Glycosidases induced in Aspergillus tamarii. Mycelial alpha-D-galactosidases.
Two alpha-D-galactosidases (alpha-D-galactoside galactohydrolase, EC 3.2.1.22) produced by Aspergillus tamarii were purified from the mycelial extract by a procedure including chromatography on hydroxyapatite, DEAE-cellulose and ECTEOLA-cellulose. Each of these enzymes showed a single protein band corresponding to the alpha-D-galactosidase activity when examined by polyacrylamide-gel electrophoresis. They catalysed the hydrolysis of o-nitrophenyl alpha-D-galactoside, melibiose, raffinose and stachyose, but did not attack the galactomannans. Their Mr values were respectively 265000 +/- 5000 and 254000 +/- 5000 by the method of Hedrick & Smith [(1968) Arch. Biochem. Biophys. 126, 155-164]. Polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate in each case showed a single protein band, with Mr 88000 and 77500 respectively. The purified enzymes contained carbohydrate, consisting of N-acetylglucosamine, mannose, glucose and galactose in the estimated molar proportions of 1:9:5:8 in alpha-galactosidase I.
D001230:Aspergillus / Q000201:enzymology*; D002412:Cations / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004790:Enzyme Induction; D005696:Galactosidases / Q000096:biosynthesis*; D006601:Hexoses / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D013379:Substrate Specificity; D000519:alpha-Galactosidase / Q000096:biosynthesis* / Q000302:isolation & purification
D002412:Cations; D006601:Hexoses; D005696:Galactosidases; D000519:alpha-Galactosidase