Enzymatic Reactions Convectively Aggregate Microcapsules Modeling Self-assembly of Protocells

Scientific Achievement

We discovered that reactions catalyzed by surface-bound enzymes generate fluid flow, causing reagent-laden microcapsules to aggregate.

Significance and Impact

These results provide a simple and robust mechanism for self-organization of early biological cells consisting of interior and enveloping membrane.

Simulated convective aggregation of capsules (blue) driven by enzymatic decomposition of hydrogen peroxide. Convective vortexes (arrows) assemble capsules above enzyme-coated patch (green).

Research Details

  • Fueled by reagent diffusing out of capsules through porous shell
  • Relies on convective flows generated by fluid density variations due to chemical reactions catalyzed on surfaces of microchannel
  • Forms colony above enzyme-coated region after reagent is consumed and convection stops
  • O.E. Shklyaev, H. Shum, A. Sen, A.C. Balazs, Sci. Adv. 2016; 2:e1501835 18 March 2016

Work performed at the University of Pittsburgh. This work was supported by the Center for Bio-Inspired Energy Science (for the computational studies) and the Charles E. Kaufman Foundation (for the development of the theoretical model).