De novo design of allosterically switchable protein assemblies

Area of Science:

• Protein Engineering
• Biophysics
• Synthetic Biology

Background:

• Allosteric modulation is crucial for biological regulation, controlling metabolism and cell signaling through distant conformational changes.
• Designing synthetic allosteric proteins that mimic natural systems' subtle, distributed conformational changes presents a significant challenge.

Purpose of the Study:

• To investigate the de novo design of allosteric systems using a novel approach based on rigid-body coupling.
• To create synthetic protein assemblies with effector-regulated functions.

Main Methods:

• Inspired by the Monod-Wyman-Changeux model, researchers coupled peptide-switchable hinge modules to protein interfaces.
• Techniques included size-exclusion chromatography, mass photometry, and electron microscopy to characterize designed assemblies.

Main Results:

• Successfully generated diverse allosteric systems, including cyclic rings and dihedral cages, with peptide-binding-induced assembly/disassembly.
• Designed protein assemblies accurately reflected models and exhibited ligand-binding cooperativity comparable to natural systems like hemoglobin.

Conclusions:

• Allostery can be achieved through global coupling of protein substructure energetics, not solely relying on optimized side-chain interactions.
• This work provides a framework for developing allosterically controlled delivery systems, protein nanomachines, and cellular feedback circuits.