The University of Dublin | Trinity College -- Ollscoil Átha Cliath | Coláiste na Tríonóide
Trinity's Access to Research Archive
Home :: Log In :: Submit :: Alerts ::

TARA >
School of Biochemistry & Immunology >
Biochemistry >
Biochemistry (Scholarly Publications) >

Please use this identifier to cite or link to this item: http://hdl.handle.net/2262/50465

Title: Interactions of tryptophan, tryptophan peptides and tryptophan alkyl esters at curved membrane interfaces.
Author: CAFFREY, MARTIN
Author's Homepage: http://people.tcd.ie/mcaffre
Keywords: Biophysics
membrane proteins
crystallography
Issue Date: 2006
Publisher: American Chemical Society
Citation: Liu, W., Caffrey, M., Interactions of tryptophan, tryptophan peptides and tryptophan alkyl esters at curved membrane interfaces., Biochemistry, 45, 39, 2006, 11713-11726
Series/Report no.: Biochemistry;
45;
39;
Abstract: Motivated by on-going efforts to understand the mechanism of membrane protein crystallogenesis and transport in the lipidic cubic phase, the nature of the interaction between tryptophan and the bilayer/aqueous interface of the cubic phase has been investigated. The association was quantified by partitioning measurements which enabled the free energy of interaction to be determined. Temperature-dependent partitioning was used to parse the association free energy change into its enthalpic and entropic components. As has been observed with tryptophan derivatives interacting with glycerophospholipid bilayers in vesicles, tryptophan partitioning in the cubic phase is enthalpy driven. This is in contrast to partitioning into apolar solvents which exhibits the classic hydrophobic effect whose hallmark is a favorable entropy change. These results with tryptophan are somewhat surprising given the simplicity, homogeneity and curvature of the interface that prevails in the case of the cubic phase. Nevertheless, the interaction between tryptophan and the mesophase is very slight as revealed by its low partition coefficient. Additional evidence in support of interaction was obtained by electronic absorption and fluorescence spectroscopy and fluorescence quenching. Partitioning proved insensitive to the lipid composition of the membrane, examined by doping with glycerophospholipids. However, the interaction could be manipulated in meaningful ways by the inclusion in the aqueous medium of salt, glycerol or urea. The effects seen with tryptophan were amplified rationally when measurements were repeated using tryptophan alkyl esters and with tryptophan peptides of increasing length. These findings are interpreted in the context of the insertion, folding and function of proteins in membranes.
Description: PUBLISHED
URI: http://hdl.handle.net/2262/50465
Related links: http://dx.doi.org/10.1021/bi0608414
Appears in Collections:Biochemistry (Scholarly Publications)

Files in This Item:

File Description SizeFormat
Interactions.pdfPublished (author's copy) - Peer Reviewed1.86 MBAdobe PDFView/Open


This item is protected by original copyright


Please note: There is a known bug in some browsers that causes an error when a user tries to view large pdf file within the browser window. If you receive the message "The file is damaged and could not be repaired", please try one of the solutions linked below based on the browser you are using.

Items in TARA are protected by copyright, with all rights reserved, unless otherwise indicated.

 

Valid XHTML 1.0! DSpace Software Copyright © 2002-2010  Duraspace - Feedback