Cellulase S (CelS) is synonymous with the major cellobiohydrolase (subunit S8) from the cellulosome of Clostridium thermocellum.

The controversy regarding the identity of a major cellulosomal component type from two different strains of Clostridium thermocellum has been resolved. The principal cellobiohydrolase, subunit S8, from the cellulosome of strain YS has been demonstrated to be synonymous with cellulase component S (CelS) from the cellulosome of ATCC strain 27405. This component is not related to any other cellulosomal subunit or cloned endoglucanase in this organism. [ABSTRACT FROM AUTHOR]