CRYSTALLIZATION AND PRELIMINARY-X-RAY ANALYSIS OF THE MAJOR CELLULOSE-BINDING DOMAIN OF THE CELLULOSOME FROM CLOSTRIDIUM-THERMOCELLUM

The cellulose-binding domain from the scaffoldin subunit of the cellul osome from Clostridium thermocellum strain YS has been expressed in Es cherichia coli, purified to homogeneity and crystallized. Crystals wer e grown by vapor diffusion using polyethylene glycol as precipitant. T hey belong to the monoclinic space group C2 with unit cell dimensions of a 64.68 Angstrom, b = 50.38 Angstrom C = 96.27 Angstrom; beta = 99. 43 degrees, and density packing considerations suggest that the asymme tric unit contains two molecules. The crystals diffract beyond 2.0 Ang strom resolution using a laboratory rotating anode source.