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Properties and nucleotide sequence of linear plasmid-like DNA pC4 from mitochondria of Cucumis sativus

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Chinese Science Bulletin 2001年第15期46卷 1288-1291页

作者： Junying Li Yingda Wen Yanling Bai Juan Fu Xiuming Zhang Caichang Gao Nankai Univ Inst Mol Biol Tianjin 300071 Peoples R China

Four kinds of mitochondrial plasmid-like dnas, designated pC1, pC2, pC3 and pC4, were detected in Cucumis sativus Jinyan No. 4. The electron microscopy observation showed that pC4 was linear conformation. Complete sequence of pC4 was cloned into pUC19 with E. coli JM109 as host. Sequence analysis revealed that pC4 was 370 bp long, the shortest one among all the reported mitochondrial plasmid-like dnas. pC4 was AT rich. It contained terminal direct repeat sequence (35 bp in length)as well as many short direct and inverted repeats. ORFs in pC4 were short. pC4 was found to be homologous to nuclear dnas, but lack homology with main mitochondrial and chloroplast dnas. pC4-homologous sequence also occurred in nuclear genome of Jinyan No. 7 which contained no mitochondrial plasmid-like dnas. The hybridization pattern of Jinyan No. 7 was slightly different from that of Jinyan No. 4. This suggested that pC4 occurred at the forepart of Cucumis sativus species divergence and integrated into the nuclear genome,

关键词： Cucumis sativus linear mitochondrial plasmid-like dnas nucleotide sequence homology.

Molecular Characterization on the Early Developmental Stages of the Egyptian Toad <i>Bufo regularis</i>Reuss

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Open Journal of Genetics 2014年第5期4卷 343-354页

作者： Alaa El-Din H. Sayed Afaf I. Elballouz Ekbal T. Wassif Zoology Department Faculty of Science Assiut University Assiut Egypt Zoology Department Faculty of Science Assiut University Assiut Egypt Zoology Department Faculty of Science Misurate University Misurate Libya

The present study aimed to investigate changes in the protein contents using SDS-PAGE, also using the random amplified polymorphic DNA (RAPD-PCR) assay to identify changes in DNA concentration in the embryos of Egyptian toad Bufo regularis. Our experiment started when tadpoles began to feed. The adapted embryos were divided into 3 large tanks of 200 embryos each, collections of samples started from feeding age every three days. Cluster method was used to indicate the distinct distance between the band patterns of different stages. An increase occurred in the concentration of protein fractions in these tadpoles upon metamorphosis and that when metamorphosis was completed. DNA concentration exhibited an evident low values at the premetamorphic stage 44 (105.85 ± 0.519 ng/μl) compared with the other more advanced developmental stages 55 and 56 (204.056 ± 0.651 ng/μl and 234.55 ± 2.325 ng/μl respectively). In conclusion, acquire information about the changes in the molecular content of Bufo regularis during metamorphosis has been estimated.

关键词： Genes Bufo regularis Protein dnas

Genotypic Analysis, Construction of the Expression System and Immunological Identification of the Recombinant Proteins of the LipL32 Gene in the Dominant Serogroups of Leptospira interrogans in China

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Journal of Microbiology and Immunology 2004年第1期2卷 17-23页

作者：范兴丽严杰毛亚飞李立伟李淑萍 Zhejiang Medical College Department of Medical Microbiology and Parasitology College of Medical Science Zhejiang University

To investigate the existence of the major outer membrane protein (MOMP) gene LipL32 in 15 dominant Chinese strains of 15 serogroups of Leptospira interrogans and 2 international strains of 2 serogroups of Leptospira biflexa, and to clone and construct the expression system as well as to identify the recombinant proteins, genomic dnas from strains of leptospira were prepared by routine phenol-chloroform method, and the fragments of the LipL32 gene with the whole length from the strains were amplified with high fidelity PCR. The target amplification products were sequenced after T-A cloning, and the expression system for the genes were thereby constructed. Expression of the recombinant proteins was identified by using SDS-PAGE after induction with IPTG at different dosages. Western blot assays with rabbit antiserum against the whole cell of TR/PatocⅠ of Leptospira and immunized serum with rMOMPs were used to determine the immunoreactivity and immunogenicity of the recombinant proteins. Microscopic agglutination test was used to determine the cross- agglutination titres in rabbit sera immunized with rMOMPs, and the cell adherence model of Leptospira was used to examine the blocking effects of rabbit antisera against these rMOMPs. It was found that the LipL32 gene could be found in all the 17 strains of Leptospira mentioned above with two different genotypes, i.e. LipL32/1 and LipL32/2. Amounts of expressions of rMOMP1 and rMOMP2 after IPTG accounted for 40% and 10% of the total bacterial proteins respectively. Both rMOMP1 and rMOMP2 could combine with the rabbit antiserum against leptospiral TR/PatocⅠ, and could induce the production of agglutination antibodies to these 17 strains of Leptospira with 1∶2 to 1∶64 MAT titres. The rabbit anti-rMOMP1 and anti-MOMP2 antibodies at 1∶2 to 1∶16 dilutions could efficiently block adherence of Leptospira. It concludes that all the Leptospira tested in the present study possess LipL32/1 or LipL32/2 genes, and the constructed expression system can express the rMOMP1 and rMOMP2. T

关键词：遗传型分解作用表达系统免疫学辨别方法重组蛋白质 LipL32基因基因分型显性作用血清中国 dnas 问号钩端螺旋体

苏云金芽孢杆菌伴孢晶体中20-kb dnas上染色体基因的鉴定

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湖南师范大学自然科学学报 2007年第4期30卷 114-118页

作者：孙运军袁志明夏立秋魏薇付祖姣黄璠丁学知胡胜标中国科学院武汉病毒研究所中国武汉430071 湖南师范大学生命科学学院微生物分子生物学湖南省重点实验室中国长沙410081

已有的研究表明苏云金芽孢杆菌(Bacillus thuringiensis,Bt)4.0718菌株菱形晶体中含有与原毒素紧密结合的20-kb dnas,利用PCR-RFLP分析发现在这些20-kb dnas上含有cry1Aa、cry1Ac、cry2Aa和cry2Ab基因.本研究利用特异引物从4.0718菌株中20-kb dnas上分别扩增出带有自身调控序列的cry1Ac和cry2Aa基因,并将其分别电转至Bt无晶体菌株Cry-B中获得重组菌株Cry-B(pHC42)和Cry-B(pHC39).SDS-PAGE和透射电镜分析表明这两种重组菌株能够分别产生由130-kDa的Cry1Ac原毒素形成的菱形晶体以及由65-kDa的Cry2Aa原毒素形成的方形晶体.毒力生测的结果显示,这两种菌株的表达产物对棉铃虫(Helicoverpa armigera)幼虫具有预期的杀虫效果.重组菌株分别形成的两种晶体经不同的缓冲液溶解后能释放出与20-kb dnas紧密结合的原毒素,同时在20-kb dnas上均可检测到源于Bt染色体的spo0A和nprA基因片段.

关键词：苏云金芽孢杆菌伴孢晶体 20-kb dnas 染色体

Torque and Topology of Braided dnas under Tension

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医用生物力学 2019年第A1期34卷 173-173页

作者： Yang Liu Sumitabha Brahmachari Ke Ding Huiling Bai Bo Tan John FMarko Botao Xiao School of Biology and Biological Engineering South China University of TechnologyGuangzhou510006China Department of Physics and Astronomy Northwestern UniversityEvanston IL60208USA School of Physics Huazhong University of Science and TechnologyWuhan430074China Department of Molecular Biosciences Northwestern UniversityEvanston IL60208

Double helix dnas become intertwined around one another during replication and recombination.Here we used magnetic tweezers to make braided DNA molecules and measured their torques under various catenations(Ca)at forces ranging from 0.3 to 8 pN.Images of braided DNA constructs under tensions were captured by scanning electron microscopy which showed major and minor grooves of dnas and plectonemes of the braids.When the two DNA molecules were braided,the extension decreased as the catenation increased from 0 to 50 turns.We used a thermodynamic Maxwell relation to deduce the torque by integrating the change in the braid extension as a function of the force.The torque increased with the catenation,force and intertether distance until the catenation reached a buckling point.Under the condition of 2 pN force and Ca=20,the torque was computed to be 31,21 and 15 pN nm for the braids of which the intertether distances were 54%,31%and 26%of the DNA contour length,respectively.At an 8.03 pN holding force,the torque was computed to be 76 pN nm as the catenation increased from 0 to 30 turns,or as the catenation density varied from 0 to 0.053.The torque reached a plateau when the catenation increased above 20,indicating formation of braid-plectonemes.The twist modulus increased with the catenation prior to reaching a peak.Before reaching the peak,the moduli were higher than those of a single twisted DNA under the same catenation and applied force.Our experimental data agrees well with the calculation results by a recently developed semiflexible polymer model.Our measurements of the nonlinear torque of the braid establish new fundamental properties of DNA intertwining,which is key to understanding DNA replication and gene expression.The speaker will also introduce briefly other projects in the Xiao group including direct measurements of theforce spectrum of single unlabeled proteins such as adhesive nano-fibers for biofilm,the screening of integrin-targeted peptides drugs by single cell approaches,and the micromechanical appro

关键词： DNA Torque and Topology of Braided dnas under Tension

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基于组件式GIS配电网技术

电工技术 2006年第7期 17-19页

作者：张锦爱刘前进杨城回华南理工大学电力学院广东510640 中水东北勘测设计研究有限责任公司长春130021

根据电力配网和地理信息系统(GIS)的特征,本文采用组件式GIS和配电管理系统(DMS)技术相结合探讨了配电网技术,着重讨论了配网分析系统(dnas),具体阐述了dnas系统中各个组件的功能,指出了该系统对实现电力资源的优化配置和配电网发展的... 详细信息

根据电力配网和地理信息系统(GIS)的特征,本文采用组件式GIS和配电管理系统(DMS)技术相结合探讨了配电网技术,着重讨论了配网分析系统(dnas),具体阐述了dnas系统中各个组件的功能,指出了该系统对实现电力资源的优化配置和配电网发展的重要意义。

关键词：组件式GIS DMS dnas

基于IEC 61968规范的DMS系统设计

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基于IEC 61968规范的DMS系统设计

2003中国电机工程学会电力系统自动化专委会供用电管理...

作者：赵凤青夏寨芳烟台东方电子信息产业股份有限公司

随着 DMS(Distributed Management System)系统的功能不断发展,外延不断扩大,传统的由一个特定提供商提供 DMS 所有功能的实现模式变的越来越不现实,用户迫切希望 DMS 不同的应用子系统,特别是不同厂商的应用子系统能以某种规范的方式... 详细信息

随着 DMS(Distributed Management System)系统的功能不断发展,外延不断扩大,传统的由一个特定提供商提供 DMS 所有功能的实现模式变的越来越不现实,用户迫切希望 DMS 不同的应用子系统,特别是不同厂商的应用子系统能以某种规范的方式方便地集成在一起.实现不同应用间的数据交换和共享、减少数据维护工作量、降低 DMS 系统建设的总成本。在这种背景下,IEC 提出了 IEC61968标准用于规范 DMS 应用功能的集成。本文将对 IEC 61968规范进行简单的介绍,探讨遵循 IEC 61968规范的 DMS 功能设计、网络建模和子系统接口设计方法。

关键词： DMS IEC 61968 IRM DIEM IEC 61970 CIM SCADA dnas AM/FM/GIS

来源： cnki会议评论

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大肠癌形态测定分析及其临床意义

中华病理学杂志 1990年第1期19卷 61-63页

作者：周未工王燕玲等北京医科大学人民医院外科肿瘤研究室 100034 北京医科大学人民医院外科肿瘤研究室 1

应用形态测定技术，对80例大肠癌进行DNA含量（DNAP）及其标准差（dnas、细胞核面积标准差（NAS）、核浆比（NCR0和癌胚抗原含量（CEAD）5个参数的定量测定。其中DNAP、NAS、NCR和CEAD大肠癌患者的预后。提出：DNAP和NCR较高的患者可能... 详细信息

应用形态测定技术，对80例大肠癌进行DNA含量（DNAP）及其标准差（dnas、细胞核面积标准差（NAS）、核浆比（NCR0和癌胚抗原含量（CEAD）5个参数的定量测定。其中DNAP、NAS、NCR和CEAD大肠癌患者的预后。提出：DNAP和NCR较高的患者可能预后不良，加强对此类患者的治疗和随访，有可能提高大肠癌患者的5年生存率。

关键词：大肠肿瘤预后影象处理计算机辅助技术 NAS DNA DNAP dnas NAS NCR CEAD

由限制性片段长度多态性和随机放大多态dnas鉴定出优良高粱系的遗传

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园艺与种苗 1995年第2期 58-58页

９５２０６由限制性片段长度多态性和随机放大多态ＤＮＡｓ鉴定出优良高粱系的遗传多样性──（Ｒ．Ａ．Ｖｉｅｒｌｉｎｇ等），ＴｈｅｏｒｅｔｉｃａｌａｎｄＡｐｐｌｉｅｄＧｅｎｅｔｉ－ｃｓ．１９９４．Ｖｏｌ．８７，Ｎｏ，７，８... 详细信息

９５２０６由限制性片段长度多态性和随机放大多态ＤＮＡｓ鉴定出优良高粱系的遗传多样性──（Ｒ．Ａ．Ｖｉｅｒｌｉｎｇ等），ＴｈｅｏｒｅｔｉｃａｌａｎｄＡｐｐｌｉｅｄＧｅｎｅｔｉ－ｃｓ．１９９４．Ｖｏｌ．８７，Ｎｏ，７，８１６～８２０（英文）本研究的目的是...

关键词：高粱限制性片段长度多态性 dnas