The Effect of Monomers Number in Peptides on Escherichia Coli Strain Productivity and Inclusion Bodies Quality

This study aimed to determine the optimal cultivation conditions for four E. coli strains producing recombinant glucagon-like peptide-1 (GLP-1) tandems. Validation experiments confirmed that scale-up from shake flasks to a bioreactor is feasible without significant loss of specific productivity. We also demonstrated that the optimal cultivation conditions are identical for all tested strains. However, the number of GLP-1 monomers in the tandem influenced the final yield in both shake flasks and the bioreactor. The quality of the resulting inclusion bodies (IBs) was also evaluated. The IB content per gram of biomass was found to correlate with specific productivity, and IB quality varied among the different tandems. A correlation was identified between the titer of the GLP-1 tandems and the number of monomers. The results indicate that selecting the appropriate number of monomers during strain development can enhance productivity, improve inclusion body quality, and increase the final product titer after downstream processing.