Time Scales of Conformational Gating in a Lipid-Binding Protein
(2015) In The Journal of Physical Chemistry Part B 119(25). p.7957-7967- Abstract
- Lipid-binding proteins Sequester amphiphilic molecules in a large internal : cavity occupied by similar to 30 water molecules, some of which are displaced by the ligand. The role; of these internal water molecules in lipid binding and release is not understood. We use magnetic relaxation dispersion (MRD) to directly monitor internal-water dynamics in apo and palmitate-bound rat intestinal fatty acid-binding protein (rIFABP). Specifically, we record the water H-2 and O-17 MRD profiles of the apo and hobo forms of rIFABP in solution or immobilized by covalent cross-links. A global analysis of this extensive data set identifies three internal-water classes with mean survival times of similar to 1 ns, similar to 100 ns, and similar to 6 mu s.... (More)
- Lipid-binding proteins Sequester amphiphilic molecules in a large internal : cavity occupied by similar to 30 water molecules, some of which are displaced by the ligand. The role; of these internal water molecules in lipid binding and release is not understood. We use magnetic relaxation dispersion (MRD) to directly monitor internal-water dynamics in apo and palmitate-bound rat intestinal fatty acid-binding protein (rIFABP). Specifically, we record the water H-2 and O-17 MRD profiles of the apo and hobo forms of rIFABP in solution or immobilized by covalent cross-links. A global analysis of this extensive data set identifies three internal-water classes with mean survival times of similar to 1 ns, similar to 100 ns, and similar to 6 mu s. We associate the two longer time scales with conformational fluctuations of the gap between beta-strands D and E (similar to 6 mu s) and of the portal at the helix-capped end of the beta-barrel (similar to 100 ns). These fluctuations limit the exchange rates of a few highly ordered structural water molecules but not the dissociation rate of the fatty acid. The remaining 90% (apo) or 70% (hobo) of cavity waters exchange among internal hydration sites on a time scale of similar to 1 ns but exhibit substantial orientational order, particularly in the holo form. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/7791086
- author
- Kaieda, Shuji LU and Halle, Bertil LU
- organization
- publishing date
- 2015
- type
- Contribution to journal
- publication status
- published
- subject
- in
- The Journal of Physical Chemistry Part B
- volume
- 119
- issue
- 25
- pages
- 7957 - 7967
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000357139800018
- scopus:84933056912
- pmid:26012957
- ISSN
- 1520-5207
- DOI
- 10.1021/acs.jpcb.5b03214
- language
- English
- LU publication?
- yes
- id
- 5dcb397b-e0de-4018-967f-5bfd9b220093 (old id 7791086)
- date added to LUP
- 2016-04-01 13:21:54
- date last changed
- 2022-01-27 18:46:32
@article{5dcb397b-e0de-4018-967f-5bfd9b220093, abstract = {{Lipid-binding proteins Sequester amphiphilic molecules in a large internal : cavity occupied by similar to 30 water molecules, some of which are displaced by the ligand. The role; of these internal water molecules in lipid binding and release is not understood. We use magnetic relaxation dispersion (MRD) to directly monitor internal-water dynamics in apo and palmitate-bound rat intestinal fatty acid-binding protein (rIFABP). Specifically, we record the water H-2 and O-17 MRD profiles of the apo and hobo forms of rIFABP in solution or immobilized by covalent cross-links. A global analysis of this extensive data set identifies three internal-water classes with mean survival times of similar to 1 ns, similar to 100 ns, and similar to 6 mu s. We associate the two longer time scales with conformational fluctuations of the gap between beta-strands D and E (similar to 6 mu s) and of the portal at the helix-capped end of the beta-barrel (similar to 100 ns). These fluctuations limit the exchange rates of a few highly ordered structural water molecules but not the dissociation rate of the fatty acid. The remaining 90% (apo) or 70% (hobo) of cavity waters exchange among internal hydration sites on a time scale of similar to 1 ns but exhibit substantial orientational order, particularly in the holo form.}}, author = {{Kaieda, Shuji and Halle, Bertil}}, issn = {{1520-5207}}, language = {{eng}}, number = {{25}}, pages = {{7957--7967}}, publisher = {{The American Chemical Society (ACS)}}, series = {{The Journal of Physical Chemistry Part B}}, title = {{Time Scales of Conformational Gating in a Lipid-Binding Protein}}, url = {{http://dx.doi.org/10.1021/acs.jpcb.5b03214}}, doi = {{10.1021/acs.jpcb.5b03214}}, volume = {{119}}, year = {{2015}}, }