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Mapping Single-Molecule Protein Complexes in 3D with DNA Nanoswitch Calipers.

ABSTRACT: The ability to accurately map the 3D geometry of single-molecule complexes in trace samples is a challenging goal that would lead to new insights into molecular mechanics and provide an approach for single-molecule structural proteomics. To enable this, we have developed a high-resolution force spectroscopy method capable of measuring multiple distances between labeled sites in natively folded protein complexes. Our approach combines reconfigurable nanoscale devices, we call DNA nanoswitch calipers, with a force-based barcoding system to distinguish each measurement location. We demonstrate our approach by reconstructing the tetrahedral geometry of biotin-binding sites in natively folded streptavidin, with 1.5-2.5 Å agreement with previously reported structures.

SUBMITTER: Shrestha P

PROVIDER: S-EPMC10755700 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Mapping Single-Molecule Protein Complexes in 3D with DNA Nanoswitch Calipers.

Shrestha Prakash P Yang Darren D Ward Andrew A Shih William M WM Wong Wesley P WP

Journal of the American Chemical Society 20231214 51

The ability to accurately map the 3D geometry of single-molecule complexes in trace samples is a challenging goal that would lead to new insights into molecular mechanics and provide an approach for single-molecule structural proteomics. To enable this, we have developed a high-resolution force spectroscopy method capable of measuring multiple distances between labeled sites in natively folded protein complexes. Our approach combines reconfigurable nanoscale devices, we call DNA nanoswitch calip ...[more]

PMID: 38096567

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