Effect of membrane composition on surface states of ganglioside GM1/dipalmitoylphosphatidylcholine/dioleoylphosphatidylcholine monolayers.
The surface states of ganglioside GM1 (GM1)/dipalmitoylphosphatidylcholine (DPPC)/dioleoylphosphatidylcholine (DOPC) monolayers having various compositions were investigated using atomic force microscopy (AFM), and the effect of the composition on the surface states of the membrane was examined. The AFM images for the ternary system showed a DPPC-rich phase containing GM1 in the DOPC matrix, which indicated that the morphology varied as the composition of the monolayers changed. The AFM images for the GM1/DPPC/DOPC monolayers having (2:9:9) and (4:18:9) molar ratios showed a percolation pattern similar to that observed for the GM1/DPPC (1:9) monolayer. The AFM image for the GM1/DPPC/DOPC (2:18:9) monolayer showed a dotted pattern with a high topography. Monolayers having a higher content of DOPC than DPPC and/or having a higher content of GM1 showed dot-like domains in the DPPC-rich phase containing GM1. In conclusion, the surface states of GM1/DPPC/DOPC monolayers changed depending on the composition. These results may be related to a diversity of GM1 in various organs.
Yokoyama
Shoko
S
School of Pharmaceutical Sciences, Kyushu University of Health and Welfare, 1714-1 Yoshino-cho, Nobeoka-city, Miyazaki 882-8508, Japan. s.yokoyama@phoenix.ac.jp
Ohta
Yumiko
Y
Sakai
Hideki
H
Abe
Masahiko
M
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D002462:Cell Membrane / Q000378:metabolism; D005677:G(M1) Ganglioside / Q000737:chemistry*; D008051:Lipid Bilayers / Q000378:metabolism; D008563:Membrane Lipids / Q000737:chemistry; D008566:Membranes / Q000378:metabolism; D018625:Microscopy, Atomic Force; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry*; D013499:Surface Properties
D008051:Lipid Bilayers; D008563:Membrane Lipids; D010713:Phosphatidylcholines; D015060:1,2-Dipalmitoylphosphatidylcholine; D005677:G(M1) Ganglioside; C017251:1,2-oleoylphosphatidylcholine