Open AccessSingle Molecule DNA Biophysics with Atomic Force Microscopy
Author(s) -
Anselmetti Dario,
Fritz Jürgen,
Smith Benjamin,
FernandezBusquets Xavier
Publication year - 2000
Publication title -
single molecules
Language(s) - English
Resource type - Journals
eISSN - 1438-5171
pISSN - 1438-5163
DOI - 10.1002/(sici)1438-5171(200004)1:1<53::aid-simo53>3.0.co;2-u
Subject(s) - force spectroscopy , dna , ethidium bromide , biophysics , molecule , atomic force microscopy , chemistry , crystallography , endonuclease , dna clamp , base pair , single molecule experiment , nanotechnology , materials science , biochemistry , biology , rna , reverse transcriptase , organic chemistry , gene
Structural and functional properties of double stranded deoxyribonucleic acid (dsDNA) are investigated by atomic force microscopy (AFM) on a single molecule level. Here, we characterize different linear and circular DNA systems in terms of their geometry and topology, and visualize enzyme binding of restriction endonuclease Hae III to DNA. Manipulation of single DNA molecules is demonstrated by dissecting individual DNA strands. Furthermore, the elastic response of single DNA molecules to an externally applied force is investigated by AFM force spectroscopy experiments. This gives information about structural properties of the DNA double helix. Specifically, transition from B‐form to S‐form DNA and a melting transition from double stranded to single stranded DNA is observed. This allows monitoring of specific interaction and binding of small intercalator molecules such as ethidium bromide (EtBr) to DNA by means of a mechanical, non‐fluorescent detection scheme.