Crystallization and preliminary X-ray analysis of the Saccharomycopsis fibuligera glucoamylase expressed from the GLU1 gene in Escherichia coli

The active non-glycosylated glucoamylase, overexpressed from the Saccharomycopsis fibuligera GLU1 gene in Escherichia coli BL21(DE3), has been purified from the solubilized inclusion bodies and then renatured in vitro. Crystals of the recombinant glucoamylase were obtained by vapour diffusion using PEG as precipitant. The crystals belong to the orthorhombic space group P2₁2₁2₁, with unit-cell dimensions of a = 58.1, b = 87.8 and c = 99.9 Å, and diffract to 1.7 Å resolution. This is the first report of the crystallization of the full-length glucoamylase corresponding to the mature enzyme.