Membrane curvature stress controls the maximal conversion of violaxanthin to zeaxanthin in the violaxanthin cycle - influence of alpha-tocopherol, cetylethers, linolenic acid, and temperature
(2007) In Biochimica et Biophysica Acta - Biomembranes 1768(9). p.2310-2318- Abstract
- Zeaxanthin, an important component in protection against overexcitation in higher plants, is formed from violaxanthin by the enzyme violaxanthin de-epoxidase. We have investigated factors that may control the maximal degree of conversion in the violaxanthin cycle. The conversion of violaxanthin to zeaxanthin in isolated spinach thylakoids was followed at different temperatures and in the presence of lipid packing modifiers. The maximum degree of conversion was found to be 35%, 70% and 80% at 4 'C, 25 'C and 37 'C respectively. In the presence of membrane modifying agents, known to promote non-lamellar structures (Hit), such as linolenic acid the conversion increased, and the maximal level of violaxanthin deepoxidation obtained was close to... (More)
- Zeaxanthin, an important component in protection against overexcitation in higher plants, is formed from violaxanthin by the enzyme violaxanthin de-epoxidase. We have investigated factors that may control the maximal degree of conversion in the violaxanthin cycle. The conversion of violaxanthin to zeaxanthin in isolated spinach thylakoids was followed at different temperatures and in the presence of lipid packing modifiers. The maximum degree of conversion was found to be 35%, 70% and 80% at 4 'C, 25 'C and 37 'C respectively. In the presence of membrane modifying agents, known to promote non-lamellar structures (Hit), such as linolenic acid the conversion increased, and the maximal level of violaxanthin deepoxidation obtained was close to 100%. In contrast, substances promoting lamellar phases (L.), such as alpha-tocopherol and 8-cetylether (C16EO8), only 55% and 35% of the violaxanthin was converted at 25 degrees C, respectively. The results are interpreted in light of the lipid composition of the thylakoid membrane, and we propose a model where a negative curvature elastic stress in the thylakoid lipid bilayer is required for violaxanthin deepoxidase activity. In this model zeaxanthin with its longer hydrophobic stretch is proposed to promote lamellar arrangements of the membrane. As a result, zeaxanthin relieves the curvature elastic stress, which in turn leads to inactivation of violaxanthin de-epoxidase. (c) 2007 Elsevier B.V. All rights reserved. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/655453
- author
- Szilagyi, Anna LU ; Sommarin, Marianne and Åkerlund, Hans-Erik LU
- organization
- publishing date
- 2007
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- zeaxanthin, violaxanthin de-epoxidase (VDE), membrane, thylakoid, membrane curvature stress, inverted hexagonal phase (H-II), xanthophyll cycle
- in
- Biochimica et Biophysica Acta - Biomembranes
- volume
- 1768
- issue
- 9
- pages
- 2310 - 2318
- publisher
- Elsevier
- external identifiers
-
- wos:000250040700030
- scopus:34548486245
- pmid:17618598
- ISSN
- 0005-2736
- DOI
- 10.1016/j.bbamem.2007.06.001
- language
- English
- LU publication?
- yes
- id
- 6c9020cb-e1aa-4f74-ab12-4158571791e0 (old id 655453)
- date added to LUP
- 2016-04-01 16:00:15
- date last changed
- 2022-01-28 08:38:51
@article{6c9020cb-e1aa-4f74-ab12-4158571791e0,
abstract = {{Zeaxanthin, an important component in protection against overexcitation in higher plants, is formed from violaxanthin by the enzyme violaxanthin de-epoxidase. We have investigated factors that may control the maximal degree of conversion in the violaxanthin cycle. The conversion of violaxanthin to zeaxanthin in isolated spinach thylakoids was followed at different temperatures and in the presence of lipid packing modifiers. The maximum degree of conversion was found to be 35%, 70% and 80% at 4 'C, 25 'C and 37 'C respectively. In the presence of membrane modifying agents, known to promote non-lamellar structures (Hit), such as linolenic acid the conversion increased, and the maximal level of violaxanthin deepoxidation obtained was close to 100%. In contrast, substances promoting lamellar phases (L.), such as alpha-tocopherol and 8-cetylether (C16EO8), only 55% and 35% of the violaxanthin was converted at 25 degrees C, respectively. The results are interpreted in light of the lipid composition of the thylakoid membrane, and we propose a model where a negative curvature elastic stress in the thylakoid lipid bilayer is required for violaxanthin deepoxidase activity. In this model zeaxanthin with its longer hydrophobic stretch is proposed to promote lamellar arrangements of the membrane. As a result, zeaxanthin relieves the curvature elastic stress, which in turn leads to inactivation of violaxanthin de-epoxidase. (c) 2007 Elsevier B.V. All rights reserved.}},
author = {{Szilagyi, Anna and Sommarin, Marianne and Åkerlund, Hans-Erik}},
issn = {{0005-2736}},
keywords = {{zeaxanthin; violaxanthin de-epoxidase (VDE); membrane; thylakoid; membrane curvature stress; inverted hexagonal phase (H-II); xanthophyll cycle}},
language = {{eng}},
number = {{9}},
pages = {{2310--2318}},
publisher = {{Elsevier}},
series = {{Biochimica et Biophysica Acta - Biomembranes}},
title = {{Membrane curvature stress controls the maximal conversion of violaxanthin to zeaxanthin in the violaxanthin cycle - influence of alpha-tocopherol, cetylethers, linolenic acid, and temperature}},
url = {{http://dx.doi.org/10.1016/j.bbamem.2007.06.001}},
doi = {{10.1016/j.bbamem.2007.06.001}},
volume = {{1768}},
year = {{2007}},
}