Crystallization and preliminary diffraction data analysis of both single and pseudo-merohedrally twinned crystals of rubredoxin oxygen oxidoreductase from Desulfovibrio gigas.

Crystals of rubredoxin oxygen oxidoreductase have been obtained and characterized. They belong to space group P2(1)2(1)2, with unit-cell dimensions a = 88.24 (15), b = 101.25 (7), c = 90.80 (3) A. The homodimer (86 kDa) in the asymmetric unit is related by a non-crystallographic twofold rotation axis parallel to the ab 'diagonal' direction, as shown by the self-rotation maximum in the section with chi = 180 degrees. This pseudo-crystallographic symmetry element was also found to be the twinning axis of pseudo-merohedrally twinned crystals, leading to apparent pseudo-tetragonal P42(1)2 crystal symmetry.