Phase Transitions in Chemically Fueled, Multiphase Complex Coacervate Droplets

• Published in: Angewandte Chemie International Edition Vol. 61; no. 46; pp. e202211905 - n/a
• Main Authors: Donau, Carsten, Späth, Fabian, Stasi, Michele, Bergmann, Alexander M., Boekhoven, Job
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 14.11.2022; John Wiley and Sons Inc
• Edition: International ed. in English
• Subjects: Chemical reactions; Chemically Fueled; Complex Coacervation; Cytosol; Droplets; Kinetics; Liquidity; Membraneless Organelles; Multiphase Droplets; Organelles; Peptides; Phase diagrams; Phase Transitions; Polyanions; Polyelectrolytes; Thermodynamic properties; Multiphase Droplets; Chemically Fueled; Membraneless Organelles; Complex Coacervation; Phase Transitions
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202211905

Membraneless organelles are droplets in the cytosol that are regulated by chemical reactions. Increasing studies suggest that they are internally organized. However, how these subcompartments are regulated remains elusive. Herein, we describe a complex coacervate‐based model composed of two polyanions and a short peptide. With a chemical reaction cycle, we control the affinity of the peptide for the polyelectrolytes leading to distinct regimes inside the phase diagram. We study the transitions from one regime to another and identify new transitions that can only occur under kinetic control. Finally, we show that the chemical reaction cycle controls the liquidity of the droplets offering insights into how active processes inside cells play an important role in tuning the liquid state of membraneless organelles. Our work demonstrates that not only thermodynamic properties but also kinetics should be considered in the organization of multiple phases in droplets. Coupling multiphase coacervate droplets to a chemical reaction cycle allows access to regimes inside the phase diagram not possible under thermodynamic control. Control over the stability, liquidity, and localization of the multiphases makes it a great synthetic platform to study the organization of membraneless organelles.