Fig. 2

Crystal structure of d-arabinose dehydrogenase from S. solfataricus (PDB: 2H6E). a Overall fold is represented by a ribbon diagram. The catalytic domain is shown in green, where the N-terminal and C-terminal segments of the catalytic domain are shown in light and dark green, respectively. The nucleotide binding domain is shown in yellow. Zn²⁺ ion is shown as a purple sphere. The dashed line represents a missing part of the crystal structure due to weak electron density (here reconstructed by homology modelling). b Tetrameric quaternary structure generated by crystallographic symmetry operations. c Coordination geometry of the catalytic Zn²⁺ ion. d Coordination geometry of the structural Zn.²⁺ ion. (All structural figures in this article were prepared using Pymol [40] software)