Crystallographic studies of the coupling segment NBD94_674–781 of the nucleotide-binding domain of the Plasmodium yoelii reticulocyte-binding protein Py235

The Plasmodium yoelii reticulocyte-binding protein Py235 has a role as an ATP/ADP sensor. The sensor domain of Py235 is called NBD94; it consists of at least three functional regions, the nucleotide-binding region (NBD94_444–547), hinge region (NBD94_566–663) and C-terminal coupling region (NBD94_674–781), and has been proposed to link ATP/ADP binding to the interaction of Py235 with the red blood cell. Here, NBD94_674–781 was cloned, expressed and purified to high purity. The monodisperse protein was crystallized by vapour diffusion. A diffraction data set was collected to 2.9 Å resolution with 97.2% completeness using a synchrotron-radiation source. The crystals belonged to space group C2, with unit-cell parameters a = 65.08, b = 82.71, c = 114.27 Å, β = 94.72°, and contained four molecules in the asymmetric unit.