Applications of thermal-gradients method for the optimization of α-amylase crystallization conditions based on dynamic and static light scattering data

Abstract The expression, purification, crystallization, and characterization by X-ray diffraction of α-amylase are described here. Dynamic and static light scattering methods with a temperature controller was used to optimize the crystallization conditions of α-amylase from Bacillus stearothermophilus an important enzyme in many fields of industrial activity. After applying thermal gradients for growing crystals, X-ray cryo-crystallographic methods were employed for the data collection. Crystals grown by these thermal-gradients diffracted up to a maximum resolution of 3.8 A, which allowed the determination of the unit cell constants as follows: a=61.7 A , b=86.7 A , c=92.2 A and space group C 222 (or C 222 1 ).