Glycosylation Pattern and Disulfide Assignments of Recombinant Human Differentiation-Stimulating Factor

This report describes the post-translational modifications of recombinant human differentiation-stimulating factor, a 180-residue glycoprotein that is secreted from transfected Chinese hamster ovary cells. Peptic peptides containing six potential N-glycosylation sites were analyzed to determine that Asn residues 9, 34, 63, 73, 96, and 116 were utilized. Additional peptides, generated by tryptic digestion of peptic fragments, allowed the assignments of three intrachain disulfide bonds (Cys-18 to Cys-131, Cys-12 to Cys-134, and Cys-60 to Cys-163).