DHA-induced changes of supported lipid membrane morphology.
Docosahexaenoic acid (DHA) is a polyunsaturated long fatty acid known to have fundamental effects on cell membrane function. Here, the effect of DHA on phosphocholine-supported lipid bilayers was measured using the quartz crystal microbalance with dissipation monitoring (QCM-D) technique. Above a concentration of 60 muM (i.e., near the critical micelle concentration), DHA had drastic effects on the viscoelastic properties of the supported membranes, suggesting a more complex process and structure than simple insertion of molecules in the bilayer. Fluorescence microscopy revealed the spontaneous formation of elongated out-growths from the bilayers, which were remarkable for their length ( approximately 100 mum) and extensive coverage of the surface. These results demonstrate the applicability of QCM-D as a method to screen for conditions where membrane remodeling occurs but also that complementary techniques are required to describe in more detail the changes in viscoelastic properties of the membrane. These results are highly relevant for the present rapid development in the field of model lipid membranes aiming toward increased knowledge about processes occurring at biological surfaces.
Thid
Dorota
D
Department of Applied Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden. dorota.thid@chalmers.se
Benkoski
Jason J
JJ
Svedhem
Sofia
S
Kasemo
Bengt
B
Gold
Julie
J
D015374:Biosensing Techniques; D004281:Docosahexaenoic Acids / Q000737:chemistry / Q000494:pharmacology*; D066298:In Vitro Techniques; D008051:Lipid Bilayers / Q000737:chemistry; D008563:Membrane Lipids / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D010713:Phosphatidylcholines / Q000737:chemistry; D011791:Quartz; D013499:Surface Properties
D008051:Lipid Bilayers; D008563:Membrane Lipids; D010713:Phosphatidylcholines; D011791:Quartz; D004281:Docosahexaenoic Acids; C028694:1-palmitoyl-2-oleoylphosphatidylcholine