The extracellular xylan degradative system in Clostridium cellulolyticum cultivated on xylan: evidence for cell-free cellulosome production.

ABSTRACT: In this study, we demonstrate that the cellulosome of Clostridium cellulolyticum grown on xylan is not associated with the bacterial cell. Indeed, the large majority of the activity (about 90%) is localized in the cell-free fraction when the bacterium is grown on xylan. Furthermore, about 70% of the detected xylanase activity is associated with cell-free high-molecular-weight complexes containing avicelase activity and the cellulosomal scaffolding protein CipC. The same repartition is observed with carboxymethyl cellulase activity. The cellulose adhesion of xylan-grown cells is sharply reduced in comparison with cellulose-grown cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that cellulosomes derived from xylan- and cellulose-grown cells have different co

SUBMITTER: Mohand-Oussaid O 

PROVIDER: S-EPMC93894 | biostudies-literature | 1999 Jul

REPOSITORIES: biostudies-literature