scholarly journals Expression and Hydroxylamine Cleavage of Thymosin Alpha 1 Concatemer

2008 ◽  
Vol 2008 ◽  
pp. 1-8 ◽  
Author(s):  
Liang Zhou ◽  
Zong-Teng Lai ◽  
Min-Kan Lu ◽  
Xing-Guo Gong ◽  
Yi Xie
Keyword(s):  
Mass Spectrometry ◽  
Lymphocyte Proliferation ◽  
Expression Vector ◽  
Mitochondrial Activity ◽  
Tumor Cell Lines ◽  
E Coli ◽  
Sds Page ◽  
Thymosin Alpha 1 ◽  
Codon Usage Preference ◽  
Usage Preference

Human thymosin alpha 1 (Tα1) is an important peptide in the development and senescence of immunological competence in human, and many studies have reported the expression of this peptide. In this study, we designed and synthesized theTα1gene according to theE. colicodon usage preference and constructed a 6×Tα1 concatemer. The latter was inserted into anE. coliexpression vector pET-22b (+), and transformed intoE. coliBL21 (DE3). After induction with IPTG, the concatemer protein was successfully expressed inE. colithen cleaved by hydroxylamine to release the Tα1 monomer. Gly-SDS-PAGE and mass spectrometry confirmed that the recombinant protein was cleaved as intended. The bioactivity of the Tα1 monomer was analyzed by lymphocyte proliferation and by mitochondrial activity in two different tumor cell lines. This study provides a description of the preparation of a bioactive Tα1, which may prove useful in future biomedical research.

Construction of Prokaryotic Expression Vector Containing Flocculation Gene FLO5 and Expression of FLO5 in E. coli

2013 ◽  
Vol 310 ◽  
pp. 157-161 ◽  
Author(s):  
Jie Xue ◽  
Wen Qiang Wei ◽  
Dong Yan Zhang ◽  
Yong Li Li ◽  
Xin Zhang ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Prokaryotic Expression ◽  
Genomic Dna ◽  
Expression Vector ◽  
Gene Fragment ◽  
Form Expression ◽  
Protein Fragments ◽  
E Coli ◽  
Sds Page ◽  
Prokaryotic Expression Vector

FLO5 has been identified as a dominant flocculation gene. The goal of this study is to clone the FLO5 gene from Saccharomyces cerevisiae and express it in E. coli. In this study, the FLO5 gene amplified by PCR from S. cerevisiae was cloned into prokaryotic expression vector pET-28a to form expression vector pET28a-FLO5, finally, transferred into E.coli BL21. Methods: FLO5 gene was amplified by PCR from genomic DNA extracted from Saccharomyces cerevisiae. The amplified FLO5 gene fragment was then recombined with clone vector pMD18-T to form clone vector pMD18-T-FLO5 amplified in E.coli JM109. After confirmed with sequencing, FLO5 fragment cut out from pMD18-T-FLO5 by enzyme EcoRI and NotI was recombined into expression vector pET-28a to form vector pET28a-FLO5. Vector pET28a-FLO5 was then transferred into E. coli BL21 and protein FLO5 was expressed in E. coli BL21 by the induction with IPTG. Expressed protein fragments separated by SDS-PAGE showed a band with the size of protein FLO5 suggesting the expression of gene FLO5. with the expected This study will lay the foundation for further research in studying flocculating effect of exogenous protein expressed by genetic engineering and making new flocculating agent through recombinant engineering.

Expression of a Modified Cry1Ie Gene in E. coli and in Transgenic Tobacco Confers Resistance to Corn Borer

2004 ◽  
Vol 36 (4) ◽  
pp. 309-313 ◽  
Author(s):  
Yun-Jun Liu ◽  
Fu-Ping Song ◽  
Kang-Lai He ◽  
Yuan Yuan ◽  
Xiao-Xia Zhang ◽  
...  
Keyword(s):  
Transgenic Tobacco ◽  
Prokaryotic Expression ◽  
Expression Vector ◽  
Wild Type ◽  
Corn Borer ◽  
E Coli ◽  
Plant Expression Vector ◽  
Sds Page ◽  
Prokaryotic Expression Vector ◽  
Efficient Expression

Abstract The wild-type Cry1Ie gene from Bacillus thuringiensis was modified for its efficient expression in transgenic plants. Modified Cry1Ie gene (designated as Cry1Iem) was cloned into prokaryotic expression vector pET28b and its expression in E. coli was confirmed by SDS-PAGE analysis. Bioassays using crude expression products in E. coli revealed that Cry1Iem protein had a similar toxicity to corn borer as wild-type Cry1Ie. Cry1Iem gene was then inserted downstream of the maize ubiquitin-1 promoter in plant expression vector p3301. Transgenic tobacco plants carrying Cry1Iem showed insecticidal activity against corn borer.

Expression and Purification of His-chIFN-α and its Antiviral Activity Assay

2013 ◽  
Vol 750-752 ◽  
pp. 1515-1519
Author(s):  
Yue Ma ◽  
Min Hui Long ◽  
Ai Po Diao
Keyword(s):  
Antiviral Activity ◽  
Expression Vector ◽  
Recombinant Expression ◽  
Metal Chelate ◽  
Activity Assay ◽  
Expression And Purification ◽  
E Coli ◽  
Sds Page ◽  
Recombinant Expression Vector ◽  
Metal Chelate Affinity Chromatography

In this paper, Chicken alpha interferon (IFN-α) gene was cloned into pUC19-His expression vector, then the recombinant expression vector was transformed into host bacteria E. coli BL21. The recombinant chicken IFN-α was induced to express by IPTG, then the protein expression was analyzed with SDS-PAGE. Under the condition that the recombinant protein was induced to express with 1 mM IPTG at 37 °C, the expressed protein was inclusion body. His-chIFN-α was purified by Ni-metal chelate affinity chromatography. His-chIFN-α was shown to inhibit the replication of Newcastle disease virus in CEF cells.

Optics-Free Visualization of Proteins in Single Cells by Time of Flight-Secondary Ion Mass Spectrometry Coupled with Genetically Encoded Chemical Tags

2020 ◽  
Author(s):  
Feifei Jia ◽  
Jie Wang ◽  
Yanyan Zhang ◽  
Qun Luo ◽  
Luyu Qi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Single Cells ◽  
Time Of Flight ◽  
E Coli ◽  
Tof Sims ◽  
Ion Mass Spectrometry ◽  
Chemical Tags ◽  
Secondary Ion

<p></p><p><i>In situ</i> visualization of proteins of interest at single cell level is attractive in cell biology, molecular biology and biomedicine, which usually involves photon, electron or X-ray based imaging methods. Herein, we report an optics-free strategy that images a specific protein in single cells by time of flight-secondary ion mass spectrometry (ToF-SIMS) following genetic incorporation of fluorine-containing unnatural amino acids as a chemical tag into the protein via genetic code expansion technique. The method was developed and validated by imaging GFP in E. coli and human HeLa cancer cells, and then utilized to visualize the distribution of chemotaxis protein CheA in E. coli cells and the interaction between high mobility group box 1 protein and cisplatin damaged DNA in HeLa cells. The present work highlights the power of ToF-SIMS imaging combined with genetically encoded chemical tags for <i>in situ </i>visualization of proteins of interest as well as the interactions between proteins and drugs or drug damaged DNA in single cells.</p><p></p>

Enhanced Biocatalytic Activity of Recombinant Lipase Immobilized on Gold Nanoparticles

2019 ◽  
Vol 20 (6) ◽  
pp. 497-505 ◽  
Author(s):  
Abeer M. Abd El-Aziz ◽  
Mohamed A. Shaker ◽  
Mona I. Shaaban
Keyword(s):  
Gold Nanoparticles ◽  
Lipolytic Activity ◽  
Market Demand ◽  
Biotechnological Applications ◽  
Lipase Gene ◽  
Expression Plasmid ◽  
E Coli ◽  
Nickel Affinity Chromatography ◽  
Recombinant Production ◽  
Sds Page

Background: Bacterial lipases especially Pseudomonas lipases are extensively used for different biotechnological applications. Objectives: With the better understanding and progressive needs for improving its activity in accordance with the growing market demand, we aimed in this study to improve the recombinant production and biocatalytic activity of lipases via surface conjugation on gold nanoparticles. Methods: The full length coding sequences of lipase gene (lipA), lipase specific foldase gene (lipf) and dual cassette (lipAf) gene were amplified from the genomic DNA of Pseudomonas aeruginosa PA14 and cloned into the bacterial expression vector pRSET-B. Recombinant lipases were expressed in E. coli BL-21 (DE3) pLysS then purified using nickel affinity chromatography and the protein identity was confirmed using SDS-PAGE and Western blot analysis. The purified recombinant lipases were immobilized through surface conjugation with gold nanoparticles and enzymatic activity was colorimetrically quantified. Results: Here, two single expression plasmid systems pRSET-B-lipA and pRSET-B-lipf and one dual cassette expression plasmid system pRSET-B-lipAf were successfully constructed. The lipolytic activities of recombinant lipases LipA, Lipf and LipAf were 4870, 426 and 6740 IUmg-1, respectively. However, upon immobilization of these recombinant lipases on prepared gold nanoparticles (GNPs), the activities were 7417, 822 and 13035 IUmg-1, for LipA-GNPs, Lipf-GNPs and LipAf-GNPs, respectively. The activities after immobilization have been increased 1.52 and 1.93 -fold for LipA and LipAf, respectively. Conclusion: The lipolytic activity of recombinant lipases in the bioconjugate was significantly increased relative to the free recombinant enzyme where immobilization had made the enzyme attain its optimum performance.

scholarly journals Effect of Ocular Hypertension on D-β-Aspartic Acid-Containing Proteins in the Retinas of Rats

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Takashi Kanamoto ◽  
Takashi Tachibana ◽  
Yasushi Kitaoka ◽  
Toshio Hisatomi ◽  
Yasuhiro Ikeda ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Ocular Hypertension ◽  
Aspartic Acid ◽  
Atp Synthase ◽  
Wistar Rats ◽  
Protein Band ◽  
Mass Spectrometry Analysis ◽  
Liquid Chromatography Mass Spectrometry ◽  
Spectrometry Analysis ◽  
Sds Page

Purpose. To investigate the effect of ocular hypertension-induced isomerization of aspartic acid in retinal proteins. Methods. Adult Wistar rats with ocular hypertension were used as an experimental model. D-β-aspartic acid-containing proteins were isolated by SDS-PAGE and western blot with an anti-D-β-aspartic acid antibody and identified by liquid chromatography-mass spectrometry analysis. The concentration of ATP was measured by ELISA. Results. D-β-aspartic acid was expressed in a protein band at around 44.5 kDa at much higher quantities in the retinas of rats with ocular hypertension than in those of normotensive rats. The 44.5 kDa protein band was mainly composed of α-enolase, S-arrestin, and ATP synthase subunits α and β, in both the ocular hypertensive and normotensive retinas. Moreover, increasing intraocular pressure was correlated with increasing ATP concentrations in the retinas of rats. Conclusion. Ocular hypertension affected the expression of proteins containing D-β-aspartic acid, including ATP synthase subunits, and up-regulation of ATP in the retinas of rats.

scholarly journals Characterization of a novel + 70 Da modification in rhGM-CSF expressed in E. coli using chemical assays in combination with mass spectrometry

Amino Acids ◽  
2021 ◽  
Author(s):  
Magdalena Widgren Sandberg ◽  
Jakob Bunkenborg ◽  
Stine Thyssen ◽  
Martin Villadsen ◽  
Thomas Kofoed
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Peptide Mapping ◽  
Covalent Modification ◽  
Peptide Fragmentation ◽  
Tandem Mass ◽  
E Coli ◽  
Gm Csf ◽  
Fragmentation Behavior ◽  
Macrophage Colony

AbstractGranulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine and a white blood cell growth factor that has found usage as a therapeutic protein. During analysis of different fermentation batches of GM-CSF recombinantly expressed in E. coli, a covalent modification was identified on the protein by intact mass spectrometry. The modification gave a mass shift of + 70 Da and peptide mapping analysis demonstrated that it located to the protein N-terminus and lysine side chains. The chemical composition of C4H6O was found to be the best candidate by peptide fragmentation using tandem mass spectrometry. The modification likely contains a carbonyl group, since the mass of the modification increased by 2 Da by reduction with borane pyridine complex and it reacted with 2,4-dinitrophenylhydrazine. On the basis of chemical and tandem mass spectrometry fragmentation behavior, the modification could be attributed to crotonaldehyde, a reactive compound formed during lipid peroxidation. A low recorded oxygen pressure in the reactor during protein expression could be linked to the formation of this compound. This study shows the importance of maintaining full control over all reaction parameters during recombinant protein production.

Application of 2D BN/SDS-PAGE coupled with mass spectrometry for identification of VDAC-associated protein complexes related to mitochondrial binding sites for type I brain hexokinase

Mitochondrion ◽  
2013 ◽  
Vol 13 (6) ◽  
pp. 823-830 ◽  
Author(s):  
Carla Rossini Crepaldi ◽  
Phelipe Augusto Mariano Vitale ◽  
Andrea Cristina Tesch ◽  
Hélen Julie Laure ◽  
José César Rosa ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Binding Sites ◽  
Protein Complexes ◽  
Type I ◽  
Sds Page

scholarly journals Cloning of Salmonella enterica Serovar Enteritidis Fimbrial Protein SefA as a Surface Protein in Escherichia coli Confers the Ability To Attach to Eukaryotic Cell Lines

2009 ◽  
Vol 75 (20) ◽  
pp. 6622-6625 ◽  
Author(s):  
Douglas L. Rank ◽  
Mahdi A. Saeed ◽  
Peter M. Muriana
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Expression Vector ◽  
Surface Protein ◽  
Surface Expression ◽  
Eukaryotic Cell ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Western Blot Assay ◽  
E Coli ◽  
Fimbrial Protein

ABSTRACT The gene for the Salmonella enterica serovar Enteritidis fimbrial protein SefA was cloned into an Escherichia coli surface expression vector and confirmed by Western blot assay. E. coli clones expressing SefA attached to avian ovary granulosa cells and HEp-2 cells, providing evidence for the involvement of SefA in the ability of Salmonella to attach to eukaryotic cells.

HPLC and 252Cf Plasma Desorption-Mass Spectrometry of Muropeptides Isolated from E. Coli

1993 ◽  
pp. 31-38 ◽  
Author(s):  
Ernst Pittenauer ◽  
Marta Caparros Rodriguez ◽  
Miguel A. dePedro ◽  
Günter Allmaier ◽  
Erich R. Schmid
Keyword(s):  
Mass Spectrometry ◽  
Desorption Mass Spectrometry ◽  
Plasma Desorption Mass Spectrometry ◽  
E Coli ◽  
Plasma Desorption
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