A Novel Signal Peptide Derived From Bacillus Licheniformis Α-Amylase Efficiently Targets Recombinant Human Activin A To the Periplasm of Escherichia Coli

Human activin a is a member of the transforming growth factor-β superfamily consists of two similar beta subunits. activin a is expressed by different cells and displays numerous biological activities such as control of neuronal cell proliferation and differentiation, promotion of neuronal survival in the body. therefore, recombinant production of activin a is beneficial because it can be used to treat many neurodegenerative diseases such as alzheimer's and parkinson diseases. in this study e. coli as a cheap and fast-growing host was selected to produce recombinant human activin a. as cytoplasmic expression of human activin a with complex structure and disulfide bonds produces inclusion bodies, so periplasmic expression of it can be beneficial. therefore, we used modified iranian b. licheniformis α-amylase signal peptide as a new signal peptide in order to translocate the recombinant activin a through the inner membrane. in this study human pro-activin a cdna and signal sequence were cloned in pet21b vector and resulting vector transformed into the two strains of e. coli bl21. sds-page and western blot techniques were used to confirm recombinant activin a expression. finally, our results indicated that the signal peptide used in this study was effective for secretion of activin a into the periplasmic space of e. coli