Crystallographic analysis of maltohexaose-producing amylase from alkalophilic Bacillus sp.707

Preparation and crystallization G6-amylase from alkalophilic Bacillus sp.707 was expressed by Bacillus subtilis 207-25. The enzyme was crystallized by the hanging drop vapor diffusion method using the reservoir solution containing 50% (v/v) 2methylpentane-2, 4-diol, 100 mM Tris-HCl (pH 8.5) and 200 mM ammonium phosphate. Calcium chloride and sodium chloride were added to final 1 mM in the drop solution. Rod-like crystals were grown within 4 days at room temperature. Crystals of the complex with pseudomaltononaose were obtained by soaking the crystal for 3 days in the crystallization solution containing 10 mM acarbose and 10 mM maltotriose.