Abstract
Background: Solubility of recombinant therapeutic enzymes is one of the major purpose their production in bacterial host The factors such as metabolic system, a cellular stress response of the bacterial host and formation of inclusion bodies cause undesirable expression results. One method to overcome this problem is secretion of recombinant protein into the extracellular growth medium by selection of proper signal peptides. Reteplase (Retavase) is a serine protease simulating endogenous tissue plasminogen activator (t-PA), fibrin-specific plasminogen activator, playing role in thrombolysis and fibrinolysis (clot lysis) by converting plasminogen to plasmin.
Objective: The aim of this study was to evaluate several signal peptides in order to selection the proper one which suitable for excretory production of the reteplase.
Method: The presence and cleavage site location in signal peptides was predicted by SignalP 4.1. The prediction of secretory pathway of signal peptides was performed using high accurate database. Several critical features of the signal peptide were evaluated applying various online web-servers such as ProtParam and Solpro with high sensitivity and specificity. Finally, the selected signal peptides were compared and the one which was appropriate candidate for high yields production of secretory reteplase in the E. coli host was defined.
Results: Among total 30 signal peptides, 6 of them, CHIS_BACSU, MPT53_MYCTU, PET_ECOLX, PIC_ECOL6, PIC_ECLOX, TSH_ECOLX were omitted. CPLR_DESHA, AGAR_ALTAT, CDGT_BACS2, PAG_BACAN could be considered as proper candidate for efficient extracellular production of reteplase in E. coli.
Conclusion: Theoretical analysis and evaluation of signal peptides by using computational tools can be acceptably carried out, but these results must be established via practical effort.
Keywords: E. coli host, bioinformatics, secretion, physicochemical properties, solubility, signal peptides.
Graphical Abstract