Purification, crystallization and preliminary crystallographic analysis of RecA superfamily ATPase PH0284 from Pyrococcus horikoshii OT3

Abstract

Circadian (daily) protein clocks are found in cyanobacteria, where a complex of the KaiA, KaiB and KaiC proteins generates circadian rhythms. The 28.09 kDa KaiC homologue PH0284 protein from Pyrococcus horikoshii OT3 was cloned and expressed and the purified protein was crystallized by the oil-microbatch method at 295 K. X-ray diffraction data from the crystal were collected to 2.0 Å resolution using synchrotron radiation at 100 K. The crystal belongs to the trigonal space group P3221, with unit-cell parameters a = b = 96.06, c = 298.90 Å. Assuming the presence of one hexamer in the asymmetric unit gives a VM value of 2.36 Å3 Da-1 and a solvent content of 47.9%. A cocrystal with ATP was prepared and a diffraction data set was collected at 2.3 Å resolution. © 2006 International Union of Crystallography. All rights reserved.