Inhibition of GH6 CBHs by cellobiose. (A) 14C-BC (0.25 mg ml-1) was incubated with a mixture of 0.25 μM TrCel6A and 0.025 μM EG (TrCel5A) at 25°C. (B and C) 14C-BMCC (0.25 mg ml-1) was incubated with 0.25 μM TrCel6A (panel B) or with 0.25 μM CtCel6A (panel C) at 50°C. The concentration of added cellobiose was 0 mM + 0.06 μM N188BG (◊), 1.0 mM (*), 5.0 mM (+), 10 mM (□), 20 mM (Δ), 50 mM (×), or 100 mM (○). (D) Hydrolysis data (from panels A-C) in the coordinates (DCB/DCB=0) versus [cellobiose], where DCB and DCB=0 represent the degree of conversion of 14C-cellulose in the presence and absence of cellobiose, respectively. The average (DCB/DCB=0) values over hydrolysis time points are plotted. Solid lines are from the non-linear regression according to Equation 5. TrCel6A + TrCel5A on 14C-BC (□), TrCel6A on 14C-BMCC (◊), and CtCel6A on 14C-BMCC (×).