Biology 2382B Lecture Notes - Isoprene, Partition Coefficient, Translocon
Document Summary
Three types of membrane proteins: integral, lipid-linked, peripheral. The predicted length of such an alpha helix is just sufficient to span the hydrocarbon core of the bilayer. The helices in many cells are perpendicular to the bilayer, but in some the helices transverse the membrane at an oblique angle. Lipid-anchored membrane proteins bound covalently to one or more lipid molecules. The hydrophobic segment of the attached lipid is embedded in one leaflet of the membrane and anchors the protein to the membrane. The polypeptide chain itself doesn"t enter the bilayer. Prenylation attaches cys residue at or near c terminus. In these lipid proteins the lipid hydrocarbon chains are embedded in the bilayer, but the protein itself does not enter the bilayer. The anchors used to insert proteins at the cytosolic face are not used for the exoplasmic face and vice versa.
