Expression, Purification and Characterization of Amantadine Receptor in Escherichia coli

2012 ◽  
Vol 161 ◽  
pp. 88-93 ◽  
Author(s):  
Hai Xin Sun ◽  
Li Min Cao ◽  
Hong Lin ◽  
Fang Lv

In order to obtain large quantities of broadly selective receptor as one diagnose agent to detect amantadine residue, the M2 protein gene with a His-tag was ligated into pET11a and transferred into E. coli BL21 (DE3) cell. The recombinant E. coli was cultured in liquid LB culture. SDS-PAGE result showed the recombinant M2 protein (rM2) was expressed as insoluble inclusion bodies with about 18KDa in molecular size. rM2 protein was further recognized by Western blot and purified by Ni Sepharose 6 Fast Flow and then refolded. The equilibrium dialysis result showed the rM2 protein had the binding constant of 1.1×105, and stoichiometry of 4.2. The above result showed the rM2 has the potential as biological diagnose agent to the detection of amantadine residue.

2004 ◽  
Vol 36 (2) ◽  
pp. 118-122 ◽  
Author(s):  
Xiao-Xia Xia ◽  
Ya-Ling Shen ◽  
Dong-Zhi Wei

Abstract As a potential anti-tumor protein, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has drawn considerable attention. This report presented the purification and characterization of soluble TRAIL, expressed as inclusion bodies in E. coli. sTRAIL inclusion bodies were solubilized and refolded at a high concentration up to 0.9 g/L by a simple dilution method. Refolded protein was purified to electrophoretic homogeneity by a single-step immobilized metal affinity chromatography. The purified sTRAIL had a strong cytotoxic activity against human pancreatic tumor cell line 1990, with ED50 about 1.5 mg/L. Circular dichroism and fluorescence spectrum analysis showed that the refolded sTRAIL had a structure similar to that of native protein with β-sheet secondary structure. This efficient procedure of sTRAIL renaturation may be useful for the mass production of this therapeutically important protein.


2019 ◽  
Vol 8 (1) ◽  
pp. 8-17
Author(s):  
Pavan Kumar Vadla ◽  
Murali Tummuru ◽  
Dinesh Kumar

Streptokinase is a extracellular enzyme which is extracted from strains of beta Hemolytic streptococcus. The enzyme is a non-protease plasminogen activator that activates plasminogen to plasmin and degrades fibrin clot through its specific lysine binding site which is used in thrombolytic therapy. Purification of streptokinase produced from S.equisimilis in E.coli with N-terminal methionine was carried out in 3 Chromatography purification steps, 1) CM-Sepharose-FF at pH 4.2 followed by concentration and dialysis over night with Tris-HCl pH 8.0. Partially purified dialyzed enzyme sample was loaded on to 2) DEAE-Sepharose-FF column. The Purified fractions of DEAE column were pooled and applied on to Sephadex G-100 column. Enzyme purity was confirmed by SDS-PAGE and RP-HPLC.Its biological activity is determined by specific streptokinase assay and characterised the enzyme by Peptide mapping, MALDI-TOF, Isoelectric-focusing and RP-HPLC. The isoelectric point (pI) of streptokinase is around 4.98.The results of characterization shows that it contains two forms (Isomers) of streptokinase expressed in E. coli which was analyzed by RP-HPLC and chromogenic assay. The variation is formed by isomer-1 in which 85% of Streptokinase expressed without methionine (85000IU/mg) and Isomer-2 in which 15% of streptokinase expressed with methionine (nil activity) in E. coli. This phenomenon shows that the presence and absence of methionine in isomers of streptokinase varying the catalytic activity of the enzyme.


2000 ◽  
Vol 347 (2) ◽  
pp. 383-388 ◽  
Author(s):  
Sanya J. SANDERSON ◽  
Kevin G. J. POLLOCK ◽  
James D. HILLEY ◽  
Morten MELDAL ◽  
Phaedria ST HILAIRE ◽  
...  

A major cysteine proteinase (CPB) of Leishmania mexicana, that is predominantly expressed in the form of the parasite that causes disease in mammals, has been overexpressed in Escherichia coli and purified from inclusion bodies to apparent homogeneity. The CPB enzyme, CPB2.8, was expressed as an inactive pro-form lacking the characteristic C-terminal extension (CPB2.8∆CTE). Pro-region processing was initiated during protein refolding and proceeded through several intermediate stages. Maximum enzyme activity accompanied removal of the entire pro-region. This was facilitated by acidification. Purified mature enzyme gave a single band on SDS/PAGE and gelatin SDS/PAGE gels, co-migrated with native enzyme in L. mexicana lysates, and had the same N-terminal sequence as the native enzyme. The procedure yielded > 3.5 mg of active enzyme per litre of E. coli culture.


2021 ◽  
Vol 184 ◽  
pp. 105878
Author(s):  
Carla Lizbeth Segovia-Trinidad ◽  
Bastian Quaas ◽  
Zhaopeng Li ◽  
Antonina Lavrentieva ◽  
Yvonne Roger ◽  
...  

2006 ◽  
Vol 52 (7) ◽  
pp. 651-657 ◽  
Author(s):  
Luis Morales de la Vega ◽  
J Eleazar Barboza-Corona ◽  
Maria G Aguilar-Uscanga ◽  
Mario Ramírez-Lepe

A chitinolytic enzyme from Bacillus thuringiensis subsp. aizawai has been purified and its molecular mass was estimated ca. 66 kDa by sodium dodecyl sulfate – polyacryamide gel electrophoresis (SDS–PAGE). The enzyme was able to hydrolyze chitin to chitobiosides but not carboxymethylcellulose, cellulose, pullulan, and laminarin. Optimal pH and temperature were detected at 6 and 50 °C, respectively. Stability, in the absence of substrate, was observed at temperatures less than 60 °C and pH between 5 and 8. Enzyme activity was significantly inhibited by K+ and EDTA and completely inhibited by Hg2+. Purified chitinase showed lytic activity against cell walls from six phytopathogenic fungi and inhibited the mycelial growth of both Fusarium sp. and Sclerotium rolfsii. The biocontrol efficacy of the enzyme was tested in the protection of bean seeds infested with six phytopathogenic fungi.Key words: chitinase, Bacillus thuringiensis, purification, phytopathogenic fungi.


2017 ◽  
Vol 18 (2) ◽  
pp. 1-10 ◽  
Author(s):  
Dzun Noraini Jimat ◽  
Intan Baizura Firda Mohamed ◽  
Azlin Suhaida Azmi ◽  
Parveen Jamal

A newly bacterial producing L-asparaginase was successful isolated from Sungai Klah Hot Spring, Perak, Malaysia and identified as Bacillus sp. It was the best L-asparaginase producer as compared to other isolates. Production of L-asparaginase from the microbial strain was carried out under liquid fermentation. The crude enzyme was then centrifuged and precipitated with ammonium sulfate before further purified with chromatographic method. The ion exchange chromatography HiTrap DEAE-Sepharose Fast Flow column followed by separation on Superose 12 gel filtration were used to obtain pure enzyme. The purified enzyme showed 10.11 U/mg of specific activity, 50.07% yield with 2.21 fold purification. The purified enzyme was found to be dimer in form, with a molecular weight of 65 kDa as estimated by SDS-PAGE. The maximum activity of the purified L-asparaginase was observed at pH 9 and temperature of 60°C.


Author(s):  
Nguyen Thi My Trinh ◽  
Tran Linh Thuoc ◽  
Dang Thi Phuong Thao

Background: The recombinant human granulocyte colony stimulating factor con-jugated with polyethylene glycol (PEGylated GCSF) has currently been used as an efficient drug for the treatment of neutropenia caused by chemotherapy due to its long circulating half-life. Previous studies showed that Granulocyte Colony Stimula-ting Factor (GCSF) could be expressed as non-classical Inclusion Bodies (ncIBs), which contained likely correctly folded GCSF inside at low temperature. Therefore, in this study, a simple process was developed to produce PEGylated GCSF from ncIBs. Methods: BL21 (DE3)/pET-GCSF cells were cultured in the LiFlus GX 1.5 L bioreactor and the expression of GCSF was induced by adding 0.5 mM IPTG. After 24 hr of fermentation, cells were collected, resuspended, and disrupted. The insoluble fraction was obtained from cell lysates and dissolved in 0.1% N-lauroylsarcosine solution. The presence and structure of dissolved GCSF were verified using SDS-PAGE, Native-PAGE, and RP-HPLC analyses. The dissolved GCSF was directly used for the con-jugation with 5 kDa PEG. The PEGylated GCSF was purified using two purification steps, including anion exchange chromatography and gel filtration chromatography. Results: PEGylated GCSF was obtained with high purity (~97%) and was finally demonstrated as a form containing one GCSF molecule and one 5 kDa PEG molecule (monoPEG-GCSF). Conclusion: These results clearly indicate that the process developed in this study might be a potential and practical approach to produce PEGylated GCSF from ncIBs expressed in Escherichia coli (E. coli).


2007 ◽  
Vol 55 (2) ◽  
pp. 312-318 ◽  
Author(s):  
Ziyong Sun ◽  
Wei Lu ◽  
Yanchun Tang ◽  
Jing Zhang ◽  
Junyong Chen ◽  
...  

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