Stereoview of a Polder omit map of the zfHDAC6/(S)-6h complex (PDB 6V79; contoured at 2.5 σ). The Zn2+-bound water molecule is contoured at 3.5 σ. Atoms are color-coded as follows: C = light blue (zfHDAC6 monomer A), light gray (zfHDAC6 monomer B), or wheat (inhibitor), N = blue, O = red, Zn2+ = gray sphere, and Zn2+-bound water molecule = small red sphere. Metal coordination and hydrogen bond interactions are indicated by solid and dashed black lines, respectively.