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Visualization of unstained DNA nanostructures with advanced in-focus phase contrast TEM techniques.

ABSTRACT: Over the last few years, tremendous progress has been made in visualizing biologically important macromolecules using transmission electron microscopy (TEM) and understanding their structure-function relation. Yet, despite the importance of DNA in all forms of life, TEM visualization of individual DNA molecules in its native unlabeled form has remained extremely challenging. Here, we present high-contrast images of unstained single-layer DNA nanostructures that were obtained using advanced in-focus phase contrast TEM techniques. These include sub-Ångstrom low voltage electron microscopy (SALVE), the use of a volta-potential phase plate (VPP), and dark-field (DF) microscopy. We discuss the advantages and drawbacks of these techniques for broad applications in structural biology and materials science.

SUBMITTER: Kabiri Y

PROVIDER: S-EPMC6510773 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Visualization of unstained DNA nanostructures with advanced in-focus phase contrast TEM techniques.

Kabiri Yoones Y Ravelli Raimond B G RBG Lehnert Tibor T Qi Haoyuan H Katan Allard J AJ Roest Natascha N Kaiser Ute U Dekker Cees C Peters Peter J PJ Zandbergen Henny H

Scientific reports 20190510 1

Over the last few years, tremendous progress has been made in visualizing biologically important macromolecules using transmission electron microscopy (TEM) and understanding their structure-function relation. Yet, despite the importance of DNA in all forms of life, TEM visualization of individual DNA molecules in its native unlabeled form has remained extremely challenging. Here, we present high-contrast images of unstained single-layer DNA nanostructures that were obtained using advanced in-fo ...[more]

PMID: 31076614

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