beta-Maltose → Trehalose

Reaction equation

[CH2:1]([OH:23])[C@H:2]1[O:7][C@H:6]([O:8][C@H:9]2[C@H:14]([OH:15])[C@@H:13]([OH:16])[C@H:12]([OH:17])O[C@@H]2CO)[C@H:5]([OH:20])[C@@H:4]([OH:21])[C@@H:3]1[OH:22].N([CH2:28][CH2:29][OH:30])CCO.ClC(Cl)(Cl)C(O)=[O:34]>>[CH2:29]([OH:30])[C@H:28]1[O:34][C@H:9]([O:8][C@H:6]2[O:7][C@H:2]([CH2:1][OH:23])[C@@H:3]([OH:22])[C@H:4]([OH:21])[C@H:5]2[OH:20])[C@H:14]([OH:15])[C@@H:13]([OH:16])[C@@H:12]1[OH:17]

Participants

Reactant 3

HCID 6255beta-Maltose

HCID 6421Trichloroacetic Acid

HCID 8113Diethanolamine

Product 1

HCID 7427Trehalose

Procedure

Transformed E. coli ATCC35467/pCJ121, ATCC35467/pCJ122 and ATCC35467/pCJ123 were cultured on an LB-Ap medium until the early resting stage. The cells were recovered by centrifuigation and washed twice with an appropriate volume of 20 mM diethanolamine solution. The washed cells were suspended in an appropriate volume of 20 mM diethanolamine solution and crushed by ultrasonicater. The crushed cells were centrifuged and the supematant obtained therefrom was used as enzymatic liquid. The supematant was reacted with 20% maltose solution containing 20 mM diethanolamine, pH 8.5 to 9.0 at 35° C. 1.0% trichloroacetic acid was added to the reaction solution, and centrifugation and HPLC were conducted for analysis. One unit of enzyme activity was defined as a quantity of enzyme when it produced 1 μl of trehalose per minute. The results are shown in Table 5 below.