Structural characterisation of amyloid-like fibrils formed by an amyloidogenic peptide segment of β-lactoglobulinShow others and affiliations
2021 (English)In: RSC Advances, E-ISSN 2046-2069, Vol. 11, no 45, p. 27868-27879Article in journal (Refereed) Published
Abstract [en]
Protein nanofibrils (PNFs) represent a promising class of biobased nanomaterials for biomedical and materials science applications. In the design of such materials, a fundamental understanding of the structure–function relationship at both molecular and nanoscale levels is essential. Here we report investigations of the nanoscale morphology and molecular arrangement of amyloid-like PNFs of a synthetic peptide fragment consisting of residues 11–20 of the protein β-lactoglobulin (β-LG11–20), an important model system for PNF materials. Nanoscale fibril morphology was analysed by atomic force microscopy (AFM) that indicates the presence of polymorphic self-assembly of protofilaments. However, observation of a single set of 13C and 15N resonances in the solid-state NMR spectra for the β-LG11–20 fibrils suggests that the observed polymorphism originates from the assembly of protofilaments at the nanoscale but not from the molecular structure. The secondary structure and inter-residue proximities in the β-LG11–20 fibrils were probed using NMR experiments of the peptide with 13C- and 15N-labelled amino acid residues at selected positions. We can conclude that the peptides form parallel β-sheets, but the NMR data was inconclusive regarding inter-sheet packing. Molecular dynamics simulations confirm the stability of parallel β-sheets and suggest two preferred modes of packing. Comparison of molecular dynamics models with NMR data and calculated chemical shifts indicates that both packing models are possible.
Place, publisher, year, edition, pages
Royal Society of Chemistry, 2021. Vol. 11, no 45, p. 27868-27879
National Category
Physical Chemistry
Research subject
Chemistry of Interfaces
Identifiers
URN: urn:nbn:se:ltu:diva-87127DOI: 10.1039/d1ra03575dISI: 000694655300013PubMedID: 35480736Scopus ID: 2-s2.0-85114733485OAI: oai:DiVA.org:ltu-87127DiVA, id: diva2:1595525
Funder
Carl Tryggers foundation , CTS16:273; CTS18:810The Kempe FoundationsSwedish e‐Science Research CenterSwedish National Infrastructure for Computing (SNIC)
Note
Validerad;2021;Nivå 2;2021-09-20 (beamah)
2021-09-202021-09-202023-09-05Bibliographically approved