The chaperone-like activity of a small heat shock protein is lost after sulfoxidation of conserved methionines in a surface-exposed amphipathic α-helix
(2001) In BBA - Protein Structure and Molecular Enzymology 1545(1-2). p.227-237- Abstract
- The small heat shock proteins (sHsps) possess a chaperone-like activity which prevents aggregation of other proteins during transient heat or oxidative stress. The sHsps bind, onto their surface, molten globule forms of other proteins, thereby keeping them in a refolding competent state. In Hsp21, a chloroplast-located sHsp in all higher plants, there is a highly conserved region forming an amphipathic α-helix with several methionines on the hydrophobic side according to secondary structure prediction. This paper describes how sulfoxidation of the methionines in this amphipathic α-helix caused conformational changes and a reduction in the Hsp21 oligomer size, and a complete loss of the chaperone-like activity. Concomitantly, there was a... (More)
- The small heat shock proteins (sHsps) possess a chaperone-like activity which prevents aggregation of other proteins during transient heat or oxidative stress. The sHsps bind, onto their surface, molten globule forms of other proteins, thereby keeping them in a refolding competent state. In Hsp21, a chloroplast-located sHsp in all higher plants, there is a highly conserved region forming an amphipathic α-helix with several methionines on the hydrophobic side according to secondary structure prediction. This paper describes how sulfoxidation of the methionines in this amphipathic α-helix caused conformational changes and a reduction in the Hsp21 oligomer size, and a complete loss of the chaperone-like activity. Concomitantly, there was a loss of an outer-surface located α-helix as determined by limited proteolysis and circular dichroism spectroscopy. The present data indicate that the methionine-rich amphipathic α-helix, a motif of unknown physiological significance which evolved during the land plant evolution, is crucial for binding of substrate proteins and has rendered the chaperone-like activity of Hsp21 very dependent on the chloroplast redox state. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/125008
- author
- Härndahl, Ulrika ; Kokke, Bas P.A. ; Gustavsson, Niklas LU ; Linse, Sara LU ; Berggren, Kristina ; Tjerneld, Folke LU ; Boelens, Wilbert C. and Sundby, Cecilia
- organization
- publishing date
- 2001
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Small heat shock protein, Methionine sulfoxidation, Chaperone, Oligomer, Amphipathic α-helix
- in
- BBA - Protein Structure and Molecular Enzymology
- volume
- 1545
- issue
- 1-2
- pages
- 227 - 237
- publisher
- Elsevier
- external identifiers
-
- scopus:0035830637
- ISSN
- 0167-4838
- DOI
- 10.1016/S0167-4838(00)00280-6
- language
- English
- LU publication?
- yes
- id
- 3627fcb8-4d59-47a9-b3f8-c00a9c502479 (old id 125008)
- date added to LUP
- 2016-04-01 15:52:13
- date last changed
- 2022-01-28 07:38:49
@article{3627fcb8-4d59-47a9-b3f8-c00a9c502479, abstract = {{The small heat shock proteins (sHsps) possess a chaperone-like activity which prevents aggregation of other proteins during transient heat or oxidative stress. The sHsps bind, onto their surface, molten globule forms of other proteins, thereby keeping them in a refolding competent state. In Hsp21, a chloroplast-located sHsp in all higher plants, there is a highly conserved region forming an amphipathic α-helix with several methionines on the hydrophobic side according to secondary structure prediction. This paper describes how sulfoxidation of the methionines in this amphipathic α-helix caused conformational changes and a reduction in the Hsp21 oligomer size, and a complete loss of the chaperone-like activity. Concomitantly, there was a loss of an outer-surface located α-helix as determined by limited proteolysis and circular dichroism spectroscopy. The present data indicate that the methionine-rich amphipathic α-helix, a motif of unknown physiological significance which evolved during the land plant evolution, is crucial for binding of substrate proteins and has rendered the chaperone-like activity of Hsp21 very dependent on the chloroplast redox state.}}, author = {{Härndahl, Ulrika and Kokke, Bas P.A. and Gustavsson, Niklas and Linse, Sara and Berggren, Kristina and Tjerneld, Folke and Boelens, Wilbert C. and Sundby, Cecilia}}, issn = {{0167-4838}}, keywords = {{Small heat shock protein; Methionine sulfoxidation; Chaperone; Oligomer; Amphipathic α-helix}}, language = {{eng}}, number = {{1-2}}, pages = {{227--237}}, publisher = {{Elsevier}}, series = {{BBA - Protein Structure and Molecular Enzymology}}, title = {{The chaperone-like activity of a small heat shock protein is lost after sulfoxidation of conserved methionines in a surface-exposed amphipathic α-helix}}, url = {{http://dx.doi.org/10.1016/S0167-4838(00)00280-6}}, doi = {{10.1016/S0167-4838(00)00280-6}}, volume = {{1545}}, year = {{2001}}, }