Abstract
1. The active protein of transglucosidase relating to B2 was isolated in partially purified form from the cell extract of E. coil, and the specificity of this preparation was investigated.
2. It was demonstrated that the enzyme utilized only maltose as a glucosyl donor since it has α-glucosyl linkage, which is indispensable to the transglucosidation reaction.
3. The transglucosidase reacted with several isoalloxazine derivatives and synthesized the corresponding glucosides, isomaltosides and various oligosaccharides. Together with the evidence obtained from the inhibition experiments with B2 analogues, these results confirm the preliminary posturation of B2 that the isoalloxazine group plays an important role to interact with the enzyme molecule.
4. Quinacrine, quinine and other related compounds inhibited the transglucosidation, since they have relative affinity to the protein of transferase so as to reveal competition with B2 in the reaction system.
