title: Laser-assisted single-molecule refolding (LASR).
abstract: To assemble into functional structures, biopolymers search for global minima through their folding potential energy surfaces to find the native conformation. However, this process can be hindered by the presence of kinetic traps. Here, we present a new single-molecule technique, termed laser-assisted single-molecule refolding (LASR), to characterize kinetic traps at the single-molecule level. LASR combines temperature-jump kinetics and single-molecule spectroscopy. We demonstrate the use of LASR to measure single-molecule DNA melting curves with ∼1°C accuracy and to determine the activation barrier of a model kinetic trap. We also show how LASR, in combination with mutagenesis, can be used to estimate the yields of competing pathways, as well as to generate and characterize transient, unstable complexes.
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, Michigan, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhao
authors.forename: Myles
authors.initials: M
authors.lastname: Marshall
authors.forename: Elvin A
authors.initials: EA
authors.lastname: Alemán
authors.forename: Rajan
authors.initials: R
authors.lastname: Lamichhane
authors.forename: Andrew
authors.initials: A
authors.lastname: Feig
authors.forename: David
authors.initials: D
authors.lastname: Rueda
mesh_terms: D002138:Calibration; D004247:DNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D055029:Inverted Repeat Sequences; D007700:Kinetics; D007834:Lasers; D008954:Models, Biological; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D012313:RNA / Q000235:genetics / Q000378:metabolism; D044366:Transition Temperature
chemical_list: D012313:RNA; D004247:DNA