Comparison of sulfation of glycosaminoglycans and glycopeptides from control and virus-transformed baby hamster kidney cells.

ABSTRACT

Sulfation of glycosaminoglycans and glycopeptides was compared in baby hamster kidney (BHK) cells and the polyoma virus transformants (PY-BHK). Cells were incubated with [3H]glucosamine and [35S]sulfate, and the labeled glycosaminoglycans and glycopeptides were isolated by digesting the cell membrane fraction with pronase followed by gel filtration. Each type of glycosaminoglycan in the void volume fraction (Fraction I) and in the included fraction (Fraction II) was determined by sequential enzymatic digestions. The residue was regarded as being glycopeptides. Of the total 3H radioactivities of glycosaminoglycans in Fraction I from BHK cells, 51% were in dermatan sulfate, 23% were in heparan sulfate, 17% were in chondroitin 4- and 6-sulfates, and 9% were in hyaluronate. PY-BHK cells acquired significantly larger amounts of 3H radioactivities in sulfated glycosaminoglycans than did BHK cells on the basis of cell number. On the basis of protein content, there was no such difference due to higher protein content of PY-BHK cells. The degree of sulfation of the glycosaminoglycans, estimated from the ratio of 35S to 3H and by disaccharide analysis, was significantly lower in PY-BHK cells than in BHK cells. Considerable amounts of 35S radioactivities assigned to sulfated glycopeptides were found in Fraction II from both BHK and PY-BHK cells.