Dynamics at the protein-water interface from 17O spin relaxation in deeply supercooled solutions
(2008) In Biophysical Journal 95(6). p.2951-2963- Abstract
- Most of the decisive molecular events in biology take place at the protein-water interface. The dynamical properties of the hydration layer are therefore of fundamental importance. To characterize the dynamical heterogeneity and rotational activation energy in the hydration layer, we measured the 17O spin relaxation rate in dilute solutions of three proteins in a wide temperature range extending down to 238 K. We find that the rotational correlation time can be described by a power-law distribution with exponent 2.1 – 2.3. Except for a small fraction of secluded hydration sites, the dynamic perturbation in the hydration layer is the same for all proteins and does not differ in any essential way from the hydration shell of small organic... (More)
- Most of the decisive molecular events in biology take place at the protein-water interface. The dynamical properties of the hydration layer are therefore of fundamental importance. To characterize the dynamical heterogeneity and rotational activation energy in the hydration layer, we measured the 17O spin relaxation rate in dilute solutions of three proteins in a wide temperature range extending down to 238 K. We find that the rotational correlation time can be described by a power-law distribution with exponent 2.1 – 2.3. Except for a small fraction of secluded hydration sites, the dynamic perturbation in the hydration layer is the same for all proteins and does not differ in any essential way from the hydration shell of small organic solutes. In both cases, the dynamic perturbation factor is less than 2 at room temperature and exhibits a maximum near 260 K. This maximum implies that, at low temperatures, the rate of water molecule rotation has a weaker temperature dependence in the hydration layer than in bulk water. We attribute this difference to the temperature-independent constraints that the protein surface imposes on the water H-bond network. The free hydration layer studied here differs qualitatively from confined water in solid protein powder samples. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1227833
- author
- Mattea, Carlos LU ; Qvist, Johan LU and Halle, Bertil LU
- organization
- publishing date
- 2008
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biophysical Journal
- volume
- 95
- issue
- 6
- pages
- 2951 - 2963
- publisher
- Cell Press
- external identifiers
-
- wos:000258826900031
- scopus:55549086517
- pmid:18586840
- ISSN
- 1542-0086
- DOI
- 10.1529/biophysj.108.135194
- language
- English
- LU publication?
- yes
- id
- 7ed2e5e4-d2a2-4747-8ed9-c7d64b174be8 (old id 1227833)
- alternative location
- http://dx.doi.org/10.1529/biophysj.108.135194
- date added to LUP
- 2016-04-01 12:10:36
- date last changed
- 2022-03-28 21:18:30
@article{7ed2e5e4-d2a2-4747-8ed9-c7d64b174be8,
abstract = {{Most of the decisive molecular events in biology take place at the protein-water interface. The dynamical properties of the hydration layer are therefore of fundamental importance. To characterize the dynamical heterogeneity and rotational activation energy in the hydration layer, we measured the 17O spin relaxation rate in dilute solutions of three proteins in a wide temperature range extending down to 238 K. We find that the rotational correlation time can be described by a power-law distribution with exponent 2.1 – 2.3. Except for a small fraction of secluded hydration sites, the dynamic perturbation in the hydration layer is the same for all proteins and does not differ in any essential way from the hydration shell of small organic solutes. In both cases, the dynamic perturbation factor is less than 2 at room temperature and exhibits a maximum near 260 K. This maximum implies that, at low temperatures, the rate of water molecule rotation has a weaker temperature dependence in the hydration layer than in bulk water. We attribute this difference to the temperature-independent constraints that the protein surface imposes on the water H-bond network. The free hydration layer studied here differs qualitatively from confined water in solid protein powder samples.}},
author = {{Mattea, Carlos and Qvist, Johan and Halle, Bertil}},
issn = {{1542-0086}},
language = {{eng}},
number = {{6}},
pages = {{2951--2963}},
publisher = {{Cell Press}},
series = {{Biophysical Journal}},
title = {{Dynamics at the protein-water interface from 17O spin relaxation in deeply supercooled solutions}},
url = {{http://dx.doi.org/10.1529/biophysj.108.135194}},
doi = {{10.1529/biophysj.108.135194}},
volume = {{95}},
year = {{2008}},
}