ABSTRACT
N-glycosides of nitroaniline, D-glucose, D-mannose, D-galactose, D-ribose, D-xylose and L-arabinose were examined as acceptors of glucose in transglycosylation reactions. In the presence of these compounds, higher N-glycosides of nitroaniline were formed in the course of incubation of acid glucoamylase with maltose or glycogen. With the exception of N-glycosides of D-galactose and L-arabinose, the remaining compounds were acceptors of glucose. It follows that the acceptor properties of N-glycosides of nitroaniline are dependent on the spatial position of the hydroxyl group on the fourth carbon of the sugar moiety.
Subject(s)
Aniline Compounds/metabolism , Glucan 1,4-alpha-Glucosidase/metabolism , Glucose/metabolism , Glucosidases/metabolism , Glycosides/metabolism , Animals , Cattle , Myocardium/enzymology , Nitro Compounds/metabolism , Spleen/enzymologyABSTRACT
The present paper supplements the previous investigations on the mechanism of reactions catalyzed by amylolytic enzymes. The performed experiments corroborated the data on transglucosylative properties of animal glucoamylases which were found to depend on the structure and concentration of substrate. The p-nitroanilines were first introduced in this type of research enabling to find the differences of activity mechanism of animal glucoamylases and Aspergillus niger glucoamylase. In complement to the data reported by Japanese students the transglucosylative properties of glucoamylases were shown to depend not only on the enzyme origin and substrate concentration but also on the chemical composition of applied substrate and concentration of hydrogen ions in the reaction medium.