Structure of the H107R variant of the extracellular domain of mouse NKR-P1A at 2.3 A resolution

The structure of the H107R variant of the extracellular domain of the mouse natural killer cell receptor NKR-P1A has been determined by X-ray diffraction at 2.3 angstrom resolution from a merohedrally twinned crystal. Unlike the structure of the wild-type receptor in space group I4122 with a single chain per asymmetric unit, the crystals of the variant belonged to space group I41 with a dimer in the asymmetric unit. Different degrees of merohedral twinning were detected in five data sets collected from different crystals. The mutation does not have a significant impact on the overall structure, but led to the binding of an additional phosphate ion at the interface of the molecules.