Figure 5.The molecular docking with xylohexaose and cellohexaose and activity analysis of the XynA. (A-B) The docking of XynA with xylohexaose and cellohexaose displayed in a cartoon mode, respectively, and the hydrogen bonds between the XynA with xylohexaose or cellohexaose are partially enlarged. The red dotted line indicates hydrogen bonding interaction. The criterion for hydrogen bond judgment is that the distance between the acceptor and donor atoms should be less than 3 Å. (C-E) Relative activities of the XynA mutants in the hydrolysis of BWX, WAX and barley β-glucan respectively. Each experiment was repeated three times. WT enzyme activity was set to 100%. WT group was used as a control for a significant analysis, * means P <0.05, ** means P <0.01, *** means P <0.0002, and **** means P <0.0001. (F) The spatial position and conservation of residues in space fill model of XynA that may interact with the substrate. The green to purple gradient indicates the degree of conservation. The annotated residues are the mutation sites found by molecular docking.