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Chinese Journal of Cancer Research 1998年第4期10卷 19-23页

作者：冼励坚刘宗潮潘启超李汉西 Cancer Center Cancer Institute Sun Yat-sen University of Medical Sciences Guangzhou 510060

Objective: To detect the effect of extract of Camellia Sinensis (ECS) and extract of Camellia Ptilophylla Chang (ECPC) on dna polymerase (Pol) of Ehrlich ascites tumor cells Methods: Referring to the method of K Ono, Pol was extracted from Ehrlich ascites tumor cells in mice Pol α, β, and γ were separated by phosphocellulose column chromatography and were identified The effect of ECPC and ECS on Pol was studied Results: ECPC and ECS were shown to inhibit the activity of Pol α, β, and γ IC 50 values of ECS on Pol α , β, and γ were 10 2μg/ml, 9 9μg/ml and 28 9μg/ml respectively IC 50 values of ECPC on Pol α, Pol β and Pol γ were 5 6μg/ml, 15μg/ml and 14 7μg/ml respectively The modes of inhibition of ECPC on Pol α, Pol β and Pol γ were noncompetitive with respect to template dna The Ki values of ECPC on Pol α , β, and γ were 2 68±0 12μg/ml, 2 24±0 12μg/ml , 2 56±0 18μg/ml Conclusion: ECPC and ECS were shown to have inhibitory effect on dna polymerase of tumor cells The mode of inhibition of ECPC on Pol α, Pol β and Pol γ were noncompetitive with respect to template dna

关键词： Extract of camellia sinensis Extract of camellia ptilophylla chang Inhibition Ehrlich ascites carcinoma dna polymerase

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OVEREXPRESSION OF Pfu dna polymerase BY RECOMBINANT BACULO VIRUS INFECTED SILKWORM

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OVEREXPRESSION OF Pfu DNA POLYMERASE BY RECOMBINANT BACULO V...

中国农业生物技术学会第三届会员代表大会暨学术交流会

作者： Yin Chen Xu’ai Lin Yinü Li Guifang Shen Zhifang Zhang (Biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081)

＜正＞The Pfu dna polymerase is a thermostable dna polymerase for high fidelity PCR from the hyperthermophilic archaeum Pyrococcus furiosus. It catalyzes the incorporation of nucleotides into duplex dna in the 5’-3’ direction in the presence of Mg2+ resulting in blunt-ended PCR products. Unlike Taq dna polymerase, Pfu dna polymerase exhibits 3’-5’ exonuclease activity （proofreading）, that enables the polymerase to correct mis-incorporation. Commercial available Pfu dna polymerases are purified form native or recombinant enzyme expressed in ***. In this study, the coding region of Pfu dna polymerase gene （PfuPol） was amplified from the genome of P. furiosus （strain JCM8422） using

关键词： Pyrococcus furiosus dna polymerase baculovirus silkworm

Expression and functional study of VpV262 Pol,a moderately halophilic dna polymerase from the Vibrio parahaemolyticus phage VpV262

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Expression and functional study of VpV262 Pol,a moderately h...

中国生物化学与分子生物学会2020全国学术在线会议

作者： Yaping Gao Yun He Igor Ivanov Xuerui Yang Hui Tian Xing Liu Research Center of Molecular Diagnostics and Sequencing Research Institute of Tsinghua University in Shenzhen MOE Key Lab of Bioinformatics School of Life SciencesTsinghua University

Halophilic organisms are found widely in environments where the salt concentration is higher than 0.2 *** proteins isolated from these organisms maintain structural integrity and function under high salt stress,whereas their non-halophilic homologs tend to aggregate and *** we report for the first time the expression and function of a dna polymerase(dnaPol) VpV262 Pol,which belongs to dnaPol Family A from Vibrio parahaemolyticus phage *** activity assay revealed that VpV262 Pol possessed 5’-3’ polymerase activity as well as 3’-5’ proofreading exonuclease ***262 Pol requires Mg or Mn to catalyze the polymerization *** activity assay under a wide range of salt concentrations showed that VpV262 Pol maintains the highest polymerase activity with 0-0.3 M of NaCl/KCl and0-0.5 M KAc(potassium acetate)/KGlc(potassium gluconate) when treated with 0-1 M corresponding salts,in contrast to significantly decreased activity of Phi29 Pol and Taq Pol above 0.2 *** with typical features of other halophilic proteins,negatively-charged amino acids are more frequently distributed on the surface of VpV262 Pol,contributing to highly solubility and enhanced *** 3 D-Structure of VpV262 Pol needs to be confirmed by experimental data further,this study here has added a member for the relatively small family of halotolerant dna polymerase,and provides a valuable reference in isolation and characterization of dna polymerases from halophilic organisms.

关键词： dna polymerase salt tolerance halophilic enzyme Vibrio parahaemolyticus phage VpV262 3D-Structure random coil

Biochemical Characterization of Translesion Synthesis by Sulfolobus acidocaldarius dna polymerases

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Chemical Research in Chinese Universities 2016年第2期32卷 226-233页

作者： PENG Li XIA Xu LIU Xipeng State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University Shanghai 200240 P R. China

To study the dna synthesis mechanism of Sulfolobus acidocaldarius, a thermophilic species from Crenarehaeota, two dna polymerases of B family（polB1 and polB3）, and one dna polymerase of Y family（polIV） were recombinantly expressed, purified and biochemically characterized. Both dna polymerases polBl（Saci_1537） and polB3（Saci_0074） possessed dna polymerase and 3＇ to 5＇ exonuclease activities; however, both the activities of B3 were very inefficient in vitro. The polIV（Saci_0554） was a polymerase, not an exonuclease. The activities of all the three dna polymerases were dependent on divalent metal ions Mn1＋ and Mg2＋. They showed the highest activity at pH values ranging from 8.0 to 9.5. Their activities were inhibited by KC1 with high concentration. The optimal reaction temperatures for the three dna polymerases were between 60 and 70 ℃. Deaminated bases dU and dI on dna template strongly hindered primer extension by the two dna polymerases of B family, not by the dna polymerase of Y family. dna polymerase of Y Family bypassed the two AP site analogues dSpacer and propane on template more easily than dna polymerases of B family. Our results suggest that the three dna polymerases coordinate to fulfill various dna synthesis in Sulfolobus acidocaldarius cell.

关键词： Archaeota Sulfolobus acidocaldarius dna polymerase dna damage dna replication

In Vitro Construction of Effective M1GS Ribozymes Targeting HCMV UL54 RNA Segments

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Acta Biochimica et Biophysica Sinica 2005年第3期37卷 210-214页

作者： Yun-Zhen SU Hong-Jian LI Yue-Qin LI Hao-Jun CHEN Dong-Sheng TANG Xin ZHANG Hong JIANG Tian-Hong ZHOU College of Life Science and Technology,Jinan University,Guangzhou 510632,China CollegeofLifeScienceandTechnology JinanUniversityGuangzhou510632China

Seven sequence-specific ribozymes(M1GS RNAs)derived in vitro from the catalytic RNAsubunit of Escherichia coli RNase P and targeting the mRNAs transcribed by the UL54 gene encoding thedna polymerase of human cytomegalovirus were screened from 11 ribozymes that were designed based onfour rules:(1)the NCCA-3′ terminal must be unpaired with the substrate;(2)the guide sequence(GS)mustbe at least 12 nt in length;(3)the eighth nucleotide must be U,counting from the site-1;and(4)around thecleavage site,the sites-1/+1/+2 must be U/G/C or C/G/*** investigation of the factors affecting thecleavage effect and the optimal ratio for M1GS/substrate was carried *** was determined that the optimalratio for M1GS/substrate was 2:1 and too much M1GS 1ed to substrate *** indicated *** M1GS that cleaved HCMV UL54 RNA segments in vitro were successfully designed and *** studies support the use of ribozyme M1GS as antisense molecules to silence HCMV mRNA in vitro,andusing the selection procedure as a general approach for the engineering of RNase P ribozymes.

关键词： ribonuclease P (RNase P) guide sequence HCMV dna polymerase

ENGINEERING dna polymeraseS FOR APPLICATION IN DNB-BASED SEQUENCING TECHNOLOGY

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ENGINEERING DNA POLYMERASES FOR APPLICATION IN DNB-BASED SEQ...

第十一届中国酶工程学术研讨会

作者：王林 Yue Zheng BGI Research Institute University of Copenhagen & BGI Research Institute Department of Biology University of Copenhagen & BGI Research Institute

dna polymerases serve as the core engine to afford sequence information in sequencing technologies that have revolutionized modern biological *** application in the DNB-based sequencing platform,an assemblage of dna polymerases was engineered to catalyze the requisite biochemical *** the process,naturally occurring polymerases were tapped into through deep-learning algorithms for constraints between individual protein residues to narrow down the protein sequence space and to annotate protein sequences in light of their catalytic *** the constraints were subsequently applied in designing potential polymerase candidates with the guidance of the sequence ***,ancestral protein sequences were estimated to expand the candidate ***,the candidates were subjected to in silico screening before examined by an HTS methodology based on fluorescence ***,the resulting proteins were expressed and purified for testing in the DNB-based sequencing *** sequencing data suggested that these proteins behave better than their existing counterparts.

关键词： dna nanoball(DNB) dna polymerase sequencing protein engineering high-throughput screening(HTS)

Nucleotide incorporation across from templating L-nucleoside by dna polymerases

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Nucleotide incorporation across from templating L-nucleoside...

中国化学会第30届学术年会-第二十八分会：化学生物学

作者： Li Wu Yating Xiao Qingju Liu Yujian He School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences

All natural nucleotides and the building blocks of dna chains possess *** polymerases are known to select preferably D-nucleotides over L-nucleotides during dna ***,we reported that several dna polymerases incorporated nucleotides across from L-thymidine in the dna *** of several dna polymerases was characterized and the results displayed that primer extension of 5’-3’natural nucleotides gets to end at chiral modification site with Taq and Phanta Max Super-Fidelity dna polymerase,but 5’-3’primer extension proceeds to the end of the template catalyzed by Deep Vent,Vent and Therminator dna ***,kinetics analyses of primer-extension showed that templating L-nucleosides significantly decreased the nucleotide incorporation rates catalyzed by Deep Vent dna polymerase or Vent dna polymerase comparing with normal template,and thus polymerase chain reactions were inhibited with the dna template containing consecutive *** addition,no single base mutation or mismatch mixture corresponding to the location of L-T in the template was found during dna synthesis when dna extension pass by L-nucleoside by dna *** data reported here offer ample functional grounds to explain why the L-nucleoside might be disfavored as a component of a coding system.

关键词： L-thymidine Primer extension dna polymerase Kinetics Mismatch

Rapid progress of dna replication studies in Archaea,the third domain of life

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Science China(Life Sciences) 2012年第5期55卷 386-403页

作者： ISHINO Yoshizumi ISHINO Sonoko Department of Bioscience and Biotechnology Graduate School of Bioresource and Bioenvironmental Sciences Kyushu University

Archaea,the third domain of life,are interesting organisms to study from the aspects of molecular and evolutionary *** cells have a unicellular ultrastructure without a nucleus,resembling bacterial cells,but the proteins involved in genetic information processing pathways,including dna replication,transcription,and translation,share strong similarities with those of ***,archaea provide useful model systems to understand the more complex mechanisms of genetic information processing in eukaryotic ***,the hyperthermophilic archaea provide very stable proteins,which are especially useful for the isolation of replisomal multicomplexes,to analyze their structures and *** review focuses on the history,current status,and future directions of archaeal dna replication studies.

关键词： Archaea dna replication dna polymerase replication fork replisome hyperthermophile

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经阴道超声诊断更年期子宫内膜增殖症

中国超声医学杂志 1999年第2期15卷 74-74页

作者：冯蕾云南省妇幼保健院

本文对１９９３年以来经阴道超声检查考虑为更年期内膜增殖症的病例做回顾性分析，目的在于总结更年期子宫内膜增殖症的较为可靠的声像图特征，为临床诊断提供一定的依据。本组共４８例，为妇科体检的受检者及门诊患者因主诉月经过多、... 详细信息

本文对１９９３年以来经阴道超声检查考虑为更年期内膜增殖症的病例做回顾性分析，目的在于总结更年期子宫内膜增殖症的较为可靠的声像图特征，为临床诊断提供一定的依据。本组共４８例，为妇科体检的受检者及门诊患者因主诉月经过多、经期延长或淋漓不尽、月经不规律、停...

关键词： Extract of camellia sinensis Extract of camellia ptilophylla chang Inhibition Ehrlich ascites carcinoma dna polymerase

损耗波生物传感器实时监控多聚酶dna的交互反应(英文)

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损耗波生物传感器实时监控多聚酶DNA的交互反应(英文)

“科技增强国力，青年开创未来——携手走向辉煌的新世纪”中国科协第三届青年学术年会

作者： Hing Leung Chan Department of Biology and Chemistry City University of Hong Kong

Recent advances in biosensor technology have contributed significantly to our understanding of the kinetic basis of molecular recognition *** enable real-time studies of biomolecular interactions without the need of ***, we have employed an optical biosensor based on evanescent wave detection to study the affinity and kinetics of the interactions between various dna polymerases and primer-template dna with perfectly matched or mismatched *** observed binding profiles are discussed to highlight the uniqueness of the biosensor technique in obtaining kinetic information of protein-dna interactions.

关键词： biosensor dna polymerase kinetics