Biology 2382B Lecture Notes - Lecture 13: Glycosylphosphatidylinositol, Peripheral Membrane Protein, Integral Membrane Protein
Document Summary
Structure, composition and properties of biological membranes: fatty acid properties and melting point, 4 properties of biomembranes. fluid, closed compartment, semi-permeable, asymmetric. Classes of membrane proteins. integral, lipid linked, peripheral. Insertion of membrane proteins types i, ii, iii, iv, tail anchored and gpi. Allow specialized functions to occur in a localized manner. Basic components: lipids, sterols, and proteins: biomembrane has lots of protein in it. Different from phospholipid bilayer formed in vitro. Long hydrocarbon chain attached to a polar carboxyl head group: polar head group can impart other functions to fatty acid. Often cx:y, where x = number of carbon molecules, y = number of double bonds. Unsaturated = one or more double bonds. More than one double bond = polyunsaturated. Melting point increases with increasing chain length: #c mp. Melting point decreases with increasing unsaturation: #double bonds mp. Fatty acids used as components of membrane lipids phospholipids, phosphoglycerides, sphingolipids etc (and sterols)