Fig. 2

The phylogenetic tree and overall structures of GH11 and GH10 xylanases. a Phylogenetic tree resulting from the analysis of amino acid sequences of A. niger xylanases and other structurally characterized xylanases from Eukaryota constructed using the neighbor-joining method. Numbers on nodes correspond to the percentage bootstrap values for 1000 replicates. b The β-jelly roll structures of XynA, XynB, XynD and XynE from the GH11 family. c The (β/α)₈-barrel structure of XynC from the GH10 family. The substrate sugar ring is represented by a sphere and green sticks. Catalytic amino acids Glu are shown as red sticks