Bilayers of dipalmitoyl-3-sn-phosphatidylcholine. Conformational differences between the fatty acyl chains.
Dipalmitoyl-3-sn-phosphatidylcholine is specifically deuterated at the C-2 position of the fatty acyl chains. Using deuterium magnetic resonance it is then possible to probe the chain conformation in the vicinity of the polar head groups. Three separate quadrupole splittings are observed for bilayers of 1,2[2'-2H2]palmitoyl-3-sn-phosphatidylcholine, indicating that the two chains behave differently. The synthesis of phosphatidylcholines each deuterated in only one chain allows the assignment of the three resonances. It is concluded that the beginnings of the two chains have orientations parallel and perpendicular to the bilayer normal. The data further suggest the possibility of two long-lived conformations of the glycerol constituent.
D001665:Binding Sites; D009682:Magnetic Resonance Spectroscopy; D008567:Membranes, Artificial; D008954:Models, Biological; D008968:Molecular Conformation; D010169:Palmitic Acids; D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D013696:Temperature
D008567:Membranes, Artificial; D010169:Palmitic Acids; D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants