Carbohydrate structure of hamster plasma fibronectin. Evidence for chemical diversity between cellular and plasma fibronectins.

The structure of the carbohydrate moiety of hamster plasma fibronectin was determined. The glycopeptides and oligosaccharides released by hydrazinolysis (Fukuda, M., Kondo, T., and Osawa, T. (1976) J. Biochem. (Tokyo) 80, 1223-1232) were analyzed by methylation and exoglycosidase digestion and the major oligosaccharide unit of hamster plasma fibronectin was shown to be (formula, see text) The structure of carbohydrate moiety of plasma fibronectin shown above (NeuGly, N-glycolyl-neuraminic acid) and that of cellular fibronectin (Fukuda, M., and Hakomori, S. (1979) J. Biol. Chem. 254, 5451-5457) are distinctly different with respect to the linkage of sialic acid, the degree of sialylation and the absence or presence of fucose. These results, therefore, provide the evidence for chemical diversity between cellular (fibroblast) and plasma fibronectins.