Purification, crystallization and preliminary X-ray analysis of glutathione peroxidase Gpx3 from Saccharomyces cerevisiae.

The glutathione peroxidase Gpx3 from the yeast Saccharomyces cerevisiae has been overexpressed, purified and crystallized. Both gel-filtration and dynamic light-scattering (DLS) results indicate that Gpx3 is a monomer in solution at a concentration of about 2 mg ml(-1), whereas glutathione peroxidases are normally tetrameric or dimeric. X-ray diffraction data from a single crystal of Gpx3 have been collected to 2.6 A resolution. The crystals are triclinic and belong to space group P1, with unit-cell parameters a = 38.187, b = 43.372, c = 56.870 A, alpha = 71.405, beta = 73.376, gamma = 89.633 degrees. There are two Gpx3 monomers in a crystallographic asymmetric unit. Preliminary analyses show that the yeast Gpx3 is quite different from those of mammals.