TAILIEUCHUNG - Báo cáo Y học: Extra terminal residues have a profound effect on the folding and solubility of a Plasmodium falciparum sexual stage-specific protein over-expressed in Escherichia coli

The presence of extraN- andC- terminal residues can play a major role in the stability, solubility and yield of recombi-nant proteins. Pfg27 is a 27Ksoluble protein that is essential for sexual development in Plasmodium was over-expressed using the pMAL-p2 vector as a fusion pro-teinwith themaltosebindingprotein. Sixdifferent constructs were made and each of the fusion proteins were expressed and purified. | Eur. J. Biochem. 269 5259-5263 2002 FEBS 2002 doi Extra terminal residues have a profound effect on the folding and solubility of a Plasmodium falciparum sexual stage-specific protein over-expressed in Escherichia coli Sushil Prasad Sati1 Saurabh Kumar Singh1 Nirbhay Kumar2 and Amit Sharma1 1Malaria Group International Centre for Genetic Engineering and Biotechnology Aruna Asaf AH Marg New Delhi India department of Molecular Microbiology and Immunology Hopkins Malaria Research Institute The Johns Hopkins University Bloomberg School of Public Health Baltimore Maryland USA The presence of extra N- and C- terminal residues can play a major role in the stability solubility and yield of recombinant proteins. Pfg27 is a 27K soluble protein that is essenial 1 for sexual development in Plasmodium falciparum. It was over-expressed using the pMAL-p2 vector as a fusion protein with the maltose binding protein. Six different constructs were made and each of the fusion proteins were expressed and purified. Our results show that the fusion proteins were labile and only partially soluble in five of the constructs resulting in very poor yields. Intriguingly in the sixth construct the yield of soluble fusion protein with an extended carboxyl terminus of 17 residues was several fold higher. Various constructs with either N-terminal or smaller C-ter-minal extensions failed to produce any soluble fusion protein. Furthermore all five constructs produced Pfg27 that precipitated after protease cleavage from its fusion partner. The sixth construct which produced soluble protein in high yields also gave highly stable and soluble Pfg27 after cleavage of the fusion. These results indicate that extra amino acid residues at the termini of over-expressed proteins can have a significant effect on the folding of proteins expressed in E. coli. Our data suggest the potential for development of a novel methodology which will entail construction of fusion proteins .

• Báo cáo khoa học
• Report medicine
• traditional medicine
• scientific reports
• medical research
• hemoglobin
• medical knowledge
• analysis of cytoplasmic
• oxidation
• Crystal structure
• bacteria
• medicine
• cell proliferation
• breast cancer
• chemical reaction
• gastric cancer
• hormone medicine
• tumor cells
• biochemical studies
• environmental medicine