Crystallization and preliminary X-ray diffraction analysis of glutathione-dependent dehydroascorbate reductase from spinach chloroplasts

Glutathione-dependent dehydroascorbate reductase (GSH-DHAR) catalyzes the r eduction of dehydroascorbate to ascorbate using reduced glutathione as the electron donor. GSH-DHAR from spinach chloroplasts produced in Escherichia coli was crystallized by the hanging-drop vapour-diffusion method. The crys tals were monoclinic, space group C2, with unit-cell parameters a = 98.25, b = 39.96, c = 106.86 Angstrom, beta = 110.46 degrees. The asymmetric unit contained two molecules, giving a crystal volume per enzyme mass (VM) of 2. 06 Angstrom (3) Da(-1) and a solvent content of 40.3%. A full set of X-ray diffraction data were collected to 2.2 Angstrom Bragg spacing from three na tive crystals with an overall R-merge of 6.5% and a completeness of 93.4%.