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bioRxiv · 10.1101/2024.06.13.598841

Di-Gluebodies as covalently-rigidified, modular protein assemblies enable simultaneous determination of high-resolution, low-size, cryo-EM structures

Yi, G.·Mamalis, D.·Ye, M.·Carrique, L.·Fairhead, M.·Li, H.·Duerr, K. L.·Zhang, P.·Sauer, D. B.·von Delft, F.·Davis, B. G.·Gilbert, R. J. C.
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Abstract

Cryo-EM has become a routine structural biology method, yet elucidation of small proteins (<100 kDa) and increasing throughput remain challenging. Here, we describe covalently-dimerized engineered nanobodies, Di-Gluebodies, as novel and modular imaging scaffolds to address the challenges. They can simultaneously display two copies of the same protein or two distinct proteins, providing sufficient rigidity required by cryo-EM. We validate this method with multiple soluble and membrane targets, demonstrating that this provides a flexible and scalable platform for expanded protein structure determination.

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Yi, G., Mamalis, D., Ye, M., Carrique, L., Fairhead, M., Li, H., Duerr, K. L., Zhang, P., Sauer, D. B., von Delft, F., Davis, B. G., Gilbert, R. J. C.. 2024-06-13. Di-Gluebodies as covalently-rigidified, modular protein assemblies enable simultaneous determination of high-resolution, low-size, cryo-EM structures. https://doi.org/10.1101/2024.06.13.598841

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