Structure remodeling of soy protein-derived amyloid fibrils mediated by epigallocatechin-3-gallate

Soy protein-derived amyloid fibrils (SAFs) held desirable features, and with rational tailoring of physical structures, their techno-functions could be further improved. Here, we report a strategy for tailoring SAFs to form hydrogels with appealing mechanical properties as mediated by (-)-epigallocatechin-3-gallate (EGCG). The SAFs-EGCG complexes are characterized by measuring changes in gelling properties, identifying interfacing residues, and understanding the molecular geometry of complexes. EGCG is found to cleave rigid SAFs and induce the formation of large branched chains, which are essential for forming gel-like structures. Results in this study show that SAFs-EGCG complexes and their digesta are non-toxic in human cell lines, and these complexes are superior in inhibiting the growth of Escherichia coli and Staphylococcus aureus. This study provides new insights into remodeling structures and steering techno-functions of SAFs through interaction with EGCG, and will serve as a basis for EGCG as a potent remodeling agent of food protein-derived fibrils.