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Title: Proteins, fluctuations and complexity

Abstract

Glasses, supercooled liquids, and proteins share common properties, in particular the existence of two different types of fluctuations, {alpha} and {beta}. While the effect of the {alpha} fluctuations on proteins has been known for a few years, the effect of {beta} fluctuations has not been understood. By comparing neutron scattering data on the protein myoglobin with the {beta} fluctuations in the hydration shell measured by dielectric spectroscopy we show that the internal protein motions are slaved to these fluctuations. We also show that there is no 'dynamic transition' in proteins near 200 K. The rapid increase in the mean square displacement with temperature in many neutron scattering experiments is quantitatively predicted by the {beta} fluctuations in the hydration shell.

Authors:
 [1];  [1];  [1]
  1. Los Alamos National Laboratory
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
960459
Report Number(s):
LA-UR-08-04866; LA-UR-08-4866
TRN: US201006%%1129
DOE Contract Number:
AC52-06NA25396
Resource Type:
Journal Article
Resource Relation:
Journal Name: Philosophical Magazine
Country of Publication:
United States
Language:
English
Subject:
59; DIELECTRIC MATERIALS; FLUCTUATIONS; HYDRATION; LIQUIDS; MYOGLOBIN; NEUTRONS; PROTEINS; SCATTERING; SHELLS; SPECTROSCOPY

Citation Formats

Frauenfelder, Hans, Chen, Guo, and Fenimore, Paul W. Proteins, fluctuations and complexity. United States: N. p., 2008. Web.
Frauenfelder, Hans, Chen, Guo, & Fenimore, Paul W. Proteins, fluctuations and complexity. United States.
Frauenfelder, Hans, Chen, Guo, and Fenimore, Paul W. 2008. "Proteins, fluctuations and complexity". United States. doi:. https://www.osti.gov/servlets/purl/960459.
@article{osti_960459,
title = {Proteins, fluctuations and complexity},
author = {Frauenfelder, Hans and Chen, Guo and Fenimore, Paul W},
abstractNote = {Glasses, supercooled liquids, and proteins share common properties, in particular the existence of two different types of fluctuations, {alpha} and {beta}. While the effect of the {alpha} fluctuations on proteins has been known for a few years, the effect of {beta} fluctuations has not been understood. By comparing neutron scattering data on the protein myoglobin with the {beta} fluctuations in the hydration shell measured by dielectric spectroscopy we show that the internal protein motions are slaved to these fluctuations. We also show that there is no 'dynamic transition' in proteins near 200 K. The rapid increase in the mean square displacement with temperature in many neutron scattering experiments is quantitatively predicted by the {beta} fluctuations in the hydration shell.},
doi = {},
journal = {Philosophical Magazine},
number = ,
volume = ,
place = {United States},
year = 2008,
month = 1
}
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