Crystallization and preliminary X-ray analysis of endoglucanase from Pyrococcus horikoshii

Structural information on hyperthermostable cellulases is required for bio­process applications in the transformation of biomass. Crystals were obtained of a C-­terminally five-amino-acid truncated hyperthermostable endoglucanase (family 5) from the archaeon Pyrococcus horikoshii. The truncated form of this enzyme showed similar enzymatic properties to the wild-type protein. The enzyme was crystallized by the sitting-drop vapour-diffusion method using ethanol as precipitant at 296 K. An X-ray diffraction data set was collected to 1.78 Å resolution at 100 K. The crystals belonged to space group P4₁2₁2 or P4₃2₁2.