Development of novel surface display platforms for anchoring heterologous proteins in Saccharomyces cerevisiae

Xiaoyu Yang,Hongting Tang,Yu Shen,Jin Hou,Meihui Song,Xiaoming Bao

doi:10.1186/s12934-019-1133-x

Abstract

BackgroundCell surface display of recombinant proteins has become a powerful tool for biotechnology and biomedical applications. As a model eukaryotic microorganism, Saccharomyces cerevisiae is an ideal candidate for surface display of heterologous proteins. However, the frequently used commercial yeast surface display system, the a-agglutinin anchor system, often results in low display efficiency.ResultsWe initially reconstructed the a-agglutinin system by replacing two anchor proteins with one anchor protein. By directly fusing the target protein to the N-terminus of Aga1p and inserting a flexible linker, the display efficiency almost doubled, and the activity of reporter protein α-galactosidase increased by 39%. We also developed new surface display systems. Six glycosylphosphatidylinositol (GPI) anchored cell wall proteins were selected to construct the display systems. Among them, Dan4p and Sed1p showed higher display efficiency than the a-agglutinin anchor system. Linkers were also inserted to eliminate the effects of GPI fusion on the activity of the target protein. We further used the newly developed Aga1p, Dan4p systems and Sed1p system to display exoglucanase and a relatively large protein β-glucosidase, and found that Aga1p and Dan4p were more suitable for immobilizing large proteins.ConclusionOur study developed novel efficient yeast surface display systems, that will be attractive tools for biotechnological and biomedical applications

Highlights

Cell surface display of recombinant proteins has become a powerful tool for biotechnology and biomedical applications
Optimization of a‐agglutinin anchor system to improve surface display efficiency a-Agglutinin is a cell wall protein consisting of Aga1p and Aga2p
The display of a heterologous protein depends on the formation of two disulfide bonds between Aga1p and Aga2p, which may result in low display efficiency

Summary

Introduction

Cell surface display of recombinant proteins has become a powerful tool for biotechnology and biomedical applications. As a model eukaryotic microorganism, Saccharomyces cerevisiae is an ideal candidate for surface display of heterologous proteins. As a eukaryotic model microorganism, Saccharomyces cerevisiae (S. cerevisiae) is ideal for cell surface display because: (i) it is a “generally regarded as safe” microorganism; (ii) it is suitable for expressing eukaryotic proteins because post-translational modifications are conserved in eukaryotic organisms; (iii) its clear genetic background facilitates diverse genetic engineering; and (iv) its rapid growth is time-saving [1]. In S. cerevisiae, the cell wall proteins are composed of two major classes—: (i) glycosylphosphatidylinositol (GPI) proteins, and (ii) the family of proteins with internal repeats (PIR) [8]. GPI proteins contain a GPI anchor which is synthesized in the endoplasmic reticulum and transferred to the carboxyl terminus of the protein. These proteins are transported to the cell wall through the

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Conclusion