Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

The role of protein hydrophobicity in thionin-phospholipid interactions : A comparison of α1 and α2-purothionin adsorbed anionic phospholipid monolayers

Clifton, Luke A. ; Sanders, Michael ; Kinane, Christian ; Arnold, Tom ; Edler, Karen J. LU orcid ; Neylon, Cameron ; Green, Rebecca J. and Frazier, Richard A. (2012) In Physical Chemistry Chemical Physics 14(39). p.13569-13579
Abstract

The plant defence proteins α1- and α2-purothionin (Pth) are type 1 thionins from common wheat (Triticum aestivum). These highly homologous proteins possess characteristics common amongst antimicrobial peptides and proteins, that is, cationic charge, amphiphilicity and hydrophobicity. Both α1- and α2-Pth possess the same net charge, but differ in relative hydrophobicity as determined by C18 reversed phase HPLC. Brewster angle microscopy, X-ray and neutron reflectometry, external reflection FTIR and associated surface pressure measurements demonstrated that α1 and α2-Pth interact strongly with condensed phase 1,2-dipalmitoyl-sn-glycero- 3-phospho-(1′-rac-glycerol) (DPPG) monolayers at the air/liquid interface. Both thionins disrupted the... (More)

The plant defence proteins α1- and α2-purothionin (Pth) are type 1 thionins from common wheat (Triticum aestivum). These highly homologous proteins possess characteristics common amongst antimicrobial peptides and proteins, that is, cationic charge, amphiphilicity and hydrophobicity. Both α1- and α2-Pth possess the same net charge, but differ in relative hydrophobicity as determined by C18 reversed phase HPLC. Brewster angle microscopy, X-ray and neutron reflectometry, external reflection FTIR and associated surface pressure measurements demonstrated that α1 and α2-Pth interact strongly with condensed phase 1,2-dipalmitoyl-sn-glycero- 3-phospho-(1′-rac-glycerol) (DPPG) monolayers at the air/liquid interface. Both thionins disrupted the in-plane structure of the anionic phospholipid monolayers, removing lipid during this process and both penetrated the lipid monolayer in addition to adsorbing as a single protein layer to the lipid head-group. However, analysis of the interfacial structures revealed that the α2-Pth showed faster disruption of the lipid film and removed more phospholipid (12%) from the interface than α1-Pth. Correlating the protein properties and lipid binding activity suggests that hydrophobicity plays a key role in the membrane lipid removal activity of thionins.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; and
publishing date
type
Contribution to journal
publication status
published
in
Physical Chemistry Chemical Physics
volume
14
issue
39
pages
11 pages
publisher
Royal Society of Chemistry
external identifiers
  • scopus:84866648692
  • pmid:22955734
ISSN
1463-9076
DOI
10.1039/c2cp42029e
language
English
LU publication?
no
id
6cb78213-775d-497e-96b0-8b3f1db2ff54
date added to LUP
2023-05-04 18:39:15
date last changed
2024-10-05 14:32:25
@article{6cb78213-775d-497e-96b0-8b3f1db2ff54,
  abstract     = {{<p>The plant defence proteins α1- and α2-purothionin (Pth) are type 1 thionins from common wheat (Triticum aestivum). These highly homologous proteins possess characteristics common amongst antimicrobial peptides and proteins, that is, cationic charge, amphiphilicity and hydrophobicity. Both α1- and α2-Pth possess the same net charge, but differ in relative hydrophobicity as determined by C18 reversed phase HPLC. Brewster angle microscopy, X-ray and neutron reflectometry, external reflection FTIR and associated surface pressure measurements demonstrated that α1 and α2-Pth interact strongly with condensed phase 1,2-dipalmitoyl-sn-glycero- 3-phospho-(1′-rac-glycerol) (DPPG) monolayers at the air/liquid interface. Both thionins disrupted the in-plane structure of the anionic phospholipid monolayers, removing lipid during this process and both penetrated the lipid monolayer in addition to adsorbing as a single protein layer to the lipid head-group. However, analysis of the interfacial structures revealed that the α2-Pth showed faster disruption of the lipid film and removed more phospholipid (12%) from the interface than α1-Pth. Correlating the protein properties and lipid binding activity suggests that hydrophobicity plays a key role in the membrane lipid removal activity of thionins.</p>}},
  author       = {{Clifton, Luke A. and Sanders, Michael and Kinane, Christian and Arnold, Tom and Edler, Karen J. and Neylon, Cameron and Green, Rebecca J. and Frazier, Richard A.}},
  issn         = {{1463-9076}},
  language     = {{eng}},
  month        = {{10}},
  number       = {{39}},
  pages        = {{13569--13579}},
  publisher    = {{Royal Society of Chemistry}},
  series       = {{Physical Chemistry Chemical Physics}},
  title        = {{The role of protein hydrophobicity in thionin-phospholipid interactions : A comparison of α1 and α2-purothionin adsorbed anionic phospholipid monolayers}},
  url          = {{http://dx.doi.org/10.1039/c2cp42029e}},
  doi          = {{10.1039/c2cp42029e}},
  volume       = {{14}},
  year         = {{2012}},
}