Ferritin-tagged ulva polysaccharide lyase for efficient degradation of biomass polysaccharides into reducing sugars

Enhancing the stability and the reusability of ulva polysaccharide lyase (UPL) is crucial for the efficient production of reducing sugars from ulva polysaccharides, which are vital for their broad applications in functional foods. In this study, we innovatively developed a self-immobilized UPL by fusing the enzyme with ferritin, leading to the spontaneous formation of micron-sized ulva polysaccharide lyase supraparticles (mUPLSPs). This novel system streamlines the enzyme purification and immobilization process into a single step, effectively circumventing the need for conventional, laborious chromatographic methods. The mUPLSPs exhibited superior stability and reusability, maintaining over 80% of their initial activity after five cycles of use. When compared to free UPLs, mUPLSPs displayed enhanced thermal and pH stability, resulting in a 252% increase in the yield of reducing sugars after a 40-hour reaction period. The ferritin-tagged, self-immobilization strategy not only provides a scalable and cost-efficient approach to the sustainable production of reducing sugars from ulva polysaccharides but also holds significant potential for industrial-scale applications.