This product includes 600 ul of 10 x assay buffer, 500 ul of 10 x concatenated DNA, 110 ul of 10 mM ATP, 600 ul of 0.4 M EDTA, 260 ul of 20 x fluorescence dye, 2 ml of 10 x rinse buffer, one V-bottom plate, a TDD filter plate and one black 96-well plates for 96 assays of DNA decatenation reactions. The assay buffer is optimized for bacterial topoisomerase IV. DNA decatenation enzyme is not included. This kit can be used for DNA decatenation assays of any bacterial topoisomerase IV (the parC-parE complex) enzymes or gyrases.