7MN1

Rules for designing protein fold switches and their implications for the folding code

Summary for 7MN1

• Entry DOI: 10.2210/pdb7mn1/pdb
• NMR Information: BMRB: 30901
• Descriptor: Sa1 (1 entity in total)
• Functional Keywords: protein fold switching, metamorphic proteins, design, fold evolution, structural biology, de novo protein, artificially designed
• Biological source: Thermus thermophilus
• Total number of polymer chains: 1
• Total formula weight: 10600.33

Authors

He, Y.,Chen, Y.,Ruan, B.,Choi, J.,Chen, Y.,Motabar, D.,Solomon, T.,Simmerman, R.,Kauffman, T.,Gallagher, T.,Bryan, P.,Orban, J. (deposition date: 2021-04-30, release date: 2022-05-18, Last modification date: 2024-05-15)

Primary citation

Ruan, B.,He, Y.,Chen, Y.,Choi, E.J.,Chen, Y.,Motabar, D.,Solomon, T.,Simmerman, R.,Kauffman, T.,Gallagher, D.T.,Orban, J.,Bryan, P.N.
Design and characterization of a protein fold switching network.
Nat Commun, 14:431-431, 2023

PubMed Abstract: To better understand how amino acid sequence encodes protein structure, we engineered mutational pathways that connect three common folds (3α, β-grasp, and α/β-plait). The structures of proteins at high sequence-identity intersections in the pathways (nodes) were determined using NMR spectroscopy and analyzed for stability and function. To generate nodes, the amino acid sequence encoding a smaller fold is embedded in the structure of an ~50% larger fold and a new sequence compatible with two sets of native interactions is designed. This generates protein pairs with a 3α or β-grasp fold in the smaller form but an α/β-plait fold in the larger form. Further, embedding smaller antagonistic folds creates critical states in the larger folds such that single amino acid substitutions can switch both their fold and function. The results help explain the underlying ambiguity in the protein folding code and show that new protein structures can evolve via abrupt fold switching.

PubMed: 36702827
DOI: 10.1038/s41467-023-36065-3

Experimental method

SOLUTION NMR