posted on 2023-12-19, 06:03authored bySamuel Kim, Marcus V. J. Cathey, Brandon
C. Bounds, Zackary Scholl, Piotr E. Marszalek, Minkyu Kim
Protein self-assembly plays a vital role in a myriad
of biological
functions and in the construction of biomaterials. Although the physical
association underlying these assemblies offers high specificity, the
advantage often compromises the overall durability of protein complexes.
To address this challenge, we propose a novel strategy that reinforces
the molecular self-assembly of protein complexes mediated by their
ligand. Known for their robust noncovalent interactions with biotin,
streptavidin (SAv) tetramers are examined to understand how the ligand
influences the mechanical strength of protein complexes at the nanoscale
and macroscale, employing atomic force microscopy-based single-molecule
force spectroscopy, rheology, and bioerosion analysis. Our study reveals
that biotin binding enhances the mechanical strength of individual
SAv tetramers at the nanoscale. This enhancement translates into improved
shear elasticity and reduced bioerosion rates when SAv tetramers are
utilized as cross-linking junctions within hydrogel. This approach,
which enhances the mechanical strength of protein-based materials
without compromising specificity, is expected to open new avenues
for advanced biotechnological applications, including self-assembled,
robust biomimetic scaffolds and soft robotics.