Biosynthesis of glycosyl phosphatidylinositol membrane anchors.

Abstract

One kind of lipid anchor, is a glycosyl phosphatidylinositol (GPI). The anchor of the Trypanosoma brucei variant surface glycoprotein exemplifies the GPI solution to membrane attachment. Its structure consists of phosphatidylinositol linked glycosidically to a linear tetrasaccharide composed of one glucosaminyl and three mannosyl residues. The terminal mannose, at the nonreducing end of the glycan, is linked to phosphoethanolamine, and the ethanolamine is in amide linkage to the α-carboxyl group of the protein's C-terminal amino acid residue