In silico design and evaluation of signal peptide for secretory expression of interferon a۲b in E. coli

Backgrounds: Interferons are a group of signaling glycoproteins that belong to a large group ofcytokines and are a group of proteins that are released from virus-infected host cells. Most of therecombinant proteins are produced in E. coli; it has many advantages in the production ofheterologous recombinant proteins. The inability of proteins to fold rapidly to form naturalstructures turns them into insoluble substances called inclusion bodies or inactive proteins. Oneapproach to solve this problem is to transfer heterologous proteins to the periplasmic space ofbacterial hosts using a suitable signal peptide at the N-terminal end of the protein. Expression inthe periplasmic space creates an excellent space for proper bonding and twisting. Proteinimpurities and protease activity in the periplasm are less than in the cytoplasm. This study isbased on structural understanding and finding the appropriate signal peptide for the secretoryexpression of interferon a۲b in E. coli.Materials and Methods: For this purpose, the amino acid sequence of ۶۱ signal peptides wasobtained using bioinformatics software and then their physicochemical properties andintracellular location were predicted by in silico methods and inappropriate signal peptides wereremoved. The selected signal peptides for the high levels of secretory expression in the E. colihost were compared and measured.Results: Based on the analysis and research, most of the signal peptides associated withinterferon a۲b are in the space around the periplasm. Interferon a۲b was insoluble in fusion withmost signal peptides.Conclusion: Base on results, sfm C, flgL, ompC are signal peptides showed the highest scoreand found as most suitable signal peptides for periplasmic expression of IFN-a۲b.

کلیدواژه ها:

Interferon a۲b ، Signal peptide ، Secretory production ، E. coli ، in silico