THE CELLULOSE OF THE ANAEROBIC BACTERIUM CLOSTRIDIUM-THERMOCELLUM - ISOLATION, DISSOCIATION, AND REASSOCIATION OF THE CELLULOSOME

The cellulosome of Clostridium thermocellum, isolated from the extracellular cellulase system by affinity chromatography on Whatman CC41 cellulose, contained > 95% of the carboxylmethylcellulase activity applied to the column and could extensively solubilise "crystalline" cellulose when incubated in the presence of Ca2+ and dithiothreitol. An aqueous solution of the cellulosome could be dissociated into polypeptides by 0.5% sodium dodecyl sulphate-10mM ethylenediaminetetra-acetic acid-10mM dithiothreitol at 25-degrees or 30-degrees and pH 5. After dialysis, the polypeptides reassociated and there was a complete recovery of activity towards "crystalline" cellulose.