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

Nat Chem. 2023 Jan;15(1):110-118. doi: 10.1038/s41557-022-01062-4. Epub 2022 Nov 7.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Esterases
  • Feedback
  • Nanotechnology*
  • Urease*

Substances

  • diazobenzenesulfonic acid
  • Urease
  • Esterases