Heterogeneous Structure of Silk Fibers from Bombyx mori Resolved by 13C Solid-State NMR Spectroscopy

Citations Over TimeTop 10% of 2002 papers

Abstract

The molecular conformation of silk fibrion is characterized by solid-state 13C NMR before spinning (silk I structure) and after spinning (silk II structure). We compare native silk fibers with the quasi-crystalline Cp-fraction and a synthetic model peptide (Ala-Gly)15, both of which can be converted either into silk I by dialysis from 9 M LiBr or into silk II by treatment with formic acid. Our results demonstrate that silk II fibers are intrinsically heterogeneous, consisting of beta-sheets, distorted beta-turns, and distorted beta-sheets. This higher-order heterogeneity is revealed by the 13C-NMR Cbeta-peak of Ala, indicating that the Ala side chains are stacked partially in parallel and partially face-to-face, at a ratio of 1:2.

Related Papers

• → Effects of different Bombyx mori silkworm varieties on the structural characteristics and properties of silk(2015)84 cited
• → BmSuc1 Affects Silk Properties by Acting on Sericin1 in Bombyx mori(2022)9 cited
• → Discerning Silk Produced by Bombyx mori from Those Produced by Wild Species Using an Enzyme-Linked Immunosorbent Assay Combined with Conventional Methods(2017)35 cited
• → Comparison of Silks from Pseudoips prasinana and Bombyx mori Shows Molecular Convergence in Fibroin Heavy Chains but Large Differences in Other Silk Components(2021)19 cited
• → Hexosamine in Bombyx mori Silk(1965)3 cited