Post-Translational Modifications of Proteins discusses several important topics of interest to researchers and students in protein chemistry and biochemistry, including the occurrence and function of hydroxylated residues and the three enzymes required for their formation; the damaging effects of reactions between sugars and proteins; ADP-riboosylation of proteins outside the nucleus; and Monod, Wyman, and Changeux's concerted model for allosteric control of enzyme activity exemplified by studies on glycogen phosphorylase. The application of Fast Atom Bombardment Mass Spectometry (FAB-MS) to studies on the structure and biosynthesis of various oligosaccharide moieties in protein is examined, and the understanding of the structural diversity and function of glycoprotein oligosaccharides is discussed in this volume.