6QIY

CI-2, conformation 1

Summary for 6QIY

• Entry DOI: 10.2210/pdb6qiy/pdb
• Descriptor: Subtilisin-chymotrypsin inhibitor-2A (2 entities in total)
• Functional Keywords: chymotrypsin inhibitor 2, protease inhibitor, plant protein
• Biological source: Hordeum vulgare (Barley)
• Total number of polymer chains: 1
• Total formula weight: 7411.66

Authors

Romero, A.,Ruiz, F.M. (deposition date: 2019-01-21, release date: 2019-12-25, Last modification date: 2024-01-24)

Primary citation

Campos, L.A.,Sharma, R.,Alvira, S.,Ruiz, F.M.,Ibarra-Molero, B.,Sadqi, M.,Alfonso, C.,Rivas, G.,Sanchez-Ruiz, J.M.,Romero Garrido, A.,Valpuesta, J.M.,Munoz, V.
Engineering protein assemblies with allosteric control via monomer fold-switching.
Nat Commun, 10:5703-5703, 2019

PubMed Abstract: The macromolecular machines of life use allosteric control to self-assemble, dissociate and change shape in response to signals. Despite enormous interest, the design of nanoscale allosteric assemblies has proven tremendously challenging. Here we present a proof of concept of allosteric assembly in which an engineered fold switch on the protein monomer triggers or blocks assembly. Our design is based on the hyper-stable, naturally monomeric protein CI2, a paradigm of simple two-state folding, and the toroidal arrangement with 6-fold symmetry that it only adopts in crystalline form. We engineer CI2 to enable a switch between the native and an alternate, latent fold that self-assembles onto hexagonal toroidal particles by exposing a favorable inter-monomer interface. The assembly is controlled on demand via the competing effects of temperature and a designed short peptide. These findings unveil a remarkable potential for structural metamorphosis in proteins and demonstrate key principles for engineering protein-based nanomachinery.

PubMed: 31836707
DOI: 10.1038/s41467-019-13686-1

Experimental method

X-RAY DIFFRACTION (1.5 Å)