Crystallization and preliminary X-ray diffraction analysis of the secreted protein Athe-0614 from Caldicellulosiruptor bescii

The Athe-0614 protein is a component of the extracellular proteins secreted by the anaerobic, extremely thermophilic and cellulolytic bacterium Caldicellulosiruptor bescii. The recombinant protein was expressed in Escherichia coli, purified to near-homogeneity and crystallized using polyethylene glycol 2000 monomethyl ether as a precipitant. The crystals belonged to the monoclinic space group P21, with unit-cell parameters a = 48.4, b = 42.2, c = 97.8 Å, β = 96.1°, and diffracted to 2.7 Å resolution using synchrotron radiation.