Purification and Characterization of α-Galactosidase from Watermelon
1986 年 99 巻 1 号 p. 243-250
詳細
1986 年 99 巻 1 号 p. 243-250
An α-galactosidase [EC 3.2.1.22] was isolated from the fruit of the watermelon, Citrullus battich. The enzyme was purified by procedures including extraction, ammonium sulfate precipitation, and chromatographies on DEAE-Sephadex, CM-Sephadex and Sephadex G-100. The final preparation was found to be fairly homogeneous on disc and SDS-polyacrylamide gel electrophoresis, and sufficiently free from other glycosidase activities. The molecular weight of the enzyme was estimated to be 45, 000 by Sephadex G-100 column chromatography and SDS-polyacrylamide gel electrophoresis. The enzyme was most active at pH 4.5 for natural substrates and at 5.9 for artificial substrates. The enzyme liberates the α-galactose units from oligosaccharides of the raflinose series and ceramide trihexoside, and the hemagglutination-inhibiting activities of human ovarian cyst B-glyco-protein and blood group B-type ghosts were abolished by the enzyme.
