The DNA double helix is a semi-flexible polymer with twist rigidity. Its bending elasticity gives rise to entropic polymer elasticity, which can be precisely studied in single-molecule experiments. DNA's twist rigidity causes it to wrap around itself, or 'supercoil', when it is sufficiently twisted; thermal fluctuations destabilize supercoiling for DNAs twisted fewer than once per twist persistence length. Twisted DNAs under tension, braided DNAs, and the internal dynamics of supercoiled DNAs are discussed. The interplay between braiding and supercoiling free energy is argued to be important for the decatenation of duplicated DNAs in prokaryote cells.
|Original language||English (US)|
|Number of pages||12|
|Journal||Materials Research Society Symposium - Proceedings|
|State||Published - Jan 1 1997|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials