FIG. 4.

(A) Time course of the AgdB reaction with maltose as a substrate. The enzyme (0.6 μg) was incubated with 0.5% maltose in 100 μl of 40 mM acetate buffer (pH 5.5) at 45°C. Aliquots were withdrawn at the indicated times and analyzed by TLC. (B) TLC analysis of the transglycosylation products from various α-glucobioses. The purified AgdB (0.6 μg) was incubated with 0.5% (wt/vol) maltose (M), isomaltose (I), nigerose (N), and kojibiose (K) as substrates (Subs.) in 100 μl of 40 mM acetate buffer (pH 5.5) for 2 h at 45°C ([+] or without [−] enzyme [Enz.]), and the reaction products were analyzed by TLC. Glucose (G), maltose (M), isomaltose (I), panose (P), and isomaltotriose (IG3) were used as standards (Std).