Fig. 3

The structural and functional analysis of each subunit. a The superimposition of the Cα traces of the ScADAT2 and SaTadA structures (PDB 2B3J, magenta), and the color scheme of ScADAT2 (PDB 7BV5) is as in Fig. 1: catalytic domain in cyan and C-tail in red. b The close-up of the zinc-binding site of ScADAT2. The distances are indicated, and the purple and red spheres represent the zinc ion and the catalytic water molecule (W), respectively. c The C35-G36 recognition by SaTadA (magenta). The hydrogen bonds are indicated by the red dashed lines. The superimposed ScADAT2 structure is colored cyan. d Structural resemblance of a representative of the RRM (left, PDB 3HI9) to that of the RLD (the contents in the box on the right, PDB 7BV5) domains. RLD is shown in both ribbon and surface charge rendering in the same orientation, which are related by a 90° rotation. The 70HLKR73 region is shown in sticks in the cartoon representation (right). e The EMSA assay on the binding affinities of the WT and mutant enzymes concerning the tRNA-binding residues in ScADAT3. The molar ratios of the enzyme to tRNA are shown above the gel while bands for the free and enzyme-bound tRNA are indicated on the left