title: Trehalose facilitates DNA melting: a single-molecule optical tweezers study.
abstract: Using optical tweezers, here we show that the overstretching transition force of double-stranded DNA (dsDNA) is lowered significantly by the addition of the disaccharide trehalose as well as certain polyol osmolytes. This effect is found to depend linearly on the logarithm of the trehalose concentration. We propose an entropic driving mechanism for the experimentally observed destabilization of dsDNA that is rooted in the higher affinity of the DNA bases for trehalose than for water, which promotes base exposure and DNA melting. Molecular dynamics simulation reveals the direct interaction of trehalose with nucleobases. Experiments with other osmolytes confirm that the extent of dsDNA destabilization is governed by the ratio between polar and apolar fractions of an osmolyte.
authors.affiliation: AMOLF Institute, Science Park 104, 1098 XG Amsterdam, The Netherlands. mashaghi@amolf.nl.
authors.forename: Sergey
authors.initials: S
authors.lastname: Bezrukavnikov
authors.forename: Alireza
authors.initials: A
authors.lastname: Mashaghi
authors.forename: Roeland J
authors.initials: RJ
authors.lastname: van Wijk
authors.forename: Chan
authors.initials: C
authors.lastname: Gu
authors.forename: Li Jiang
authors.initials: LJ
authors.lastname: Yang
authors.forename: Yi Qin
authors.initials: YQ
authors.lastname: Gao
authors.forename: Sander J
authors.initials: SJ
authors.lastname: Tans
mesh_terms: D003596:Cytosine / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D006147:Guanine / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D018625:Microscopy, Atomic Force; D056004:Molecular Dynamics Simulation; D009690:Nucleic Acid Conformation; D052898:Optical Tweezers; D011108:Polymers / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics; D014199:Trehalose / Q000737:chemistry*
chemical_list: D004277:DNA, Single-Stranded; D011108:Polymers; D011137:Polystyrenes; C024617:polyol; D006147:Guanine; D003596:Cytosine; D004247:DNA; D014199:Trehalose