Formation and structural characteristics of pea globulin amyloid-like fibrils pretreated with low-frequency magnetic field

Abstract

In this study, the effect of low-frequency magnetic field (LF-MF) on the formation and structural characteristics of pea globulin (PG) amyloid-like fibrils were investigated. The results showed that the structure of PG unfolded after LF-MF pretreatment. And PG pretreated with LF-MF (MPG) exhibited higher thioflavin T fluorescence intensity during the fibrillation compared with native PG (NPG), indicating that LF-MF could enhance the ability of PG to form amyloid-like fibrils. During the fibrillation process, the PG was hydrolyzed into small peptides in the initial stage of heating, leading to decreased particle size, as evidenced by the degraded subunits. The average particle size then increased with the small peptides aggregating, and the ordered amyloid-like fibrils with high content of β-sheets were formed. But the fibrils generated by MPG were larger in size and had a higher content of β-sheets. The formation of PG amyloid-like fibrils was confirmed by AFM images, and LF-MF pretreatment resulted in the generation of longer and thicker PG fibrils. The results of surface hydrophobicity showed that the hydrophobic interactions played an important role in the fibrillation process of PG. This work may provide a deep understanding about the effect of LF-MF on the assembly behavior and structural characteristics of PG amyloid-like fibrils.