Lipophosphonoglycan of the Plasma Membrane of Acanthamoeba castellanii

Approximately 14% of the mass of lipophosphonoglycan of the amoeba plasma membrane consists of three classes of long chain fatty acids: (a) normal, saturated and unsaturated and branched, saturated fatty acids C-16 to C-28, 4.5%; (b) normal and branched, saturated 2-hydroxy fatty acids C-22 to C-28, 8.4%; and (c) a group tentatively identified as normal and branched, saturated 2-hydroxy-3-methyl fatty acids, 0.9%. The branched fatty acids in the first two groups are tentatively identified as the anteiso series. Radioactive palmitic acid is incorporated by growing cells into the first two groups of fatty acids.