posted on 2023-12-14, 22:29authored byPrakash Shrestha, Darren Yang, Andrew Ward, William M. Shih, Wesley P. Wong
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.