Cloning, expression, purification and crystallization of dihydroxybutanone phosphate synthase from Magnaporthe grisea.

Dihydroxybutanone phosphate synthase (DS) catalyzes a commitment step in riboflavin biosynthesis where ribulose 5-phosphate is converted to dihydroxybutanone phosphate and formate. DS was cloned from the pathogenic fungus Magnaporthe grisea (using functional complementation of an Escherichia coli DS knockout mutant) and expressed in E. coli. The purified protein crystallized in space group P2(1)2(1)2. Diffraction data extending to 1.5, 1.0 and 1.8 A resolution were collected from crystals that were divalent cation free, soaked in Zn(2+) or soaked in Mg(2+), respectively.