Faculty Collaboration Database

Influence of lipid lateral distribution on the surface charge response of the phosphatidylcholine headgroup as detected using 2H nuclear magnetic resonance. Biochim Biophys Acta 1993 Mar 14;1146(2):219-28

Date

03/14/1993

Pubmed ID

8452858

DOI

10.1016/0005-2736(93)90359-8

Scopus ID

2-s2.0-0027400684 (requires institutional sign-in at Scopus site)   11 Citations

Abstract

The effect of lipid lateral distribution on the surface charge response of the phosphatidylcholine headgroup, in bilayers composed of binary mixtures of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1,2-dimyristoyl-sn-glycero-3-phosphate (DMPA), was investigated by monitoring the deuterium nuclear magnetic resonance (2H-NMR) spectrum of choline-deuterated phosphatidylcholine as a function of temperature and DMPA concentration. Addition of DMPA at temperatures corresponding to fully liquid-crystalline membranes caused a progressive increase (decrease) in the 2H-NMR quadrupole splitting from POPC-alpha-d2 (POPC-beta-d2), in agreement with the known response of phosphatidylcholine to negative membrane surface charge (Seelig, J., Macdonald, P.M. and Scherer, P.G. (1987) Biochemistry 26, 7535-7541). Lateral phase separation of DMPA-rich domains was induced in these mixtures by lowering the temperature in the range from 60 degrees C to -15 degrees C, and was accompanied by a reversal of the original effects of DMPA on the quadrupole splitting. Analysis of the 2H-NMR spectral response allows one to generate a temperature/composition phase diagram for the POPC/DMPA system. We conclude that 2H-NMR of headgroup-deuterated phosphatidylcholine can be employed to sense and to quantify inhomogeneities in the lateral distribution of charged membrane components.

Author List

Marassi FM, Djukic S, Macdonald PM

Author

Francesca M. Marassi PhD Chair, Professor in the Biophysics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aniline Compounds
Calorimetry, Differential Scanning
Deuterium
Magnetic Resonance Spectroscopy
Phosphatidylcholines
Temperature