Conformational Dynamics in the Core of Human Y145Stop Prion Protein Amyloid Probed by Relaxation Dispersion NMR.
Chemphyschem
; 20(2): 311-317, 2019 01 21.
Article
em En
| MEDLINE
| ID: mdl-30276945
ABSTRACT
Microsecond to millisecond timescale backbone dynamics of the amyloid core residues in Y145Stop human prion protein (PrP) fibrils were investigated by using 15 N rotating frame (R1ρ ) relaxation dispersion solid-state nuclear magnetic resonance spectroscopy over a wide range of spin-lock fields. Numerical simulations enabled the experimental relaxation dispersion profiles for most of the fibril core residues to be modelled by using a two-state exchange process with a common exchange rate of 1000â
s-1 , corresponding to protein backbone motion on the timescale of 1â
ms, and an excited-state population of 2 %. We also found that the relaxation dispersion profiles for several amino acids positioned near the edges of the most structured regions of the amyloid core were better modelled by assuming somewhat higher excited-state populations (â¼5-15 %) and faster exchange rate constants, corresponding to protein backbone motions on the timescale of â¼100-300â
µs. The slow backbone dynamics of the core residues were evaluated in the context of the structural model of human Y145Stop PrP amyloid.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Ressonância Magnética Nuclear Biomolecular
/
Proteínas Priônicas
/
Amiloide
Limite:
Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article