Probing Microscopic Orientation in Membranes by Linear Dichroism
Journal article, 2016

The cell, membrane is an ordered environment, which anisotropically affects the structure and interactions of all of its molecules. Monitoring membrane orientation at a local level is rather challenging but could reward crucial information on protein conformation and interactions, in the lipid bilayer. We monitored local, lipid ordering. changes upon varying the cholesterol concentration using polarized light spectroscopy and pyrene as a membrane probe., Pyrene, with, a shape intermediate between a disc and a rod, can detect microscopic orientation variations at the level of its site. The global membrane orientation was determined using curcumin, a probe with nonoverlapping absorption relative to that of pyrene. While the macroscopic orientation of a liquid-phase bilayer decreases with increasing cholesterol concentration, the local orientation is improved. Pyrene is,found to be sensitive to-the local effects induced by cholesterol and temperature on the bilayer. Disentangling local and global orientation effects in membranes could provide new insights into functionally significant interactions of membrane proteins.

pyrene

Materials Science

molecules

bilayers

spectroscopy

polarization

Chemistry

flow dichroism

curcumin

spectra

liposome

lipids

Author

Sandra Rocha

Chalmers, Biology and Biological Engineering, Chemical Biology

Maxim Kogan

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry, Physical Chemistry

Tamas Beke-Somfai

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry, Physical Chemistry

Bengt Nordén

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry, Physical Chemistry

Langmuir

07437463 (ISSN) 15205827 (eISSN)

Vol. 32 12 2841-2846

Subject Categories

Chemical Sciences

DOI

10.1021/acs.langmuir.5b04229

More information

Created

10/7/2017