Expression of codon-optimized TgMIC16 in three Escherichia coli strains

Abstract

In a previous study, we found that rabbit anti- serum was capable of recognizing truncated microneme protein 16 (TgMIC16), indicating that TgMIC16 is an essential antigenic protein. However, the broad application of this recombinant protein is limited by its low expression level. In this study, we performed codon optimization of by changing the codon-adaptation index from 0.22 to 1.0 without altering the amino acid sequence and expressed the optimized gene in three different strains, followed by comparison of soluble recombinant-protein expression and yield. Our results showed that the recombinant protein rTgMIC16 was expressed as inclusion bodies in all three strains following optimization of induction parameters, and western blot analysis revealed the presence of a ~72-kD recombinant protein as a specific band following purification. A shuffle-expression strain was selected to amplify incubation products and induce expression, resulting in an overall rTgMIC16 yield of ~20 mg/L. These findings provide a basis for further investigation of TgMIC16 to elucidate its functions and interaction partners.

Codon optimization, expression in Escherichia coli, and immunogenicity analysis of deformed wing virus (DWV) structural protein

“…Comparing the codon usage in E. coli, we found many rare codons in the wild DWV structural protein genes and CAI values of the three target genes were only approximately 0.2; this likely results in lower expression yields-even expression failure-in E. coli. Codon optimization can improve protein production via optimization of translation elongation and previous reports have shown that a codon-optimization strategy can improve the expression level of genes in many species (Chu et al, 2018;Hu et al, 2019;Nieuwkoop, Claassens & Van der Oost, 2019;Sun et al, 2017). In this study, the rare codons of DWV VP1, VP2 and VP3 were replaced with the most highly preferred codons and the GC content was changed to approximately 70%.…”