Identification of the Clostridial cellulose synthase and characterization of the cognate glycosyl hydrolase, CcsZ
Fig 9
Endocellulase activity was assessed using a bimodified cellopentaose substrate that contains terminal p-nitrophenyl and 3-ketobutylidene groups. CcsZ and the positive control (a cellulase cocktail from Trichoderma reesei) demonstrated endocellulase activity in the coupled enzyme assay with an ancillary exo-β-glucosidase. CcsZ did not demonstrate exo-activity, since degradation of the endo-released products and concomitant release of p-nitrophenolate was not observed in the absence of the supplied exo-β-glucosidase. Data are the results of at least 4 replicates. ns = not significant (ANOVA, F (3, 12) = 3770, q = 1.920, p = 0.1834).