fig3

Figure 3. The mechanism of action of hTopIB by controlled rotation. The figure shows the different steps of enzyme catalysis during DNA relaxation, starting from hTopIB binding to enzyme release. The magnification in the controlled rotation step represents the catalytic pentad. The enzyme core domain is in red, the linker is in green, the C-terminal domain is in yellow, and DNA is in blue. This molecular picture was produced with UCSF Chimera program^[35]