1988 Volume 36 Issue 10 Pages 4000-4007
The substrate specificities of the squid liver α-N-acetylgalactosaminidases I and II were studied with natural compounds containing α-N-acetylgalactosaminyl or other glycosyl terminals as substrates. Both α-N-acetylgalactosaminidases I and II hydrolyzed terminal α-N-acetyl-galactosaminyl linkages of the natural compounds investigated; asialo bovine submaxillary mucin, Forssman glycolipid, human ovarian cyst A-glycoprotein and blood group A-type ghosts. On the other hand, the oligosaccharides containing α-galactosyl terminals, ceramide trihexoside and human ovarian cyst B-glycoprotein, were hydrolyzed by α-N-acetylgalactosaminidase I but not by α-N-acetylgalactosaminidase II. The milk oligosaccharides with other glycosyl terminals were nxot hydrolyzed by either enzyme. Application of α-N-acetylgalactosaminidase from squid liver together with other glycosidases was effective in structural studies of Forssman glycolipid.
