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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ftunivzuerich:oai:www.zora.uzh.ch:64643 2024-06-23T07:56:58+00:00 Temperature dependence of the heat diffusivity of proteins Helbing, Jan Devereux, Michael Nienhaus, Karin Nienhaus, G Ulrich Hamm, Peter Meuwly, Markus 2012 application/pdf https://www.zora.uzh.ch/id/eprint/64643/ https://www.zora.uzh.ch/id/eprint/64643/1/postprintHelbing_JPhysChemA_2012.pdf https://doi.org/10.5167/uzh-64643 https://doi.org/10.1021/jp2061877 eng eng American Chemical Society https://www.zora.uzh.ch/id/eprint/64643/1/postprintHelbing_JPhysChemA_2012.pdf doi:10.5167/uzh-64643 doi:10.1021/jp2061877 info:pmid/22047554 urn:issn:1089-5639 info:eu-repo/semantics/openAccess Helbing, Jan; Devereux, Michael; Nienhaus, Karin; Nienhaus, G Ulrich; Hamm, Peter; Meuwly, Markus (2012). Temperature dependence of the heat diffusivity of proteins. Journal of Physical Chemistry A, 116(11):2620-2628. Department of Chemistry 540 Chemistry Journal Article PeerReviewed info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion 2012 ftunivzuerich https://doi.org/10.5167/uzh-6464310.1021/jp2061877 2024-06-12T00:23:53Z 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 Zurich (UZH): ZORA (Zurich Open Repository and Archive |
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Open Polar |
collection |
University of Zurich (UZH): ZORA (Zurich Open Repository and Archive |
op_collection_id |
ftunivzuerich |
language |
English |
topic |
Department of Chemistry 540 Chemistry |
spellingShingle |
Department of Chemistry 540 Chemistry Helbing, Jan Devereux, Michael Nienhaus, Karin Nienhaus, G Ulrich Hamm, Peter Meuwly, Markus Temperature dependence of the heat diffusivity of proteins |
topic_facet |
Department of Chemistry 540 Chemistry |
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 |
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 |
2012 |
url |
https://www.zora.uzh.ch/id/eprint/64643/ https://www.zora.uzh.ch/id/eprint/64643/1/postprintHelbing_JPhysChemA_2012.pdf https://doi.org/10.5167/uzh-64643 https://doi.org/10.1021/jp2061877 |
genre |
Sperm whale |
genre_facet |
Sperm whale |
op_source |
Helbing, Jan; Devereux, Michael; Nienhaus, Karin; Nienhaus, G Ulrich; Hamm, Peter; Meuwly, Markus (2012). Temperature dependence of the heat diffusivity of proteins. Journal of Physical Chemistry A, 116(11):2620-2628. |
op_relation |
https://www.zora.uzh.ch/id/eprint/64643/1/postprintHelbing_JPhysChemA_2012.pdf doi:10.5167/uzh-64643 doi:10.1021/jp2061877 info:pmid/22047554 urn:issn:1089-5639 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5167/uzh-6464310.1021/jp2061877 |
_version_ |
1802650393191120896 |