Continuation is proposed of a program for study of the hydrolases of mammalian acid mucopolysaccharide catabolism. Currently interest centers on the mode of catabolism of O,N-disulfo-gamma-glucosaminyl linkages in heparan sulfate. The problem is being approached by use as test substrates of oligosaccharides derived from heparin. The structures of such oligosaccharides is an object for study as well. Other present work is concerned with the development of sensitive fluorometric assays for gamma-L-iduronidase and gamma-acetylglucosaminidase. BIBLIOGRAPHIC REFERENCES: Weissmann, D.C. Cashman, and R. Santiago, Conn. Tiss. Res. 3 7 (1975). Concerted action of beta-glucoronidase and beta-acetylglucosaminidase on hyaluronodextrins.