Crystallization and preliminary X-ray diffraction studies of a novel killer toxin from a halotolerant yeast Pichia farinosa

A killer toxin from a halotolerant yeast, Pichia farinosa strain KK1, was crystallized at high- and low-salt concentrations. Crystals from the high-salt solution belonged to the tetragonal space group P4₁2₁2 or P4₃2₁2, with unit-cell dimensions of a = b = 81.10, c = 118.46 Å. The low-salt solution provided crystals that belonged to the same space group, with nearly same cell dimensions. Preliminary diffraction studies showed that the intensity distributions are significantly different between the two crystals. Both types of crystals contained either two or three molecules per asymmetric unit. They diffracted X-rays beyond 2.0 Å resolution and were stable to X-ray irradiation.