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This article has been peer reviewed. It is the authors' final version prior to publication in Structure, Volume 27, Issue 8, August 2019, Pages 1190-1191.

The published version is available at Copyright © Elsevier


The origin of protein backbone threading through a topological knot remains elusive. To understand the evolutionary origin of protein knots, in this issue of StructureKo et al. (2019) used circular permutation to untie a knotted protein. They showed that a domain-swapped dimer releases the knot and the associated high-energy state for substrate binding.

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Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

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