Figure 7.

Inhibition of the catalytic activity of purified yeast DNA topoisomerase II by m-AMSA, Capridine β, and IE1 as measured by relaxation. Supercoiled pBR322 plasmid DNA (lane 1) was relaxed by purified yeast topoisomerase II in the absence (lane 2) or presence of m-AMSA at 10, 50, 100 or 200 μM or with analyzed compounds at 1, 5, 10, 50, 100, 150 or 200 μM. The resulting topological forms of DNA were separated by gel electrophoreses. SC: Supercoiled DNA; R: Relaxed DNA; T: DNA topoisomers. Data shown are typical of three independent experiments.