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Biomechanics of DNA structures visualized by 4D electron microscopy.

ABSTRACT: We present a technique for in situ visualization of the biomechanics of DNA structural networks using 4D electron microscopy. Vibrational oscillations of the DNA structure are excited mechanically through a short burst of substrate vibrations triggered by a laser pulse. Subsequently, the motion is probed with electron pulses to observe the impulse response of the specimen in space and time. From the frequency and amplitude of the observed oscillations, we determine the normal modes and eigenfrequencies of the structures involved. Moreover, by selective "nano-cutting" at a given point in the network, it was possible to obtain Young's modulus, and hence the stiffness, of the DNA filament at that position. This experimental approach enables nanoscale mechanics studies of macromolecules and should find applications in other domains of biological networks such as origamis.

SUBMITTER: Lorenz UJ

PROVIDER: S-EPMC3581949 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Biomechanics of DNA structures visualized by 4D electron microscopy.

Lorenz Ulrich J UJ Zewail Ahmed H AH

Proceedings of the National Academy of Sciences of the United States of America 20130204 8

We present a technique for in situ visualization of the biomechanics of DNA structural networks using 4D electron microscopy. Vibrational oscillations of the DNA structure are excited mechanically through a short burst of substrate vibrations triggered by a laser pulse. Subsequently, the motion is probed with electron pulses to observe the impulse response of the specimen in space and time. From the frequency and amplitude of the observed oscillations, we determine the normal modes and eigenfreq ...[more]

PMID: 23382239

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