Structure of the ternary complex.
(A) three-dimensional structure of the hTopIB-DNA-IQN2 ternary complex. Topoisomerase core subdomains I, II and III are represented in blue, yellow and red, respectively, while the linker and C-terminal domains in green and cyan, respectively. DNA strands are colored in orange (uncleaved strand), purple (cleaved upstream) and dark purple (cleaved downstream). IQN2 is shown in magenta using ball and stick representation. Chemical structures of AI-III-52 (1), NSC 314622 (IQN2) (2) and MJ-238 (3).