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Elementary study of differential expression of total soluble proteins in different life phases of Porphyra yezoensis
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作者 孟春晓 高政权 +2 位作者 王依涛 罗韬 叶乃好 《Marine Science Bulletin》 CAS 2010年第2期32-37,共6页
Total soluble proteins of different life stages, filamentous sporophytes cultivated in high temperatures, and blade gametophytes harvested in different seasons, were identified by SDS-PAGE. The types and amounts of ex... Total soluble proteins of different life stages, filamentous sporophytes cultivated in high temperatures, and blade gametophytes harvested in different seasons, were identified by SDS-PAGE. The types and amounts of expressed proteins also varied amongst the samples. The fewest soluble proteins were present in filamentous sporophytes. There were more types and amounts of soluble protein in conchospores than in filamentous sporophytes, but fewer than in bulgy sporophytes. More types of protein were detected in filamentous sporophytes cultivated in high temperatures than in those growing in normal situations. The most types and amounts of protein were found in blade gametophytes in all samples. Blade gametophytes harvested last year and stored at -20 ℃ showed only minor differences in expression of proteins when compared with those harvested in different seasons. 展开更多
关键词 Porphyra yezoensis total soluble proteins differential expression
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Soluble expression of recomb inant cMyc,Klf4,Oct4,and Sox2 proteins in bacteria and transduction into living cells 被引量:5
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作者 Guo-Dan Liu Shi-Feng Zhou +4 位作者 Xu-Chen Ding Chun-Lai Fang Shu-Yong Mi Xiang-Chun Gao Qing Han 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期560-566,共7页
AIM:To develop a new method to produce recombinant reprogramming proteins,c Myc,Klf4,Oct4,and Sox2,in soluble format with low cost for the generation of induced pluripotent stem cells(i PSCs).METHODS:A short polyp... AIM:To develop a new method to produce recombinant reprogramming proteins,c Myc,Klf4,Oct4,and Sox2,in soluble format with low cost for the generation of induced pluripotent stem cells(i PSCs).METHODS:A short polypeptide sequence derived from the HIV trans-activator of transcription protein(TAT) and the nucleus localization signal(NLS) polypeptide were fused to the N terminus of the reprogramming proteins and they were constructed into p Cold-SUMO vector which can extremely improve the solubility of recombinant proteins.Then these vector plasmids were transformed into E.coli BL21(DE3) Chaperone competent cells for amplification.The solubility of these recombinant proteins was determined by SDS-PAGE and Coomassie brilliant blue staining.The recombinant proteins were purified by NiNTA resin and identified by Western blot.The transduction of these proteins into HEK 293 T cells were evaluated by immunofluorescence staining.RESULTS:These four reprogramming proteins could be produced in soluble format in p Cold-SUMO expression vector system with the assistance of chaperone proteins in bacteria.The proteins were purified successfully with a purity of over 70% with a relative high transduction rate into 293 cells.CONCLUSION:The results in the present study indicate the four important reprogramming proteins,c Myc,Klf4,Oct4,and Sox2,can be produced in soluble format in bacteria with low cost.Our new method thus might be expected to greatly contribute to the future study of i PSCs. 展开更多
关键词 reprogramming proteins induced pluripotent stem cells soluble expression protein transduction
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Gene Sequence, Soluble Expression and Homologous Comparison of a D-Hydantoinase fromPseudomonas putida YZ-26 被引量:3
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作者 SHI Ya-wei ZHAO Li-xia +2 位作者 NIU Li-xi FENG Xia YUAN Jing-ming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第5期552-557,共6页
A 1440bp open-reading frame encoding D-hydantoinase from Pseudomonas putida YZ-26 was cloned and sequenced( GenBank AY387829). The DNA fragment was inserted into Nde and BamHI sites of vector pET-3a, yielding a reco... A 1440bp open-reading frame encoding D-hydantoinase from Pseudomonas putida YZ-26 was cloned and sequenced( GenBank AY387829). The DNA fragment was inserted into Nde and BamHI sites of vector pET-3a, yielding a recombinant plasmid, pET-HDT. After being transferred into the host strain, the artificial strain, pET-HDT/ E. coli BL21 can express the D-hydantoinase as the soluble form in the Lura-Bertani medium without addition of any inducers. The activity of the enzyme toward substrate DL-hydantoin can reach 3000-4000 IU per cells from one-liter bacterial culture incubated at 30 ℃ for 10-12 h. By the comparison of amino acid sequence homology, hydrophobic residues analysis and secondary structure prediction, it was found that D-hydantoinase reported herein is quite similar to that from Pseudomonas putdia CCRC12857, and alike to that from Pseudomonas putdia DSM84 or other bacteria. A rapid and efficient purification procedure of the enzyme was performed by a three-step procedure: ammonium sulfate fractionation, phenyl Sepharose hydrophobic interaction chromatography and Sephacryl S-200 gel filtration. The molecular mass of the monomeric enzyme is 52042 Da as determined by MALDI-TOF mass spectrometry. 展开更多
关键词 D-HYDANTOINASE Gene sequence soluble expression Homologous comparison PURIFICATION Mass spectrum
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Chemical Chaperones Increasing Expression Level of Soluble Single-chain Fv Antibody(scFv2F3) 被引量:2
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作者 DU Xiu-bo SUN Ye +6 位作者 LIN Feng ZHENG Ke-yan WANG Ke-wei LIN Ting-ting LIU Jun-qiu SHEN jia-cong LUO Gui-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第1期69-75,共7页
Glutathione peroxidase(GPX) is a sclenoenzyme that protects the biomembrane and other cellular components against oxidative damage. The selenium-containing single chain Fv fragment of monoelonal antibody 2173 (Se s... Glutathione peroxidase(GPX) is a sclenoenzyme that protects the biomembrane and other cellular components against oxidative damage. The selenium-containing single chain Fv fragment of monoelonal antibody 2173 (Se scFv2F3) is a kind of GPX mimic and it has a wide clinical applications because of its high activity and low antigenicity. Se-seFv2F3 is generated by the chemical modification of the single chain Fv fragment of monoelonal antibody 2F3 ( scFv2F3 ), which can be expressed in E. coll. In this article, the effect of chemical chaperones, such as glycerol, glucose, and β-cyclodextrin added to the culture medium, on the expression of soluble scFv2F3 was investigated. The expression level was evaluated by the determination of soluble scFv2F3 contents in the whole cell lysates. The results suggest that both glycerol and β-cyclodextrin greatly increase the expression level of soluble scFv2F3, and β-cyclodextrin is found to be more effective compared with glycerol. Glucose has a slight effect on the expression level of soluble scFv2F3. This is the first example, wherein β-cyclodextrin has been used as a chemical chaperone during the cell culture to improve the expression level of recombinant proteins. In addition, chemical chaperones are found to decrease the toxic effect of IPTG on cells. 展开更多
关键词 Glutathione peroxidase soluble expression GLYCEROL GLUCOSE Β-CYCLODEXTRIN
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Soluble Expression,Purification and Characterization of Single-chain Fv Catalytic Antibody(sFv-2F3) 被引量:2
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作者 SUNYe LIWei-jia +4 位作者 MAJi-sheng MUYing DUXiu-bo YANGang-lin LUOGui-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期317-322,共6页
To find optimal conditions for expressing the soluble form of sFv-2F3 and to study the purification and property of its derivative Se-sFv-2F3,the preferred expression conditions were investigated by means of orthogona... To find optimal conditions for expressing the soluble form of sFv-2F3 and to study the purification and property of its derivative Se-sFv-2F3,the preferred expression conditions were investigated by means of orthogonal design. These culture conditions included incubation temperature,inducer concentration, induction time and cell concentration. The evaluation of expression was accomplished by the analysis of whole cell lysates and the yield of soluble sFv-2F3 was calculated according to the analysis of Profinder(FTI-500,Pharmacia). The purification procedure was carried out via a two-step purification procedure consisting of ion-exchange chromatography,followed by immobilized metal affinity chromatography(IMAC). The antioxidant efficacy of Se-sFv-2F3 was demonstrated by the determination of the content of the main product of lipid peroxidation,MDA,the viability of cells and the activity of LDH. We obtained the preferred culture conditions to grow the engineered bacteria and the procedure for preparing soluble sFv-2F3 and confirmed the antioxidant efficacy of Se-sFv-2F3. 展开更多
关键词 Se-sFv-2F3 soluble expression Glutathione peroxidase ANTIOXIDANT
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Efficient and Soluble Expression of α Protein of Clostridium perfringens and Preparation of Genetic Engineering Subunit Vaccine
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作者 Sun Yu Yang Lin +6 位作者 Wang Chuanbin Dong Hao Qu Ping Zhao Bolin Hu Dongmei Yang Tianyi Song Xiaohui 《Animal Husbandry and Feed Science》 CAS 2017年第5期284-288,305,共6页
[Objective] The paper was to develop genetic engineering vaccine that can express α exotoxin antigen protein efficiently without destroying its immunogenicity for preventing and controlling the diseases caused by Clo... [Objective] The paper was to develop genetic engineering vaccine that can express α exotoxin antigen protein efficiently without destroying its immunogenicity for preventing and controlling the diseases caused by Clostridium perfringens. [Method] Efficiently expressed soluble recombinant α protein was obtained from Escherichia coli expression system by optimizing codon,removing signal peptide,selecting sequences with better hydrophilicity and antigenicity,and optimizing expression conditions. [Result] Mice obtained higher serum antibody level when immunized by α protein,and the immune protection rates against type A,type B,type C and type D C. perfringens were 100%,90%,85% and 90%,respectively. The antibody titer of mice within 7-14 d after the third immunization reached the peak. [Conclusion]The α protein has good immunogenicity,and can be further used to develop genetic engineering subunit vaccines for preventing C. perfringens. 展开更多
关键词 CLOSTRIDIUM perfringens α PROTEIN soluble expression and PURIFICATION Genetic engineering SUBUNIT VACCINE
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Cloning and Expression of the cDNA of a Murine Soluble Fas
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作者 胡中波 邹萍 +3 位作者 李爱香 肖娟 仲照东 刘凌波 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第3期186-189,196,共5页
In order to regulate the apoptosis induced by Fas FasL system, a soluble isoform of mouse Fas was cloned from thymocytes of immature mice with the primers designed according to the full length Fas cDNA sequence in t... In order to regulate the apoptosis induced by Fas FasL system, a soluble isoform of mouse Fas was cloned from thymocytes of immature mice with the primers designed according to the full length Fas cDNA sequence in the GeneBank. It was directionally inserted into the intermedium vector pUC19. DNA sequencing proved that it was consistent with the expected sequence. Then it was subcloned into the eukaryotic expression vector pCA13, which was used to construct the recombinant vector pCA13 FasC. By lipofectamine (LF2000) mediated transfection, pCA13 FasC was transfected into the 293 cells. RT PCR and Western blot indicated that the murine soluble Fas C protein was expressed in the 293 cells. Apoptosis inducing test showed that the expression of this murine Fas C could block the Fas induced apoptosis, which confirmed the biological activity of the recombinant Fas C. 展开更多
关键词 soluble Fas MOUSE eukaryotic expression
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Efficient and Soluble Expression of N Protein of Peste Des Petits Ruminants Virus and Development of Indirect ELISA
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作者 Sun Yu Zhao Bolin +7 位作者 Wang Xiaoying Dong Hao Zhai Xinyan Qu Ping Hu Dongmei Yang Tianyi Shi Hui Song Xiaohui 《Animal Husbandry and Feed Science》 CAS 2017年第1期15-18,共4页
[ Objective] The paper was to get effective soluble N protein to establish indirect ELISA method for Peste des petits ruminants (PPR). [ Method] Soluble N protein with high expression was obtained from Escherichia c... [ Objective] The paper was to get effective soluble N protein to establish indirect ELISA method for Peste des petits ruminants (PPR). [ Method] Soluble N protein with high expression was obtained from Escherichia coli expression system through codon optimization and optimization of expression conditions, and indirect ELISA detection method based on N protein was further established. [ Result] The assay had no cross reaction with other sheep pathogens. The intra- and inter-batch variation coefficients were less than 9%, indicating the method had good repeatability. Furthermore, totally 480 clinical serum samples were detec- ted by the assay, and the agreement rate with commercial ELISA kit (IDVET) was 98.33%. [ Conclusion] The study laid a foundation for further development of mature PPRV antibody detection kits. 展开更多
关键词 Pestedes petits ruminants N active protein soluble expression and purification Indirect ELISA
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Eukaryotic expression, purification and activity characterization of human soluble DSG2 extracellular domain protein
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作者 CHEN Nan LI Xiao-yue +6 位作者 GU Xin-yu WU Tong-xin ZHANG Ru LI Yun TANG Xiang-ping DAI Jin YI Yong-xiang 《Journal of Hainan Medical University》 CAS 2023年第10期1-7,共7页
Objective:To construct a secretory eukaryotic expression vector of DSG2 fused with the Fc region of the human IgG,to validate its expression in 293T cells,and to purify the secretory protein with biological activity.M... Objective:To construct a secretory eukaryotic expression vector of DSG2 fused with the Fc region of the human IgG,to validate its expression in 293T cells,and to purify the secretory protein with biological activity.Methods:The DSG2 extracellular domain fragment gene(DSG2ex),was amplified by PCR,and was inserted into the eukaryotic expression plasmid pCMV3-IgG1 to construct the recombinant eukaryotic expression plasmid-pCMV3-DSG2ex-IgG1.The successfully constructed eukaryotic expression plasmid was transfected into 293T cells to express and secrete DSG2 extracellular domain protein.The targeted protein was purified from the cell culture supernatant by Protein A affinity chromatography and confirmed by Western Blotting and ELISA.Results:The pCMV3-DSG2ex-IgG1 eukaryotic expression plasmid was successfully constructed.The highest protein expression level was obtained with 293T cells after 96 h of transfection.The relative molecular mass of the purified product was between 100 and 130 kDa was estimated by SDS-PAGE,which was consistent with the expectation.The yield of the purified protein reached 0.8 mg/ml with a purity over 90%.The purified DSG2 extracellular domain protein with IgG1 tag was recognized by IgG monoclonal antibodies by Western blotting.Moreover,the ELISA results showed that the prepared DSG2 extracellular domain protein had significant binding activity to human type 55 adenovirus Fiber Knob protein(HAdV-55).Conclusion:A simple and efficient method for eukaryotic expression and purification of human soluble DSG2 extracellular domain protein was successfully established,and biologically active DSG2 extracellular domain protein was purified,which laid the foundation for the later study of its protein function and anti-adenovirus drugs. 展开更多
关键词 Human soluble DSG2 extracellular domain protein Eukaryotic expression PURIFICATION Activity characterization
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High-level expression and purification of Plutella xylostella acetylcholinesterase in Pichia pastoris and its potential application 被引量:2
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作者 LIU Niu CHE Jun +2 位作者 LAI Duo WEN Jin-jun XU Han-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第6期1358-1366,共9页
The acetylcholinesterase 2(AChE2)cloned from Plutella xylostella was first successfully expressed in methylotrophic yeast Pichia pastoris GS115.One transformant with high-level expression of the recombinant AChE(rA... The acetylcholinesterase 2(AChE2)cloned from Plutella xylostella was first successfully expressed in methylotrophic yeast Pichia pastoris GS115.One transformant with high-level expression of the recombinant AChE(rAChE,23.2 U mL-1in supernatant)was selected by plating on increasing concentrations of antibiotic G418 and by using a simple and specific chromogenic reaction with indoxyl acetate as a substrate.The maximum production of r ACh E reached about 11.8 mg of the enzyme protein per liter of culture.The r ACh E was first precipitated with ammonium sulfate(50%saturation)and then purified with procainamide affinity column chromatography.The enzyme was purified 12.1-fold with a yield of 22.8%and a high specific activity of 448.3 U mg-1.It was sensitive to inhibition by methamidophos and pirimicarb,the calculated 50% inhibitory concentration(IC50)values of the two pesticides were 0.357 and 0.888 mg L-1,respectively,and the calculated 70% inhibitory concentration(IC70)values were 0.521 and 0.839 mg L-1,respectively.The results suggested that it has a potential application in the detection of pesticide residues. 展开更多
关键词 Plutella xylostella ACETYLCHOLINESTERASE Pichia pastoris high-level expression
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Primary Purification of Co-expressed Soluble and Insoluble Alpha-interferon 2b from Recombinant E. coli
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作者 徐志南 岑沛霖 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第6期686-689,共4页
Alpha-interferon 2b (IFN 2b) was produced both in soluble and insoluble forms from recombinant E. coli. The dissolution of the expressed IFN 2b in inclusion body was carried out and it was found that the optimal condi... Alpha-interferon 2b (IFN 2b) was produced both in soluble and insoluble forms from recombinant E. coli. The dissolution of the expressed IFN 2b in inclusion body was carried out and it was found that the optimal condition to dissolve the expressed protein was 7 mol稬1guanidinium salt solution at pH 3.0. The resultant solution was diluted 20 times using pH 6.0 buffer to refold the protein correctly. The cation exchange column was employed to purify both refolded and soluble IFN 2b. For soluble IFN sample, high IFN 2b recovery yield (92.1%) with 91.7% purity was obtained in the eluate. However, for refolded IFN sample, only 72.7% of IFN 2b was recovered with relatively low purity (56.8%) by cation exchange chromatography. Although the expression level of insoluble IFN was higher than that of co-expressed soluble IFN in this recombinant E. coli cells, the productivity of bioactive IFN 2b was higher with soluble expressed IFN after primary purification process. Soluble expression of foreign proteins in recombinant bacteria might be an alternative strategy for efficient production of heterogeneous pro-teins due to high bioactivity and simple downstream protein purification process. 展开更多
关键词 alpha-interferon 2b soluble expression inclusion body REFOLDING purification *
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Construction of Lactuca sativa Plastid Transformation Vector and High-level Expression of gfp Gene in Escherichia coli
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作者 Siming HOU Liying ZHOU +4 位作者 Lulu BU Chunlei YANG Ting GAO Tian TIAN Zheng'an YANG 《Agricultural Biotechnology》 CAS 2016年第4期1-4,共4页
Using genomic DNA of bolting-tolerant lettuce as a template,flanking fragments of lettuce plastid rpo A gene were amplified and cloned by PCR. Targeting the sites of these two fragments,homologous recombinant fragment... Using genomic DNA of bolting-tolerant lettuce as a template,flanking fragments of lettuce plastid rpo A gene were amplified and cloned by PCR. Targeting the sites of these two fragments,homologous recombinant fragments of exogenous gene were integrated to construct lettuce plastid expression vector p Brpo AGFP,which harbored the expression cassette Prrn-gfp-aad A-Tpsb A. The results showed that the amplified flanking fragments were 1.2 and 1.1 kb in size. After sequencing,restriction digestion,ligation and transformation,lettuce plastid expression vector containing expression cassette Prrn-gfp-aad A-Tpsb A was constructed and confirmed by SDS-PAGE electrophoresis. The results of SDS-PAGE electrophoresis indicated that gfp gene was efficiently expressed under the regulation of plasmid specific promoter Prrn and terminator Tpsb A. GFP accounted for 45. 6% of total soluble proteins; inclusion bodies accounted for 47.5 % of bacterial proteins,which reached relatively high expression levels. The construction of lettuce plastid expression vector p Brpo A-GFP laid a solid foundation for establishment of subsequent lettuce plastid transformation system and genetic improvement of lettuce using various functional genes. 展开更多
关键词 Lactuca sativa var. capitata L. PLASTID expression vector gfp gene high-level expression
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TANDEM REPEATING OF THE EXPRESSIONCARTRIDGE──A NOVEL STRATEGY TOENHANCE THE EXPRESSION EFFICIENCY OFCLONED GENE IN ESCHERICHIA COLI
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作者 林缨 卢圣栋 《Chinese Medical Sciences Journal》 CAS CSCD 1996年第4期204-208,共5页
A novel strategy to enhance the expression efficiency of cloned target gene in Escherichia coli was developed. The whole expression cartridge , consisting of promoter. SD sequence , target gene and transcription termi... A novel strategy to enhance the expression efficiency of cloned target gene in Escherichia coli was developed. The whole expression cartridge , consisting of promoter. SD sequence , target gene and transcription terminator, was tandem repeatedly engineered into a expression plasmid. Consequently, the copy number of specific gene was increased substantially, leading to the improvement of expression efficiency.Using this approach, a recombinant plasmid , designed as PLYD, was constructed and transformated into the Escherichia coli strain DH5α. Upon induction , the desired protein was synthesized in a considerable level and accumulated up to 63% of the total cell proteins. The present study revealed that tandem repeating of expression cartridge provided a convenient means to improve expression level efficiently. 展开更多
关键词 expression cartridge tandem repeating: high-level expression copy number
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Expression,purification and identification of LBD domain of human PPARδ in E.coli
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作者 Liu Hua Li Changqing +1 位作者 Ling Baodong Zhou Qinxin 《Journal of Medical Colleges of PLA(China)》 CAS 2009年第2期76-83,共8页
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors known to play a pivotal role in regulations of metabolism. In order to yield soluble ligand binding domain of PPARδ (P... Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors known to play a pivotal role in regulations of metabolism. In order to yield soluble ligand binding domain of PPARδ (PPARδLBD) for screening ligands, the cDNA was amplified using total RNA from HepG2 cells by RT-PCR. Then the enzyme-digested product was inserted . downstream of the malE gene in the vectorpMAL-p2x, which encoded maltose-binding protein (MBP), resulting in the expression of an MBP-PPARδLBD fusion protein. The recombinant plasmid was transformed into E. coli TBI that was cultured shakily at 30 ℃, 200 r/min and induced by 0.4 mmol/L IPTG for 6 h. The cells were harvested by centrifugation and broken by sonication. The expressed fusion protein was soluble and accounted for 0.31 of the total protein in the supernatant. Western blot analysis showed that the expressed MBP-PPARδLBD could bind to anti-MBP-antibody. The MBP-PPARδLBD fusion protein of 77 kDa and the PPARδLBD protein of 34 kDa were obtained by amylose-resin affinity chromatography without or with digestion of Factor Xa. They were both homogeneity, judged by SDS-PAGE. The recombinant MBP-PPARδLBD and PPARδLBD protein with high purity is obtained, which provides the necessary material for screening and researching PPARδ ligands. 展开更多
关键词 PPAδLBD Maltose-binding protein soluble expression PURIFICATION Affinity chromatography
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High-level soluble expression of the hemA gene from Rhodobacter capsulatus and comparative study of its enzymatic properties 被引量:4
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作者 Jia-wei LOU Li ZHU +3 位作者 Mian-bin WU Li-rong YANG Jian-ping LIN Pei-lin CEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2014年第5期491-499,共9页
The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS), was expressed in Escherichia coil Rosetta (DE3) and the enzymatic properties of the purified recombinant ALAS (RC-ALAS) ... The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS), was expressed in Escherichia coil Rosetta (DE3) and the enzymatic properties of the purified recombinant ALAS (RC-ALAS) were studied. Compared with ALASs encoded by hemA genes from Agrobacterium radiobacter(AR-ALAS) and Rhodobacter sphaeroides (RS-ALAS), the specific activity of RC-ALAS reached 198.2 U/mg, which was about 31.2% and 69.5% higher than those of AR-ALAS (151.1 U/mg) and RS-ALAS (116.9 U/mg), respectively. The optimum pH values and temperatures of the three above mentioned enzymes were all pH 7.5 and 37 ℃, respectively. Moreover, RC-ALAS was more sensitive to pH, while the other two were sensitive to temperature. The effects of metals, ethylene diamine tetraacetic acid (EDTA), and sodium dodecyl sulfate (SDS) on the three ALASs were also investigated. The results indicate that they had the same effects on the activities of the three ALASs. SDS and metal ions such as Co^2+, Zn^2+, and Cu^2+ strongly inhibited the activities of the ALASs, while Mn^2+ exerted slight inhibition, and K^+, Ca^2+, Ba^2+, Mg^2+, or EDTA had no significant effect. The specificity constant of succinyl coenzyme A [(kcatlKm)^S-CoA] of RC-ALAS was 1.4989, which was higher than those of AR-ALAS (0.7456) and RS-ALAS (1.1699), showing its high catalytic efficiency. The fed-batch fermentation was conducted using the recombinant strain containing the R. capsulatus hemA gene, and the yield of 5-aminolevulinic acid (ALA) achieved was 8.8 g/L (67 mmol/L) under the appropriate conditions. 展开更多
关键词 5-Aminolevulinic acid Rhodobacter capsulatus high-level expression Enzymatic properties
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DsbA-DsbAmut fusion chaperon improved soluble expression of human trypsinogen-1 in Escherichia coli 被引量:2
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作者 Ye Liu Wenyong Zhang +3 位作者 Xubin Yang Guangbo Kang Damei Wang He Huang 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2015年第4期511-521,共11页
A co-expressing system ofDsbA-DsbAmut was suggested for the first time to enhance the soluble expression of human trypsin-1. As a control, leaderless DsbA chaperone was also co-expressed with human trypsin-1. Vectors ... A co-expressing system ofDsbA-DsbAmut was suggested for the first time to enhance the soluble expression of human trypsin-1. As a control, leaderless DsbA chaperone was also co-expressed with human trypsin-1. Vectors pET39b-trypsin and pET28a-DsbA- DsbAn^ut-trypsin with the above two DsbA fusion tag were constructed. The strain with vector pET39b-trypsin expressed fusion protein DsbA-trypsin in form of inclusion bodies. While in E. coli BL21 (DE3) strain with vector pET28a-DsbA-DsbAmUt-trypsin, the soluble expression of trypsin fusion protein was achieved. Under the optimized expression conditions, the soluble fraction accounted for about 49.43% of total DsbA-DsbAmUt-trypsin proteins in crude supernatant. The purification yield was 4.15% by nickel chelating chromatography and 3.3 mg activated trypsin with a purity of 88.68% was obtained from 1 L LB broth. To detect the possible functions of DsbA series chaperons in trypsin fusion protein, we analyzed the primary three-dimensional structure of fusion proteins, mainly focusing on the compatibleness between trypsin and fusion chaperons. The results suggested that (1) besides the primary function in periplasm, leaderless DsbA or DsbAmut may also act as a signal sequences-like leader targeted to periplasm that partly relieved the pressure from fusion protein overexpression and inclusion body formation, and (2) as there was significant soluble expression of DsbA-DsbAmUt-trypsin compared with DsbA-trypsin, DsbArout may function as charge or hydrophobic balance in recombinant protein DsbA-DsbAmut- trypsin. 展开更多
关键词 DSBA DsbA-DsbAmut soluble expression trypsin CHAPERON
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The production of Strains Highly Expressing Human Interleukin-2 cDNA
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作者 张大军 冯博 皇甫永穆 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1994年第1期16-19,共4页
The plasmid pTLIL-2,which only directed a low-level expression of human interleukin 2(IL-2) cDNA in E.coli,was reconstructed:a series of deletions were made in 3'non-coding region of human IL-2 cDNA,and 7 recombin... The plasmid pTLIL-2,which only directed a low-level expression of human interleukin 2(IL-2) cDNA in E.coli,was reconstructed:a series of deletions were made in 3'non-coding region of human IL-2 cDNA,and 7 recombinant plasmids with different deletions were selected,on the other hand, a Tac promoter sequence from pDR540 was inserted to upstream of IL-2 cDNA in pTLIL-2 so that pTLIL-2DT,which contains double Tac promoters,was constructed.And then,E.coli JM103 was transformed with the above 8 recombinant plasmids respectively.The expression efficiency of IL-2 cDNA in E.cbli transformed with different plasmids was evaluated by means of SDS-PAGE and measuring 3H-TdR incorporation of IL-2-dependent activated T lymphocytes in the presence of bacterial extracts.Three engineering strains with high efficiency of IL-2 expression were selected,and all of these strains could produce recombinant IL-2(rIL-2)4 times more than E.coil JM103/pTLIL-2. 展开更多
关键词 INTERLEUKIN-2 high-level expression genetic engineering
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枸杞SWEET基因家族鉴定及其与可溶性糖含量关系
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作者 尹跃 秦小雅 +3 位作者 赵建华 杨萍 何军 安巍 《西北植物学报》 CAS CSCD 北大核心 2024年第3期396-407,共12页
【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。... 【目的】糖外排转运蛋白(sugars will eventually be exported transporters,SWEETs)在植物生长发育过程中发挥重要作用,解析SWEETs基因在枸杞果实发育过程中对糖积累作用,为进一步揭示SWEETs基因在枸杞果实发育过程中的作用提供参考。【方法】用生物信息学方法对枸杞SWEET基因(LbaSWEETs)进行全基因组鉴定,并用已发表的转录数据分析LbaSWEETs在果实发育时期的基因表达情况。【结果】枸杞SWEET基因家族共有37个成员,随机分布于10条染色体上,分别编码152~621个氨基酸,蛋白质分子质量为16.87~69.97 kD,等电点为4.96~9.86。亚细胞定位预测位于叶绿体或质膜,大多数含有7个跨膜螺旋。系统进化分析发现,37个LbaSWEETs蛋白可分为4个亚群,每个亚群的基因结构和保守基序组成相似。启动子元件分析表明:Lba-SWEETs基因启动子富含大量激素响应、逆境胁迫和生长发育响应元件。转录组数据和qRT-PCR分析表明:LbaSWEET9和LbaSWEET29基因表达量随果实成熟呈现显著增加。相关性分析结果表明,LbaSWEET9和LbaSWEET29基因表达量与果糖含量呈显著正相关。【结论】LbaSWEET9和LbaSWEET29基因是果糖积累的关键基因。 展开更多
关键词 枸杞 SWEET基因家族 进化分析 表达分析 可溶性糖含量
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基于心功能及IGFBP7、sST2、CGRP、ET分析沙库巴曲缬沙坦在治疗冠心病合并慢性心力衰竭中的应用效果 被引量:2
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作者 张娟 李宁 张文超 《分子诊断与治疗杂志》 2024年第3期472-475,480,共5页
目的 分析冠心病(CHD)合并慢性心力衰竭(CHF)患者应用沙库巴曲缬沙坦治疗的效果。方法 选择2020年1月至2023年1月邯郸市第四医院收治的86例CHD合并CHF患者,以随机数字表法将其分为对照组和试验组各43例。两组CHD治疗均应用硝酸酯类、他... 目的 分析冠心病(CHD)合并慢性心力衰竭(CHF)患者应用沙库巴曲缬沙坦治疗的效果。方法 选择2020年1月至2023年1月邯郸市第四医院收治的86例CHD合并CHF患者,以随机数字表法将其分为对照组和试验组各43例。两组CHD治疗均应用硝酸酯类、他汀类及抗血小板药物,对照组CHF治疗应用坎地沙坦酯片、醛固酮受体拮抗剂及β受体阻滞剂,试验组治疗则将对照组中的坎地沙坦酯片替换为沙库巴曲缬沙坦钠片。比较两组疗效、不良反应、心功能指标[左室短轴缩短率(LVFS)、左室射血分数(LVEF)、6min步行距离(6 MWD)]、心室重构指标[Ⅲ型胶原前肽(PⅢP)、层粘蛋白(LN)、基质金属蛋白酶-9(MMP-9)]、心肌损伤和血管内皮功能相关指标[胰岛素样生长因子结合蛋白7(IGFBP7)、可溶性生长刺激表达基因2(sST2)、降钙素基因相关肽(CGRP)、内皮素(ET)]。结果与对照组比,试验组治疗3个月后的总有效率更高,差异有统计学意义(P<0.05)。两组治疗3个月后的LVFS、LVEF、6 MWD、IGFBP7、CGRP与治疗前比升高,且试验组与对照组比更高,差异有统计学意义(P<0.05);PⅢP、LN、MMP-9、sST2、ET降低,试验组与对照组比更低,差异有统计学意义(P<0.05)。两组不良反应总发生率对比差异无统计学意义(P>0.05)。结论 沙库巴曲缬沙坦可有效调节CHD合并CHF患者IGFBP7、sST2、CGRP、ET,改善血管内皮功能、心肌损伤、心室重构及心功能,进而可提高疗效,且具有良好的安全性。 展开更多
关键词 沙库巴曲缬沙坦 可溶性生长刺激表达基因2 降钙素基因相关肽 内皮素 胰岛素样生长因子结合蛋白7
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丹红注射液联合肝素治疗脓毒症并发急性肾损伤的效果
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作者 李爱林 袁鼎山 +1 位作者 包玉华 蒋海燕 《西北药学杂志》 2024年第1期111-115,共5页
目的探讨丹红注射液联合肝素治疗脓毒症并发急性肾损伤的临床疗效及对血清高迁移率族蛋白B1(high mobility group box 1,HMGB1)和可溶性髓样细胞触发受体-1(soluble triggering receptor expressed on myeloid cells-1,sTREM-1)水平的... 目的探讨丹红注射液联合肝素治疗脓毒症并发急性肾损伤的临床疗效及对血清高迁移率族蛋白B1(high mobility group box 1,HMGB1)和可溶性髓样细胞触发受体-1(soluble triggering receptor expressed on myeloid cells-1,sTREM-1)水平的影响。方法选取收治的80例脓毒症并发急性肾损伤患者作为研究对象,用随机数字表法分为2组,每组40例,2组均予以常规治疗,对照组加用低分子肝素,观察组加用低分子肝素和丹红注射液。对比2组的治疗效果,记录2组治疗前后的血清HMGB1、sTREM-1、肾功能指标及凝血功能指标等的变化。结果与治疗前比较,2组治疗后的各项生命指标、炎症指标、凝血功能指标、肾功能指标、HMGB1及sTREM-1水平均得到明显改善(P<0.05)。与对照组比较,观察组治疗后的体温、心率及急性生理学及慢性健康状况评分系统Ⅱ(acute physiology and chronic health evaluationⅡ,APACHEⅡ)评分均明显更低,血清白细胞介素-6(interleutin-6,IL-6)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、C反应蛋白(C-reactive protein,CRP)、降钙素原(procall⁃citonin,PCT)、血肌酐(screatinine,Scr)、胱抑素C(cystatin C,CysC)、尿素氮(blood urea nitrogen,BUN)、纤维蛋白原(fibrinogen,FIB)及D-二聚体(D-dimer,D-D)的水平均更低,机械通气时间及ICU住院时间明显更短,凝血酶原时间(prothrombin time,PT)明显更长(P<0.05)。2组治疗后的存活率比较差异无统计学意义(P>0.05)。结论丹红注射液联合肝素治疗能够通过抑制sTREM-1、HMGB1的表达,减轻炎症反应,改善凝血功能,增大肾灌注,减轻肾组织损伤,从而治疗脓毒症并发急性肾损伤。 展开更多
关键词 丹红注射液 急性肾损伤 肝素 脓毒症 可溶性髓样细胞触发受体-1
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