Crystallization and preliminary X-ray diffraction study of L-lactate oxidase (LOX), R181M mutant, from Aerococcus viridans.

L-Lactate oxidase (LOX) from Aerococcus viridans is a member of the alpha-hydroxyacid oxidase flavoenzyme family. An X-ray crystallographic study of a LOX mutant in which Arg181 is replaced by Met was initiated in order to understand the functions of the conserved amino-acid residues around the FMN in the enzyme active site. LOX-R181M crystals belong to the tetragonal space group I422, with unit-cell parameters a = b = 192.632, c = 200.263 A, alpha = beta = gamma = 90 degrees. There are four monomers in the asymmetric unit. Diffraction data were collected under cryogenic conditions to 2.44 A resolution from LOX-R181M crystals at BL41XU, SPring-8.