PH-controlled stacking direction of the β-strands in peptide fibrils.

ABSTRACT: Peptides provide a framework for generating functional biopolymers. In this study, the pH-dependent structural changes in the 21-29 fragment peptide of β₂-microglobulin (β₂m_21-29) during self-aggregation, i.e., the formation of an amyloid fibril, were discussed. The β-sheet structures formed during parallel stacking under basic conditions (pH ≥ 7.7) adopted an anti-parallel stacking configuration under acidic conditions (pH ≤ 7.6). The parallel and anti-parallel β-sheets existed separately at the intermediate pH (pH = 7.6-7.7). These results were attributed to the rigidity of the β-sheets in the fibrils, which prevented the stable hydrogen bonding interactions between the parallel and anti-parallel β-sheet moieties. This observed pH dependence was ascribed

SUBMITTER: Tseng WH 

PROVIDER: S-EPMC7747703 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature