Crystallization and preliminary X‐ray analysis of PH1566, a putative ribosomal RNA‐processing factor from the hyperthermophilic archaeon Pyrococcus horikoshii OT3

A putative ribosomal RNA‐processing factor consisting of two KH domains from Pyrococcus horikoshii OT3 (PH1566; 25 kDa) was crystallized by the sitting‐drop vapour‐diffusion method using PEG 3000 as the precipitant. The crystals diffracted X‐rays to beyond 2.0 Å resolution using a synchrotron‐radiation source. The space group of the crystals was determined as primitive orthorhombic P 2 1 2 1 2 1 , with unit‐cell parameters a = 45.9, b = 47.4, c = 95.7 Å. The crystals contain one molecule in the asymmetric unit ( V M = 2.5 Å 3  Da −1 ) and have a solvent content of 50%.