Photoswitchable gating of non-equilibrium enzymatic feedback in chemically communicating polymersome nanoreactors

Journal article

The circadian rhythm generates out-of-equilibrium metabolite oscillations that are controlled by feedback loops under light/dark cycles. Here we describe a non-equilibrium nanosystem comprising a binary population of enzyme-containing polymersomes capable of light-gated chemical communication, controllable feedback and coupling to macroscopic oscillations. The populations consist of esterase-containing polymersomes functionalized with photo-responsive donor-acceptor Stenhouse adducts (DASA) and light-insensitive semipermeable urease-loaded polymersomes. The DASA-polymersome membrane becomes permeable under green light, switching on esterase activity and decreasing the pH, which in turn initiates the production of alkali in the urease-containing population. A pH-sensitive pigment that absorbs green light when protonated provides a negative feedback loop for deactivating the DASA-polymersomes. Simultaneously, increased alkali production deprotonates the pigment, reactivating esterase activity by opening the membrane gate. We utilize light-mediated fluctuations of pH to perform non-equilibrium communication between the nanoreactors and use the feedback loops to induce work as chemomechanical swelling/deswelling oscillations in a crosslinked hydrogel. We envision possible applications in artificial organelles, protocells and soft robotics

Authors: Rifaie-Graham, O; Yeow, J; Najer, A; Wang, R; Sun, R

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Nature Research
• Journal: Nature Chemistry
• Volume: 15
• Issue: 1
• Pages: 110-118
• Publication date: 2022-11-07
• DOI: 10.1038/s41557-022-01062-4
• EISSN: 1755-4349
• ISSN: 1755-4330
• Language: English
• Keywords: Amphiphile; Nanoreactor; Population; Organic chemistry; Membrane; Polymersome; Materials science; Nanotechnology; Combinatorial chemistry; Biophysics; Protocell; Copolymer; Biochemistry; Chemistry