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非解朊栖热菌HG102.热β-糖苷酶的结构与功能研究

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生物工程学报 2005年第1期21卷 84-91页

作者：杨雪鹏杨寿钧韩北忠金城中国科学院微生物研究所微生物资源前期开发国家重点实验室北京100080 中国农业大学食品科学与营养工程学院北京100083

非解朊栖热菌HG10 2.热 β_糖苷酶为 (β α) 8桶状结构 ,是具有水解功能和转糖苷功能的单体酶。该酶可以作为一个很好的模型来研究糖苷酶的反应机制、底物特异性和耐热的分子基础。根据对该酶的晶体结构解析和同家族酶的结构比较 ,推... 详细信息

非解朊栖热菌HG10 2.热 β_糖苷酶为 (β α) 8桶状结构 ,是具有水解功能和转糖苷功能的单体酶。该酶可以作为一个很好的模型来研究糖苷酶的反应机制、底物特异性和耐热的分子基础。根据对该酶的晶体结构解析和同家族酶的结构比较 ,推测Glu16 4和Glu338分别是质子供体和亲核基团两个活性位点 ;在α_螺旋N端第一位的脯氨酸和蛋白质外周的精氨酸是耐热机制的关键位点和关键氨基酸残基。为确定这些氨基酸残基的功能 ,通过基因定点突变的方法分别把Glu16 4、Glu338、Pro316、Pro35 6、Pro344和Arg32.5置换成Gln、Ala、Gly、Ala、Phe和Leu ,同时还对Pro316和Pro35 6进行了双置换。突变酶经过纯化得到电泳纯 ,用CD光谱进行了野生酶和突变酶的结构比较。通过突变酶的酶功能和酶学性质分析 ,结果表明Glu16 4和Glu338分别是质子供体和亲核基团 ,亲核基团的突变酶TnglyE338A可以合成混合型糖苷键寡糖类似物 ;在α_螺旋N端第一位的Pro316和Pro35 6以及在蛋白质外周形成离子键的Arg32.5均是对耐热性有贡献的关键氨基酸残基。

关键词： β-糖苷酶转糖苷活性热稳定性定点突变

Overexpression of a tobacco small G protein gene NtRop1 causes salt sensitivity and hydrogen peroxide production in transgenic plants

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Science China(life sciences) 2008年第5期51卷 383-390页

作者： CAO YangRong1,2. LI ZhiGang1,2. CHEN Tao1,2. ZHANG ZhiGang1, ZHANG JinSong1 & CHEN ShouYi1 1 National Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of sciences, Beijing 100101, China 2.Graduate School of Chinese Academy of sciences, Beijing 100039, China National Key Lab of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China

The small GTPases of Rop/Rho family is central regulators of important cellular processes in plants. Tobacco small G protein gene NtRop1 has been isolated; however, its roles in stress responses were unknown. In the present study, the genomic sequence of NtRop1 was cloned, which has seven exons and six introns, similar to the Rop gene structure from Arabidopsis. The NtRop1 gene was constitutively expressed in the different organs whereas the other six Rop genes from tobacco had differential expression patterns. The expression of the NtRop1 gene was moderately induced by methyl viologen, NaCl, and ACC treatments, but slightly inhibited by ABA treatment, with no significant induction by NAA treatment. The transgenic Arabidopsis plants overexpressing the NtRop1 showed increased salt sensitivity as can be seen from the reduced root growth and elevated relative electrolyte leakage. The hydrogen peroxide production was also promoted in the NtRop1-trangenic plants in comparison with wild type plants. These results imply that the NtRop1 may confer salt sensitivity through activation of H2.2.production during plant response to salt stress.

关键词： small G protein NtRop1 salt sensitive hydrogen peroxide

Characterization of mitochondrial genome of Chinese wild mulberry silkworm, Bomyx mandarina(Lepidoptera:Bombycidae)

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Science China(life sciences) 2008年第8期51卷 693-701页

作者： PAN MinHui1, YU QuanYou1, XIA YuLing1, DAI FangYin1, LIU YanQun2. LU Cheng1, ZHANG Ze1 & XIANG ZhongHuai1 1 Key Sericultural Laboratory of Agricultural Ministry, Southwest University, Chongqing 400716, China 2.college of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110161, China Key Sericultural Laboratory of Agricultural Ministry Southwest University Chongqing China college of Bioscience and Biotechnology Shenyang Agricultural University Shenyang China

The complete mitochondrial genome of Chinese Bombyx mandarina(ChBm) was *** cir-cular genome is 15682.bp long, and contains a typical gene complement, order, and arrangement iden-tical to that of Bombyx mori(***) and Japanese Bombyx mandarina(JaBm) except for two addi-tional tRNA-like structures:tRNASer(TGA)-like and tRNAIle(TAT)-*** protein-coding sequences are initi-ated with a typical ATN codon except for the COI gene, which has a 4-bp TTAG putative initiator *** of 13 protein-coding genes(PCGs) have a complete termination codon(all TAA), but the re-maining two genes terminate with incomplete *** tRNAs have the typical clover-leaf structures of mitochondrial tRNAs, with the exception of tRNASer(TGA)-like, with a four stem-and-loop *** length of the A+T-rich region of ChBm is 484 bp, shorter than those of JaBm(747 bp) and ***(494―499 bp).Phylogenetic analysis among ***, ChBm, JaBm, and Antheraea pernyi(Anpe) showed that *** is more closely related to ChBm than *** earliest divergence time estimate for ***-ChBm and ***-JaBm is about 1.08±0.18―1.41±0.2. and 1.53±0.2.―2.01±0.2. Mya, *** and JaBm diverged around 1.11±0.16―1.45±0.2. Mya.

关键词： Chinese Bombyx mandarina mtDNA phylogeny origin of Bombyx mori

A pear 1-Aminocyclopropane-1-Carboxylate synthase gene preferentially expressed in leaves

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A pear 1-Aminocyclopropane-1-Carboxylate synthase gene prefe...

Investigation of the stability of 2.-CE interface

第十三届全国植物基因组学大会

作者： Haiyan Shi~(1*),Yuxing Zhang~1,Liang Chen~(1,2.3) 1 college of Horticulture,Agricultural University of Hebei,Baoding 71001,China 2.Wuhan Botanical Garden,Chinese Academy of sciences,Wuhan 430074,China 3 Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture,Chinese Academy of sciences,Wuhan 430074,China

In this study,a cDNA clone encoding putative ACC synthase,PpACSI,were isolated from a cDNA library produced using mRNA from pear(Pyrus pyrifolia).The cDNA clone,designated PpACS1(GenBank accession ***2.4383),comprised...

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Investigation of the stability of 2D-CE interface

Heterodimerization and function analysis of human apelin receptor and kappa opioid receptor

30th International Symposium on Capillary Chromatography、4th GC×GC Symposium、16th National Symposium and Exhibition on Chromatography,i.e. 1st Dalian International Symposium and Exhibition on Chromatography

作者： Huiyan You~(1 2. Jianping Qi~1 Fan Liu~1 Lihua Zhang~2.Weibing Zhang~2.Yukui Zhang~(2.) 1.Environmental and Chemical Engineering college Dalian University Dalian 11662. China 2.National Chromatography R.&A.Center Dalian Institute of Chemical Physics The Chinese Academy of sciences Dalian11602. China

＜正＞Along with science development,we need to separate more and more *** separation methods are *** electrophoresis（CE）and capillary electrochromatography（CEC）methods have already been developed,besides the traditional gas chromatography（GC）and liquid chromatography（LC）.Separation modes have already developed from one dimension to *** present,researchers are paying more and more attention to the two dimension（2.）*** plays an important role for biological samples *** design and stability of the interface is very important in two dimension *** has become the bottleneck of this technique and has not made a *** research is still in primary stage.

关键词： 2.-CE Interface High voltage

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Heterodimerization and function analysis of human apelin rec...

中药金叶败毒制剂抗人巨细胞病毒感染的作用机制

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： Ya-Lin LI~1 Bo BAI~(2.*) Jing CHEN~2.Hui DU~1 1 Department of Neurobiology Taishan Medical college Taian 2.1000 China 2.Department of Neurobiology Jining Medical college Taian 2.2.00 China

＜正＞Objective Increasing evidence suggests that G protein-coupled receptors（GPCRs） form functional dimers or larger oligomeric complexes through homo- or heterodimerization,affecting their functional *** receptor and kappa opioid receptor are both GPCRs superfamily *** previous studies by co-immunoprecipitation showed that the two GPCRs could form *** study used bioluminescence resonance energy transfer（BRET） to confirm the formation of heterodimer in living cells and analyze the function of the *** Molecular cloning technique was used to construct expressing vectors of apelin and kappa opioid receptors,then both vectors were cotransfected into human embryonic kidney（HEK-2.3） cells,and then immunofluorescence double labeling and bioluminescence resonance energy transfer（BRET） were used to detect *** blotting and radioimmunoassay were used to detect whether the signal transduction pathway could be changed by *** Plasmids hApelin-R-eGFP and hRluc-KOR-pcDNA3.1 were successfully constructed,and the plasmids were successfully transfected or cotransfected into HEK-2.3 cells Confocal microscopy results showed that apelin receptor and kappa opioid receptor are both expressed in the cell membrane,and the distribution of hApelin-R-eGFP and hRluc-KOR-pcDNA3.1 are with highly consistency,which indicates that they have potential compacity to form ***-2.3 cells were cotransfected with hRluc-KOR-pcDNA3.1 and hApelin-R-eGFP,then the heterodimerization were proved by *** these results showed that apelin receptor and kappa opioid receptor could form *** apelin-13 stimulation, cAMP level produced by apelin receptor and kappa opioid receptor coexpressed HEK-2.3 cells were significantly decreased than apelin receptor expressed HEK-2.3 *** p44/42.APK（ERK1/2.）level in cotransfected HEK2.3 cell was significantly higher than apelin receptor expressed HEK-2.3 c

关键词： apelin receptor kappa opioid receptor heterodimerization signal transduction

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华中科技大学学报（医学版） 2005年第3期34卷 345-347,352页

作者：袁慧刘世新闻良珍李丹华中科技大学同济医学院附属同济医院妇产科武汉430030 华中科技大学同济医学院法医系武汉430030

目的探讨中药金叶败毒制剂抗人巨细胞病毒(HCMV)感染的作用机制。方法用HCMVAD169感染人胚肺成纤维细胞,采用MTT法观察细胞的增殖活性,应用半定量RTPCR方法检测中药金叶败毒制剂和更昔洛韦(GCV)干预后感染细胞cyclinD1mRNA及细胞周期素... 详细信息

目的探讨中药金叶败毒制剂抗人巨细胞病毒(HCMV)感染的作用机制。方法用HCMVAD169感染人胚肺成纤维细胞,采用MTT法观察细胞的增殖活性,应用半定量RTPCR方法检测中药金叶败毒制剂和更昔洛韦(GCV)干预后感染细胞cyclinD1mRNA及细胞周期素依赖激酶4(CDK4)mRNA的表达水平。结果金叶败毒制剂和更昔洛韦能明显提高HCMV感染细胞cyclinD1及CDK4的表达,诱导G0/G1期细胞进入S和G2.M期,从而促进宿主细胞增殖。结论金叶败毒制剂可能通过促进HCMV感染细胞cyclinD1及CDK4的表达,促进宿主细胞增殖而发挥抗病毒作用。

关键词：金叶败毒制剂巨细胞病毒细胞周期素D1 细胞周期素依赖激酶4 细胞增殖

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人胸腺肽β4基因的克隆表达及活性检测

生物化学与生物物理学报 2002年第4期34卷 502-505页

作者：陈妍柯杨辉路凡蒲勤李仁德赵忠良兰州大学生命科学学院第四军医大学生物化学与分子生物学教研室第四军医大学生物化学与分子生物学教研室兰州730000 西安710032

采用化学与酶促合成技术 ,将胸腺肽 β4基因拆分为两个末端互补的片段进行化学合成 ,经变性、退火以及T4DNA聚合酶延伸过程 ,获得完整编码的基因片段。通过一平一粘末端连接 ,将胸腺肽 β4基因片段克隆入pLDH4 (一种大肠杆菌温度诱导表... 详细信息

采用化学与酶促合成技术 ,将胸腺肽 β4基因拆分为两个末端互补的片段进行化学合成 ,经变性、退火以及T4DNA聚合酶延伸过程 ,获得完整编码的基因片段。通过一平一粘末端连接 ,将胸腺肽 β4基因片段克隆入pLDH4 (一种大肠杆菌温度诱导表达载体 )的EcoRV和HindIII位点之间。经克隆筛选和DNA序列测定 ,获得目的基因表达工程菌 ,且表达量占细菌总蛋白质的 30 %。利用盐析和多种层析技术联合纯化该表达多肽 ,纯度达95 % ;活性测定表明纯化的人胸腺肽 β4能够促进淋巴细胞的增殖和分化

关键词：人胸腺肽β4 基因表达 E玫瑰花结 MTT

Density isomer of nuclear matter in an equivalent mass approach

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Nuclear Science and Techniques 2013年第5期24卷 24-30页

作者： GAO Li 2.U Zhenyan PENG Guangxiong college of Physics University of Chinese Academy of Sciences Department of Physics Shandong University of Technology Theoretical Physics Center for Science Facilities Institute of High Energy Physics

The equation of state of symmetric nuclear matter is studied with an equivalent mass *** equivalent mass of a nucleon has been expanded to order 4 in *** first determine the first-order expansion coefficient in the quantum hadron dynamics,then calculate the coefficients of the second to fourth order for the given binding energy and incompressibility at the normal nuclear saturation *** is found that there appears a density isomeric state if the incompressibility is smaller than a critical *** model dependence of the conclusion has also been checked by varying the first-order coefficient.

关键词：核物质状态方程饱和密度质量方针异构体等效量子强子动力学质量模型膨胀系数