Fig. 4From: Improving the specific activity and pH stability of xylanase XynHBN188A by directed evolutionInteractions of the catalytic residues (E94 and E183, marked in red) and the mutated amino acids (marked in blue) with their surroundings (marked in gray) of XynHBN188A (a) and XynHBN188A217 (b). The green dashed lines indicate hydrogen bonds, the yellow dashed lines indicate electrostatic interactions, and the purple dashed lines indicate salt bridgesBack to article page