The Role of Lipid-Linked Activated Sugars in Glycosylation Reactions

Abstract

In the prokaryotic eubacteria the single cytoplasmic membrane appears to serve many of the functions performed by the numerous subcellular organelles found in eukaryotic organisms. Thus, the cytoplasmic membrane of the bacteria is the site of oxidative phosphorylation; it is the site of active transport; and it is the site of biosynthesis of many of the macromolecular components of the cell surface. In this chapter attention will be focused on biosynthesis of the sugar-containing macromolecules that ultimately reside within or outside the membrane surface. More specifically it will deal with the mechanism of energy utilization in the biosynthetic processes involving glycosyl transfers from high energy, lipid-linked sugar intermediates first found in the eubacteria. It should be noted, however, that although it is in the prokaryotic bacteria where such systems have been most definitely established, preliminary reports suggest that analogous reactions may occur in eukaryotic cells.^1,2,3