Enhancement of recombinant protein expression in Escherichia coli through fusion with short disordered peptides

The prokaryotic expression system has been employed extensively for the production of recombinant proteins. Nevertheless, some proteins are particularly challenging to express at the large-scale production level. One strategy for enhancing the expression of target proteins in host cells is the use of fusion tags. The two short-disordered peptides (LEA II and LEA K) were derived from the group 3 late embryogenesis abundant protein (G3LEA) of Polypedilum vanderplanki, comprising 13 amino acid residues. The objective of this study was to investigate the potential of LEA II and LEA K (LEA-tags) as a means of increasing protein expression at low temperatures, with a particular focus on proteins that are challenging to express. To validate the efficacy of LEA tags as an expression enhancer for improving protein production, green fluorescent protein (GFP), lipase (lip) derived from Bacillus licheniformis, and silicatein-α (sil) derived from Suberites domuncula were employed as model proteins to assess the extent of their enhanced expression following fusion with LEA tags. LEA II improved the expression of lip and sil by 18- and 21-fold, respectively; LEA K improved it by 11- and 18-fold, respectively. Notably, LEA II increased the soluble expression of lipase and silicatein. The protein yield increased without impairing protein function. Using LEA tags represents a promising approach for enhancing the production of challenging proteins in Escherichia coli.