title: DNA flexibility on short length scales probed by atomic force microscopy.
abstract: Unusually high bending flexibility has been recently reported for DNA on short length scales. We use atomic force microscopy (AFM) in solution to obtain a direct estimate of DNA bending statistics for scales down to one helical turn. It appears that DNA behaves as a Gaussian chain and is well described by the wormlike chain model at length scales beyond 3 helical turns (10.5 nm). Below this threshold, the AFM data exhibit growing noise because of experimental limitations. This noise may hide small deviations from the Gaussian behavior, but they can hardly be significant.
authors.affiliation: UPR9080 CNRS, Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13, rue Pierre et Marie Curie, Paris, 75005, France.
authors.forename: Alexey K
authors.initials: AK
authors.lastname: Mazur
authors.affiliation: Institut Charles Sadron, CNRS-University of Strasbourg, 23 rue du Loess, BP 84087, 67034 Strasbourg cedex 2, France.
authors.forename: Mounir
authors.initials: M
authors.lastname: Maaloum
mesh_terms: D004247:DNA / Q000737:chemistry*; D004548:Elasticity; D018625:Microscopy, Atomic Force / Q000379:methods; D008956:Models, Chemical; D009690:Nucleic Acid Conformation
chemical_list: D004247:DNA