DNA supercoiling is a feature of almost all DNA molecules. It is a powerful thermodynamic force that drives and directs many DNA associated processes in vivo. The level of supercoiling or DNA spatial conformation is constantly changing due to the activities of proteins and the environmental conditions of the cell. Local and temporal changes in DNA supercoiling affect many cellular processes such as replication, transcription recombination and chromosome organization. DNA biomolecular motors such as DNA topoisomerases and DNA translocases are responsible for maintaining the steady state of supercoiling essential for cell viability. In prokaryotes, DNA supercoiling is expected to play an important role in site-specific recombination, a fundamental process to achieve resolution of dimeric chromosomes, allowing plasmids and chromosome segregation and consequently cell division. During this process, DNA undergoes multiple conformational changes due to the activity of Tyrosine recombinases and a DNA translocase known as FtsK.
Biophysical Journal Volume 96, Issue 3, Supplement 1, February 2009, Page 345a ISSN 0006-3495 DOI: 10.1016/j.bpj.2008.12.1734.