Preparation of Conjugates of Proteins with Amyloses by Elongation of Covalently Attached Primers Using Glycogen Phosphorylase a1

This paper describes convenient preparations of protein-amylose conjugates. These preparations are based on the elongation of maltooligosaccharides by reaction with glucose-1-phosphate, catalyzed by glycogen phosphorylase a. Coupling of maltooligosaccharides to proteins by reductive amination generated covalently attached primers for the glycogen phosphorylase a-catalyzed polymerization of glucose-1-phosphate. SDS-polyacrylamide gel electrophoresis was useful for characterizing these conjugates. 31P NMR spectroscopy could be used conveniently to assay simultaneously the formation and the enzymatic activity of the amylose-conjugated proteins. This assay could be used directly in reactions catalyzed by glycogen phosphorylase a; it should also he applicable to protein mixtures of greater complexity than the ones used here. Methods of synthesizing enzymatically active neoglycoproteins having a range of molecular weights are described.