Fig. 4: Orthogonal views in surface representation of the 2.0 Å X-ray crystal structure of the delafloxacin-core cleavage complex of S.pneumoniae topo IV with 18-mer V gate DNA (PDB ID: 8QMB).
From: Structural basis of topoisomerase targeting by delafloxacin

The ParE TOPRIM domains are in yellow, ParC domains in blue, DNA is in red (cartoon representation) and the two drug molecules are in pink (solid sphere representation). The two surface potassium ions bound one to each ParC tower are in dark purple (solid sphere representation) highlighted by dark circles (top) and arrows (bottom left).