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Updated: Aug 31, 2026

Direct Observation of Enzymes Replicating DNA Using a Single-molecule DNA Stretching Assay
Published on: March 23, 2010
Cleavage of stretched DNA on glass by histones observed with fluorescence microscopy
Yoshihiro Takeda1, Fumitaka Mafuné, Tamotsu Kondow
1Genesis Research Institute, Inc., 717-86 Futamata, Ichikawa, Chiba 272-0001, Japan.
Abstract:
A stretched single lambda DNA molecule labeled with TOTO-1 dye molecules was immobilized on a cover slip by casting a solution of DNA-lipid polyion complex containing TOTO-1 dye, and were loaded with an aqueous solution of histone. Fluorescence microscopy applied to the single DNA showed that (1) the TOTO-1 dye molecules intercalated in the stretched DNA molecule were vertically aligned almost completely with respect to the DNA axis, and (2) the stretched DNA was cleaved by interaction with histone molecules.

