Crystallization and preliminary X-ray diffraction studies of nucleoside diphosphate kinase from Thermus thermophilus HB8.

Nucleoside diphosphate (NDP) kinase contributes to the maintenance of cellular pools of all nucleoside triphosphates (NTPs) by catalyzing the transfer of the gamma-phosphoryl group from an NTP donor to an NDP acceptor. NDP kinase from the extreme thermophilic bacterium Thermus thermophilus HB8 was overexpressed in Escherichia coli and crystallized at 297 K using polyethylene glycol 8000 as the precipitant by means of the hanging-drop vapour-diffusion procedure. The crystals belong to the hexagonal system, space group P6(3)22, with unit-cell parameters a = b = 124.0, c = 104.9 A, alpha = beta = 90, gamma = 120 degrees. Assuming the asymmetric unit to contain two subunits, the calculated V(M) value was 3.7 A(3) Da(-1). The crystals diffracted X-rays generated by the synchrotron at SPring-8 to at least 1.9 A resolution and were suitable for high-resolution X-ray crystal structure determination.