Crystallization and preliminary X-ray diffraction studies of the eukaryotic iron superoxide dismutase (FeSOD) from Vigna unguiculata

Eukaryotic iron superoxide dismutases (FeSODs) are homodimeric proteins that constitute a fundamental protection against free radicals, which can damage essential cellular mechanisms. The protein was cloned and overexpressed in Escherichia coli with an N-terminal His tag. Crystallization experiments of the protein resulted, after several refined screenings, in crystals suitable for X-ray diffraction analysis. The crystals belong to the monoclinic space group C2, with unit-cell parameters a=82.54, b=48.41, c=64.28 Angstrom, alpha=gamma=90, beta=119.66degrees, and contain one molecule per asymmetric unit. At cryogenic temperatures, the crystals diffracted to a resolution limit of 1.80 Angstrom using synchrotron radiation at the European Synchrotron Radiation Facility (ESRF).