Functional Expression of a DNA-Topoisomerase IB from Cryptosporidium parvum
Figure 3
Effects of CPT, topotecan, and SN-38 on the stabilization of covalent TopIB-DNA cleavable complexes. Standard cleavage assay (Material and Methods) were carried out with final concentrations of CPT, topotecan, and SN-38 of 10 and 100 M. CPT was added at a final concentration of DMSO of 1%. The reactions were incubated at 30 for 30 minutes and then stopped with a mixture of 1% SDS and 6.1 g of proteinase K. The reaction products were resolved in a 1% agarose gel and visualized by ethidium bromide staining. Sc: supercoiled DNA, R: relaxed DNA, N: nicked DNA.