of all the training *** particular,we introduce two sets of weight coefficients,one for each training image and the other for each ***,we formulate our concern as a group nonnegative garrote *** resulting representations are sparse,and they are appropriate for discriminant *** on Caltech101 and PASCAL VOC2008 image dataset and TRECVID2005 video corpus testify that our proposed approach is efficient and effective.

关键词： compressive sensing group sparse representation bag-of-SIFT-words nonnegative garrote l1-minimization apcluster

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Immobilized chitosan as a selective absorbent for the nickel removal in water sample

引用

Journal of Environmental sciences 2003年第5期15卷 633-638页

作者： WU Jian min, WANG Yong yao (Department of Chemistry, college of science, zhejiang university, hangzhou 310027, china. ) Department of Chemistry College of Science Zhejiang University Hangzhou 310029

Method for preparation of chitosan immobilized on silica gel(CTS silica) was described. The CTS silica was used as absorbent for the absorption of nickel in water. The results showed that this absorbent had relatively high selectivity and strong affinity to nickel. The maximum absorption capacity for nickel can reach 667 mg/g of chitosan. Factors that affect the absorption capacity, such as pH, ion strength and the presence of calcium, EDTA and the mechanism of absorption were discussed in detail. The absorbent can be regenerated with acid and reused for several times. The recovery rate for nickel can reach 99 99%. This absorbent filled in a column can be used in nickel removal from wastewater and drinking water.

关键词： immobilized chitosan nickel wastewater treatment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

L_p-mixed intersection bodies

引用

science china Mathematics 2008年第12期51卷 2172-2188页

作者： ZHAO ChangJian Department of Information and Mathematics sciences, college of science, china Jiliang university, hangzhou 310018, china Department of Information and Mathematics sciences College of Science China Jiliang University Hangzhou China

In this paper the author first introduce a new concept of Lp-dual mixed volumes of star bodies which extends the classical dual mixed volumes. Moreover, we extend the notions of Lp- intersection body to Lp-mixed intersection body. Inequalities for Lp-dual mixed volumes of Lp-mixed intersection bodies are established and the results established here provide new estimates for these type of inequalities.

关键词： L p -dual mixed volumes L p -intersection bodies L p -mixed intersection bodies 52A40

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi

引用

Journal of Environmental sciences 2009年第5期21卷 691-695页

作者： ZHENG Rongquan, LI Canyang college of Chemistry and life science, zhejiang Normal university, Jinhua 321004, china. college of Chemistry and life science Zhejiang Normal University Jinhua 321004 China

To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guiUelmi for 7 and 14 d were 4285＋339 mg/kg and 3207＋248 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2800 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction.

关键词： lead Pheretima guillelmi sperm morphology locomotion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：