... HinCel 6A (Tyr104 and Glu108,Table 2. Amino acid residues interacting with the ligands or poten-tially involved in the catalysis, and the corresponding residues of HjeCel 6A, HinCel 6A and HinCel6B. ... 1.14 A ˚(CcCel6C–HjeCel 6A, 1QK0 chain A) and 1.30 A ˚(CcCel6C–HinCel6B, 1DYS chain A) formain chain atoms.The significant feature in cellobiohydrolasesHjeCel 6A and HinCel 6A is their active ... ligand binding produces a conformational change that narrowsthis tunnel. In contrast, the tunnel remains wide in CcCel6C and the con-formational change appears to be less favourable than in...