Mapping mechanical force propagation through biomolecular complexes

Schoeler, Constantin; Bernardi, Rafael C.; Malinowska, Klara H.; Durner, Ellis; Ott, Wolfgang; Bayer, Edward A.; Schulten, Klaus; Nash, Michael A.; Gaub, Hermann E.

doi:10.1021/acs.nanolett.5b02727

DOE OSTI · 1345019

Mapping mechanical force propagation through biomolecular complexes

Schoeler, Constantin·Bernardi, Rafael C.·Malinowska, Klara H.·Durner, Ellis·Ott, Wolfgang·Bayer, Edward A.·Schulten, Klaus·Nash, Michael A.·Gaub, Hermann E.

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Abstract

In this paper, we employ single-molecule force spectroscopy with an atomic force microscope (AFM) and steered molecular dynamics (SMD) simulations to reveal force propagation pathways through a mechanically ultrastable multidomain cellulosome protein complex. We demonstrate a new combination of network-based correlation analysis supported by AFM directional pulling experiments, which allowed us to visualize stiff paths through the protein complex along which force is transmitted. Finally, the results implicate specific force-propagation routes nonparallel to the pulling axis that are advantageous for achieving high dissociation forces.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY 59 BASIC BIOLOGICAL SCIENCES cohesin−dockerin force propagation network analysis single molecule force spectroscopy steered molecular dynamics

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Schoeler, Constantin, Bernardi, Rafael C., Malinowska, Klara H., Durner, Ellis, Ott, Wolfgang, Bayer, Edward A., Schulten, Klaus, Nash, Michael A., Gaub, Hermann E.. 2015-08-11. Mapping mechanical force propagation through biomolecular complexes. https://doi.org/10.1021/acs.nanolett.5b02727

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