Laurent, H orcid.org/0000-0002-8925-4773, Soper, AK orcid.org/0000-0002-7903-8356 and Dougan, L orcid.org/0000-0002-2620-5827 (2020) Trimethylamine N-oxide (TMAO) resists the compression of water structure by magnesium perchlorate: terrestrial kosmotrope vs. Martian chaotrope. Physical Chemistry Chemical Physics, 22 (9). pp. 4924-4937. ISSN 1463-9076
Abstract
The presence of magnesium perchlorate (Mg(ClO4)2) as the dominant ionic compound in the Martian regolith and the recent discovery of a subsurface lake on Mars suggests that beneath the Martian surface may lie an aqueous environment suitable for life, rich in chaotropic ions. Closer to Earth, terrestrial organisms use osmolytes, such as trimethylamine N-oxide (TMAO), to overcome the biologically damaging effects of pressure. While previous studies have revealed that Mg(ClO4)2 acts to modify water structure as if it has been pressurized, little is known about the competing effects of chaotropes and kosmotropes. Here we ask whether TMAO can help to preserve the hydrogen bond network of water against the pressurising effect of Mg(ClO4)2? We address this question using neutron scattering, computational modelling using Empirical Potential Structure Refinement (EPSR) analysis, and a new approach to quantifying hydrogen bond conformations and energies. We find that the addition of 1.0 M TMAO to 0.2 M Mg(ClO4)2 or to 2.7 M Mg(ClO4)2 is capable of partially restoring the hydrogen bond network of water, and the fraction of water molecules in energetically unfavourable conformations. This suggests that terrestrial protecting osmolytes could provide a protective mechanism to the extremes found in Martian environments for biological systems.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © the Owner Societies 2020. This is an author produced version of an article published in Physical Chemistry Chemical Physics. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Molecular & Nanoscale Physics |
Depositing User: | Symplectic Publications |
Date Deposited: | 20 Apr 2020 09:26 |
Last Modified: | 20 Dec 2024 11:22 |
Status: | Published |
Publisher: | Royal Society of Chemistry (RSC) |
Identification Number: | 10.1039/c9cp06324b |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:159569 |