The hydrolysis of glycosyl fluorides by glycosidases

Abstract

1. α-d- and β-d-Glucopyranosyl, α-d- and β-d-galactopyranosyl, α-d-mannopyranosyl and α-d-xylopyranosyl fluorides were hydrolysed specifically by the respective glycosidases from several sources. 2. Use of specific inhibitors with a mixture of glycosidases from Helix pomatia intestinal juice showed that each glycosyl fluoride was hydrolysed only by the respective glycosidase. α-d-Glucopyranosidase and α-d-xylopyranosidase activities were shown to be due to different enzymes. 3. Partially purified enzyme preparations containing only one of the glycosidase activities hydrolysed only the corresponding glycosyl fluoride. 4. The configuration at C-1 of α-d-mannopyranosyl fluoride was confirmed since it was hydrolysed by an α-d-mannosidase preparation that contained no detectable β-d-mannosidase activity. 5. An attempt to prepare o-nitrophenyl β-d-mannopyranoside led only to o-nitrophenyl α-d-mannopyranoside.