Glycosphinoglipid beta-galactosidases of cultured mammalian cells. Characterization of the enzymes from mouse cell line lmtk and human Lesch-Nyhan fibroblasts.

Evidence is presented for the existence of three distinct mammalian glycosphingolipid beta-galactosidase responsible for the hydrolysis of galactosylceramide, lactosylceramide and GM1 gangliside, respectively. Activity toward the (L-3-H)galactose-labeled substrates differed with respect to pH optimum, thermostability, effect of NaCl and inhibition by glycosides and related glycosphinglpids. Comparison of these enzymic acitivites in cultured mouse cell line LMTK- and human beta-galactosiddases could probably be detected in future experiments with somatic cell hybrids (formed by the fusion of these two cell strains by specifically inhibiting activity of mouse origin.