Pressure-induced protein unfolding in the ternary system AOT-octane-water is different from that in bulk water
(2005) In Langmuir 21(8). p.3599-3604- Abstract
- In a cellular environment, the presence of macromolecular cosolutes and membrane interfaces can influence the folding-unfolding behavior of proteins. Here we report on the pressure stability of alpha-chymotrypsin in the ternary system bis(2-ethylhexyl)sodium sulfosuccinate-octane-water using FTIR spectroscopy. The ternary system forms anionic reverse micelles which mimic cellular conditions. We find that inclusion of a single protein molecule in a reverse micelle does not alter its conformation. When pressurized in bulk water, alpha-chymotrypsin unfolds at 750 MPa into a partially unfolded structure. In contrast, in the ternary system, the same pressure increase induces a random coil-like unfolded state, which collapses into an amorphous... (More)
- In a cellular environment, the presence of macromolecular cosolutes and membrane interfaces can influence the folding-unfolding behavior of proteins. Here we report on the pressure stability of alpha-chymotrypsin in the ternary system bis(2-ethylhexyl)sodium sulfosuccinate-octane-water using FTIR spectroscopy. The ternary system forms anionic reverse micelles which mimic cellular conditions. We find that inclusion of a single protein molecule in a reverse micelle does not alter its conformation. When pressurized in bulk water, alpha-chymotrypsin unfolds at 750 MPa into a partially unfolded structure. In contrast, in the ternary system, the same pressure increase induces a random coil-like unfolded state, which collapses into an amorphous aggregate during the decompression phase. It is suggested that the unfolding pathway is different in a cell-mimicking environment due to the combined effect of multiple factors, including confinement. A phase transition of the reverse micellar to the lamellar phase is thought to be essential to provide the conditions required for unfolding and aggregation, though the unfolding is not a direct result of the phase transition. Our observations therefore suggest that membranes may cause the formation of alternative conformations that are more susceptible to aggregation. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/152263
- author
- Meersman, F ; Dirix, C ; Shipovskov, Stepan LU ; Klyachko, N L and Heremans, K
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Langmuir
- volume
- 21
- issue
- 8
- pages
- 3599 - 3604
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000228218700057
- pmid:15807607
- scopus:17444382363
- ISSN
- 0743-7463
- DOI
- 10.1021/la0470481
- language
- English
- LU publication?
- yes
- id
- 364049e3-d7a2-461b-8e2c-9c0f95ab96ee (old id 152263)
- date added to LUP
- 2016-04-01 12:14:59
- date last changed
- 2022-01-27 01:00:53
@article{364049e3-d7a2-461b-8e2c-9c0f95ab96ee,
abstract = {{In a cellular environment, the presence of macromolecular cosolutes and membrane interfaces can influence the folding-unfolding behavior of proteins. Here we report on the pressure stability of alpha-chymotrypsin in the ternary system bis(2-ethylhexyl)sodium sulfosuccinate-octane-water using FTIR spectroscopy. The ternary system forms anionic reverse micelles which mimic cellular conditions. We find that inclusion of a single protein molecule in a reverse micelle does not alter its conformation. When pressurized in bulk water, alpha-chymotrypsin unfolds at 750 MPa into a partially unfolded structure. In contrast, in the ternary system, the same pressure increase induces a random coil-like unfolded state, which collapses into an amorphous aggregate during the decompression phase. It is suggested that the unfolding pathway is different in a cell-mimicking environment due to the combined effect of multiple factors, including confinement. A phase transition of the reverse micellar to the lamellar phase is thought to be essential to provide the conditions required for unfolding and aggregation, though the unfolding is not a direct result of the phase transition. Our observations therefore suggest that membranes may cause the formation of alternative conformations that are more susceptible to aggregation.}},
author = {{Meersman, F and Dirix, C and Shipovskov, Stepan and Klyachko, N L and Heremans, K}},
issn = {{0743-7463}},
language = {{eng}},
number = {{8}},
pages = {{3599--3604}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Langmuir}},
title = {{Pressure-induced protein unfolding in the ternary system AOT-octane-water is different from that in bulk water}},
url = {{http://dx.doi.org/10.1021/la0470481}},
doi = {{10.1021/la0470481}},
volume = {{21}},
year = {{2005}},
}