C-1-C-X REVISITED - INTRAMOLECULAR SYNERGISM IN A CELLULASE

Endoglucanase A (CenA) from the bacterium Cellulomonas fimi is compose d of a catalytic domain and a nonhydrolytic cellulose-binding domain t hat can function independently. The individual domains interact synerg istically in the disruption and hydrolysis of cellulose fibers. This i ntramolecular synergism is distinct from the well known intermolecular synergism between individual cellulases. The catalytic domain corresp onds to the hydrolytic C-X system and the cellulose-binding domain cor responds to the nonhydrolytic C-1 system postulated by Reese et al. [R eese, E. T., Sui, R. G. H. and Levinson, H. S. (1950) J. Bacteriol. 59 , 485-497] to be required for the hydrolysis of cellulose.