Format

Send to

Choose Destination
See comment in PubMed Commons below
Biophys Chem. 2011 Dec;159(2-3):321-7. doi: 10.1016/j.bpc.2011.08.005. Epub 2011 Aug 27.

Interaction of a two-transmembrane-helix peptide with lipid bilayers and dodecyl sulfate micelles.

Author information

1
Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA. Robert.Renthal@UTSA.edu

Abstract

To probe structural changes that occur when a membrane protein is transferred from lipid bilayers to SDS micelles, a fragment of bacteriorhodopsin containing transmembrane helical segments A and B was studied by fluorescence spectroscopy, molecular dynamics (MD) simulation, and stopped flow kinetics. In lipid bilayers, Förster resonance energy transfer (FRET) was observed between tyrosine 57 on helix B and tryptophans 10 and 12 on helix A. FRET efficiency decreased substantially when the peptide was transferred to SDS. MD simulation showed no evidence for significant disruption of helix-helix interactions in SDS micelles. However, a cluster of water molecules was observed to form a hydrogen-bonded network with the phenolic hydroxyl group of tyrosine 57, which probably causes the disappearance of tyrosine-to-tryptophan FRET in SDS. The tryptophan quantum yield decreased in SDS, and the change occurred at nearly the same rate as membrane solubilization. The results provide a clear example of the importance of corroborating distance changes inferred from FRET by using complementary methods.

PMID:
21924540
PMCID:
PMC3192009
DOI:
10.1016/j.bpc.2011.08.005
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center