Degradation of cellulases in cultures of Cellulomonas fimi

Endoglucanases CenA, CenB and CenD, cellobiohydrolases CbhA and CbhB, and the mixed function xylanase-exoglucanase Cex are degraded proteolytically in the supernatants of cultures of Cellulomonas fimi growing with cellulose. All of these polypeptides are modular. The initial sites of proteolysis are within or adjacent to the linkers connecting the modules, leading to the appearance of discrete fragments of the enzymes which retain the functions of the component modules.