Reaction Mechanism of a New Glycosyltrehalose-hydrolyzing Enzyme Isolated from the Hyperthermophilic Archaeum, Sulfolobus solfataricus KM1

Biosci Biotechnol Biochem. 1996 Jan;60(5):925-8. doi: 10.1271/bbb.60.925.


Amylolytic activity, which converts soluble starch to α,α-trehalose (trehalose), was found in the cell homogenate of the hyperthermophilic acidophilic archaeum, Sulfolobus solfataricus KM1. Two enzymes, a glycosyltransferase and an α-amylase, which were essential for this activity were identified. The α-amylase was purified to homogeneity on SDS-PAGE. The α-amylase catalyzed the hydrolysis of glycosyltrehaloses to trehalose. Analysis of the reaction products, kinetic parameters, and experimental findings using (3)H-labeIed substrates indicated that the α-amylase hydrolyzed only the α-1,4 glucosidic linkage adjacent to the trehalose unit of the glycosyltrehaloses. Six strains of the Sulfolobaceae family examined were observed to have the glycosyltrehalose-hydrolyzing enzyme, the α-amylase.

Keywords: Sulfolobus solfataricus; glycosyltrehalose; trehalose; α-amylase.