Structure of Cellular Membranes and Regulation of Their Lipid Composition

摘要: Two lipid class substitution groups have been defined. Members of a group can replace each other in membranes. Similar are found for animal cells, fungi, and bacteria, although that occurs many organisms may be completely absent from others. Myelin is membrane has the maximum amount (fully packed) essentially all protein appears to bind polar lipid. Other membranes contain less more protein, some which does not appear In membranes, postulated lie upon it attached by apolar bonding carbon chains as well ionic hydrogen bonds through groups. Lipid molecules close interact their (apolar bonding). myelin, cholesterol probably binds acidic lipids. The level seen myelin human red blood cell one-half molar equals (acidic phospholipids, phosphatidyl ethanolamine, sulfatide, ganglioside). It thus two one cross section consist four layers sequence lipid-protein-lipid-lipid-protein-lipid. maximally packed with lipid, filled. lipid-binding incompletely cell, cover only about one-third surface. Membrane permeability substances related total those having most being least permeable. suggested blood-brain barrier exists because plasma cells nervous system than organs slowly penetrated substances. different compositions subcellular particulates same type correlated relative proportions types that, during differentiation, levels particulate set thereafter composition changes follow similar course organs. Some lipids abnormal states discussed.