As recently reported in the ALSNews:
“The veil has finally been lifted on an enzyme that is critical to the process of DNA transcription and replication and is a prime target of antibacterial and anticancer drugs. Researchers at Berkeley Lab and the University of California, Berkeley, have produced the first three-dimensional structural images of a DNA-bound type II topoisomerase (topo II) that is responsible for untangling coiled strands of the chromosome during cell division. Preventing topo II from disentangling a cell’s DNA is fatal to the cell, which is why drugs that target topo II serve as agents against bacterial infections and some forms of cancer. This first ever structural image of topo II should help in the development of future antibacterial and anticancer drugs that are even more effective and carry fewer potential side effects.”
The original publication in Nature can be found here: K.C. Dong and J.M. Berger, “Structural basis for Gate-DNA recognition and bending by type IIA topoisomerases,” Nature 250, 1201 (2007).