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Enzyme-Free Phosphorylation with Kinetic Gating in a De Novo Coiled-Coil System
Simone M Poprawa1, Niklas L Hoja2, Clara Hipp1
1Department of Bioscience, School of Natural Sciences, Technical University of Munich, Lichtenbergstrasse 4, Garching 85748, Germany.
Journal of the American Chemical Society
|May 19, 2026
Summary
Researchers developed enzyme-free phosphorylation to control peptide assembly. This synthetic cycle mimics molecular motors by using phosphorylation to regulate coiled-coil formation and disassembly.
Area of Science:
- Biochemistry
- Synthetic Biology
- Biophysics
Background:
- Phosphorylation is a critical posttranslational modification regulating biological processes.
- Enzymatic networks tightly control phosphorylation, making enzyme-free systems challenging to design.
- Understanding non-enzymatic regulation is key for developing artificial molecular machines.
Purpose of the Study:
- To investigate enzyme-free phosphorylation in a designed peptide system.
- To modulate coiled-coil (CC) assembly and dynamics using synthetic phosphorylation.
- To establish a minimal synthetic phosphorylation cycle mimicking molecular motor functions.
Main Methods:
- Designed a peptide system with a histidine residue in an alpha-helix.
- Utilized a nonbiological reaction cycle for phosphorylation and dephosphorylation.
- Analyzed the kinetics of dephosphorylation in assembled versus nonassembled states.
Main Results:
- Achieved enzyme-free phosphorylation to control CC assembly and dynamics.
- Demonstrated that dephosphorylation is significantly faster (25x) in the assembled CC state.
- Established a ratcheted cycle of phosphorylation, CC formation, dephosphorylation, and disassembly.
- The synthetic cycle performs work, mimicking molecular motors.
Conclusions:
- Enzyme-free phosphorylation can effectively regulate peptide assembly and dynamics.
- The designed system provides a minimal model for molecular motors, walkers, and pumps.
- This work offers design principles for synthetic biological systems and artificial molecular machines.
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