Transfer of oligosaccharide from oligosaccharide pyrophosphoryl dolichol to endogenous acceptor proteins in human breast malignant and normal tissues

Summary We have prepared dolichylpyrophosphoryl-[¹⁴C]-oligosaccharide (Dol-PP-oligosaccharide) from calf thyroid. Microsomal fractions from human breast tissues catalyzed the transfer of labeled oligosaccharide to endogenous acceptor proteins. Malignant tumors showed higher activity of the oligosaccharide transferring enzyme than normal tissue. With kojibiose (Kj), and inhibitor of (Glc₃)-glucosidase, an increase in the radioactivity associated with glycoprotein was observed.