Structure of an Adsorbed Dimyristoylphosphatidylcholine Bilayer Measured with Specular Reflection of Neutrons
Overview
Affiliations
Using specular reflection of neutrons, we investigate for the first time the structure of a single dimyristoylphosphatidylcholine bilayer adsorbed to a planar quartz surface in an aqueous environment. We demonstrate that the bilayer is strongly adsorbed to the quartz surface and is stable to phase state changes as well as exchange of the bulk aqueous phase. Our results show that the main phase transition is between the L alpha phase and the metastable L beta'* phase, with formation of the P beta' ripple phase prevented by lateral stress on the adsorbed bilayer. By performing contrast variation experiments, we are able to elucidate substantial detail in the interfacial structure. We measure a bilayer thickness of 43.0 +/- 1.5 A in the L alpha phase (T = 31 degrees C) and 46.0 +/- 1.5 A in the L beta'* phase (T = 20 degrees C). The polar head group is 8.0 +/- 1.5 A thick in the L alpha phase. The water layer between the quartz and bilayer is 30 +/- 10 A for the lipid in both the L alpha and L'* phase. Our results agree well with those previously reported from experiments using lipid vesicles and monolayers, thus establishing the feasibility of our experimental methods.
Juhaniewicz-Debinska J Molecules. 2025; 29(24.
PMID: 39770152 PMC: 11677270. DOI: 10.3390/molecules29246064.
CHARMM-GUI Multicomponent Assembler for modeling and simulation of complex multicomponent systems.
Kern N, Lee J, Choi Y, Im W Nat Commun. 2024; 15(1):5459.
PMID: 38937468 PMC: 11211406. DOI: 10.1038/s41467-024-49700-4.
Forces and Flows at Cell Surfaces.
Honerkamp-Smith A J Membr Biol. 2023; 256(4-6):331-340.
PMID: 37773346 PMC: 10947748. DOI: 10.1007/s00232-023-00293-x.
Fluorophore position of headgroup-labeled Gb glycosphingolipids in lipid bilayers.
Socrier L, Sharma A, Chen T, Flato K, Kettelhoit K, Enderlein J Biophys J. 2023; 122(20):4104-4112.
PMID: 37735870 PMC: 10598288. DOI: 10.1016/j.bpj.2023.09.010.
Le Brun A, Huang T, Pullen S, Nelson A, Spedding J, Holt S J Appl Crystallogr. 2023; 56(Pt 1):18-25.
PMID: 36777140 PMC: 9901927. DOI: 10.1107/S160057672201086X.