FIGURE 2.

β-Glucosidase and endo-glucanase activities of the wild type strain and β-glucosidase deletion mutants. (A) β-Glucosidase activities of cells cultured in glucose. (B) β-Glucosidase activities of cells cultured in cellulose. (C) Endo-glucanase activities of cells cultured in glucose. (D) Endo-glucanase activities of cells cultured in cellulose. β-Glucosidase activity was determined using pNPG as the substrate, and endo-glucanase activity was determined using CMC-Na as the substrate. Values are the mean of three biological replicates. Error bars are the standard deviations from these replicates. Error bars indicate standard errors. Because the ΔbglA/bglB mutant could not grow in cellulose 0.05% glucose was added into the medium to ensure the growth of ΔbglA/bglB (B,D), the wild type strain and other single deletion mutants were grown with cellulose as sole carbon source.