Solvent-Driven Dynamical Crossover in the Phenylalanine Side-Chain from the Hydrophobic Core of Amyloid Fibrils Detected by 2H NMR Relaxation
العنوان: | Solvent-Driven Dynamical Crossover in the Phenylalanine Side-Chain from the Hydrophobic Core of Amyloid Fibrils Detected by 2H NMR Relaxation |
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المؤلفون: | Wei Qiang, Liliya Vugmeyster, Gina L. Hoatson, Isaac B. Falconer, Dmitry Ostrovsky |
المصدر: | The Journal of Physical Chemistry B. 121:7267-7275 |
بيانات النشر: | American Chemical Society (ACS), 2017. |
سنة النشر: | 2017 |
مصطلحات موضوعية: | 0301 basic medicine, Work (thermodynamics), Chemistry, Crossover, Phenylalanine, Atmospheric temperature range, 010402 general chemistry, Fibril, Ring (chemistry), 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Solvent, 03 medical and health sciences, Crystallography, 030104 developmental biology, Materials Chemistry, Side chain, Physical and Theoretical Chemistry |
الوصف: | Aromatic residues are important markers of dynamical changes in proteins’ hydrophobic cores. In this work we investigated the dynamics of the F19 side-chain in the core of amyloid fibrils across a wide temperature range of 300 to 140 K. We utilized solid-state 2H NMR relaxation to demonstrate the presence of a solvent-driven dynamical crossover between different motional regimes, often also referred to as the dynamical transition. In particular, the dynamics are dominated by small-angle fluctuations at low temperatures and by π-flips of the aromatic ring at high temperatures. The crossover temperature is more than 43 degrees lower for the hydrated state of the fibrils compared to the dry state, indicating that interactions with water facilitate π-flips. Further, crossover temperatures are shown to be very sensitive to polymorphic states of the fibrils, such as the 2-fold and 3-fold symmetric morphologies of the wild-type protein as well as D23N mutant protofibrils. We speculate that these differences can ... |
تدمد: | 1520-5207 1520-6106 |
URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::e9c3f01aa7e5a2b905a0e4385afa05b8 https://doi.org/10.1021/acs.jpcb.7b04726 |
حقوق: | OPEN |
رقم الأكسشن: | edsair.doi...........e9c3f01aa7e5a2b905a0e4385afa05b8 |
قاعدة البيانات: | OpenAIRE |
تدمد: | 15205207 15206106 |
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