Temperature Dependence of the Heat Diffusivity of Proteins
In a combined experimental–theoretical study, we investigated the transport of vibrational energy from the surrounding solvent into the interior of a heme protein, the sperm whale myoglobin double mutant L29W-S108L, and its dependence on temperature from 20 to 70 K. The hindered libration of a CO mo...
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American Chemical Society
2011
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ftunivbasel:oai:edoc.unibas.ch:22200 2023-05-15T18:26:46+02:00 Temperature Dependence of the Heat Diffusivity of Proteins Helbing, Jan Devereux, Michael Nienhaus, Karin Nienhaus, G. Ulrich Hamm, Peter Meuwly, Markus 2011 http://edoc.unibas.ch/dok/A6002063 https://edoc.unibas.ch/22200/ https://doi.org/10.1021/jp2061877 unknown American Chemical Society Helbing, Jan and Devereux, Michael and Nienhaus, Karin and Nienhaus, G. Ulrich and Hamm, Peter and Meuwly, Markus. (2011) Temperature Dependence of the Heat Diffusivity of Proteins. The Journal of Physical Chemistry A, 116 (11). pp. 2620-2628. doi:10.1021/jp2061877 info:isi/000301766500004 urn:ISSN:1089-5639 urn:ISSN:1520-5215 info:eu-repo/semantics/closedAccess Article PeerReviewed 2011 ftunivbasel https://doi.org/10.1021/jp2061877 2023-03-05T06:57:58Z In a combined experimental–theoretical study, we investigated the transport of vibrational energy from the surrounding solvent into the interior of a heme protein, the sperm whale myoglobin double mutant L29W-S108L, and its dependence on temperature from 20 to 70 K. The hindered libration of a CO molecule that is not covalently bound to any part of the protein but is trapped in one of its binding pockets (the Xe4 pocket) was used as the local thermometer. Energy was deposited into the solvent by IR excitation. Experimentally, the energy transfer rate increased from (30 ps)−1 at 20 K to (8 ps)−1 at 70 K. This temperature trend is opposite to what is expected, assuming that the mechanism of heat transport is similar to that in glasses. In order to elucidate the mechanism and its temperature dependence, nonequilibrium molecular dynamics (MD) simulations were performed, which, however, predicted an essentially temperature-independent rate of vibrational energy flow. We tentatively conclude that the MD potentials overestimate the coupling between the protein and the CO molecule, which appears to be the rate-limiting step in the real system at low temperatures. Assuming that this coupling is anharmonic in nature, the observed temperature trend can readily be explained. Article in Journal/Newspaper Sperm whale University of Basel: edoc The Journal of Physical Chemistry A 116 11 2620 2628 |
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University of Basel: edoc |
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ftunivbasel |
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description |
In a combined experimental–theoretical study, we investigated the transport of vibrational energy from the surrounding solvent into the interior of a heme protein, the sperm whale myoglobin double mutant L29W-S108L, and its dependence on temperature from 20 to 70 K. The hindered libration of a CO molecule that is not covalently bound to any part of the protein but is trapped in one of its binding pockets (the Xe4 pocket) was used as the local thermometer. Energy was deposited into the solvent by IR excitation. Experimentally, the energy transfer rate increased from (30 ps)−1 at 20 K to (8 ps)−1 at 70 K. This temperature trend is opposite to what is expected, assuming that the mechanism of heat transport is similar to that in glasses. In order to elucidate the mechanism and its temperature dependence, nonequilibrium molecular dynamics (MD) simulations were performed, which, however, predicted an essentially temperature-independent rate of vibrational energy flow. We tentatively conclude that the MD potentials overestimate the coupling between the protein and the CO molecule, which appears to be the rate-limiting step in the real system at low temperatures. Assuming that this coupling is anharmonic in nature, the observed temperature trend can readily be explained. |
format |
Article in Journal/Newspaper |
author |
Helbing, Jan Devereux, Michael Nienhaus, Karin Nienhaus, G. Ulrich Hamm, Peter Meuwly, Markus |
spellingShingle |
Helbing, Jan Devereux, Michael Nienhaus, Karin Nienhaus, G. Ulrich Hamm, Peter Meuwly, Markus Temperature Dependence of the Heat Diffusivity of Proteins |
author_facet |
Helbing, Jan Devereux, Michael Nienhaus, Karin Nienhaus, G. Ulrich Hamm, Peter Meuwly, Markus |
author_sort |
Helbing, Jan |
title |
Temperature Dependence of the Heat Diffusivity of Proteins |
title_short |
Temperature Dependence of the Heat Diffusivity of Proteins |
title_full |
Temperature Dependence of the Heat Diffusivity of Proteins |
title_fullStr |
Temperature Dependence of the Heat Diffusivity of Proteins |
title_full_unstemmed |
Temperature Dependence of the Heat Diffusivity of Proteins |
title_sort |
temperature dependence of the heat diffusivity of proteins |
publisher |
American Chemical Society |
publishDate |
2011 |
url |
http://edoc.unibas.ch/dok/A6002063 https://edoc.unibas.ch/22200/ https://doi.org/10.1021/jp2061877 |
genre |
Sperm whale |
genre_facet |
Sperm whale |
op_relation |
Helbing, Jan and Devereux, Michael and Nienhaus, Karin and Nienhaus, G. Ulrich and Hamm, Peter and Meuwly, Markus. (2011) Temperature Dependence of the Heat Diffusivity of Proteins. The Journal of Physical Chemistry A, 116 (11). pp. 2620-2628. doi:10.1021/jp2061877 info:isi/000301766500004 urn:ISSN:1089-5639 urn:ISSN:1520-5215 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1021/jp2061877 |
container_title |
The Journal of Physical Chemistry A |
container_volume |
116 |
container_issue |
11 |
container_start_page |
2620 |
op_container_end_page |
2628 |
_version_ |
1766208735067242496 |