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Winding single-molecule double-stranded DNA on a nanometer-sized reel.

ABSTRACT: A molecular system of a nanometer-sized reel was developed from F(1)-ATPase, a rotary motor protein. By combination with magnetic tweezers and optical tweezers, single-molecule double-stranded DNA (dsDNA) was wound around the molecular reel. The bending stiffness of dsDNA was determined from the winding tension (0.9-6.0 pN) and the diameter of the wound loop (21.4-8.5?nm). Our results were in good agreement with the conventional worm-like chain model and a persistence length of 54?±?9?nm was estimated. This molecular reel system offers a new platform for single-molecule study of micromechanics of sharply bent DNA molecules and is expected to be applicable to the elucidation of the molecular mechanism of DNA-associating proteins on sharply bent DNA strands.

SUBMITTER: You H

PROVIDER: S-EPMC3479166 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Winding single-molecule double-stranded DNA on a nanometer-sized reel.

You Huijuan H Iino Ryota R Watanabe Rikiya R Noji Hiroyuki H

Nucleic acids research 20120705 19

A molecular system of a nanometer-sized reel was developed from F(1)-ATPase, a rotary motor protein. By combination with magnetic tweezers and optical tweezers, single-molecule double-stranded DNA (dsDNA) was wound around the molecular reel. The bending stiffness of dsDNA was determined from the winding tension (0.9-6.0 pN) and the diameter of the wound loop (21.4-8.5 nm). Our results were in good agreement with the conventional worm-like chain model and a persistence length of 54 ± 9 nm was est ...[more]

PMID: 22772992

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