Yeast Surface Display Yields Reusable Cellulase Biocatalysts

Researchers have developed a method for constructing high-efficiency cellulosic biocatalysts using the yeast Pichia pastoris. The study, published in AMB Express, addresses the significant barriers to industrial biomass conversion, specifically the high cost and limited stability of traditional cellulase enzymes. By utilizing yeast surface display technology, the team aimed to create reusable whole-cell catalysts that could overcome these economic and operational challenges. The research focuses on the compatibility between different anchor proteins and specific cellulase components, a factor that has previously remained unclear.

The study utilized Pichia pastoris X33 as the host strain to construct nine distinct recombinant strains. The researchers fused three different anchor proteins, identified as PIR1, SED1, and AGA1, with three key cellulase components: endoglucanase (EG), cellobiohydrolase (CBH), and beta-glucosidase (BGL).

Among the three anchor proteins tested, PIR1 demonstrated markedly higher display efficiency for all three enzymes compared to the alternatives, SED1 and AGA1. This finding highlights the importance of anchor protein selection in the rational design of whole-cell biocatalysts. The specific combination of endoglucanase and the PIR1 anchor, referred to as EG-PIR1, achieved the highest display efficiency among all tested configurations. Flow cytometry quantification revealed that this combination reached a display efficiency of 91.5%, indicating a highly effective surface presentation of the enzyme.

The researchers then proceeded with fermentation optimization. This process resulted in a significant increase in enzyme activity, which surged to 0.594 U/mL. This level of activity represented a 42.2% improvement over the pre-optimization levels.

A critical advantage of the developed biocatalysts is their reusability, which directly addresses the cost barriers associated with traditional enzyme systems. The surface-displayed enzymes retained over 75% of their relative activity after six consecutive cycles of reuse.

The study provides a quantitative elucidation of the adaptation patterns between anchor proteins and cellulase components. By systematically varying the anchor proteins and measuring the resulting display efficiencies, the researchers established a theoretical foundation for the rational design of highly efficient whole-cell biocatalysts.

Subject of Research: Construction of reusable whole-cell cellulase biocatalysts via Pichia pastoris surface display

Article Title: High-efficiency cellulosic biocatalysts constructed via Pichia pastoris surface display

Article References: Wang, L., He, L., Xie, M., Huang, J., Wang, C., Zhang, S., Yan, X., & Yuan, L. (2026). High-efficiency cellulosic biocatalysts constructed via Pichia pastoris surface display. AMB Express, 16(1), Article 104. https://doi.org/10.1186/s13568-026-02095-5

Image Credits: AI Generated

DOI: 10.1186/s13568-026-02095-5

Keywords: Pichia pastoris, cellulase, surface display, biocatalyst, biomass conversion, synthetic biology, enzyme engineering, recombinant yeast, High-efficiency, cellulosic, biocatalysts, constructed