title: Lipid composition of plasma membranes isolated from light-grown barley (Hordeum vulgare) leaves: identification of cerebroside as a major component.
abstract: The total lipid composition of highly purified plasma membranes from light-grown barley (Hordeum vulgare) leaves was investigated. The plasma membranes were separated from intracellular membranes by subfractionation of the microsomal fraction using aqueous polymer two-phase partitioning. A novel finding was that glucocerebroside was a major lipid of the plasma membrane (23 mol%). The most abundant lipid class in the plasma membrane was phospholipid (42 mol%), consisting mainly of phosphatidylcholine and phosphatidylethanolamine, together with free sterols at a level of 28 mol%. The only free sterols of the plasma membrane were campesterol (15%), stigmasterol (23%), and sitosterol (62%). The plasma membrane contained a relatively high proportion of saturated fatty acids compared to the bulk of intracellular membranes, the major components of the plasma membrane being palmitic (16:0), linoleic (18:2), and linolenic (18:3) acids in approximately equal amounts.
mesh_terms: D002462:Cell Membrane / Q000378:metabolism; D002554:Cerebrosides / Q000302:isolation & purification / Q000378:metabolism*; D001467:Hordeum / Q000378:metabolism / Q000528:radiation effects; D008027:Light; D008563:Membrane Lipids / Q000302:isolation & purification / Q000378:metabolism*; D010743:Phospholipids / Q000302:isolation & purification / Q000378:metabolism; D010944:Plants / Q000378:metabolism* / Q000528:radiation effects
chemical_list: D002554:Cerebrosides; D008563:Membrane Lipids; D010743:Phospholipids