Living cells segregate molecules and reactions in various subcellular compartments known as organelles. Spatial organization is likely essential for expanding the biochemical functions of synthetic reaction systems, including artificial cells. Many studies have attempted to mimic organelle functions using lamellar membrane-bound vesicles. However, vesicles typically suffer from highly limited transport across the membranes and an inability to mimic the dense membrane networks typically found in organelles such as the endoplasmic reticulum. Here, we describe programmable synthetic organelles based on highly stable nonlamellar sponge phase droplets that spontaneously assemble from a single-chain galactolipid and nonionic detergents. Due to their nanoporous structure, lipid sponge droplets readily exchange materials with the surrounding environment. In addition, the sponge phase contains a dense network of lipid bilayers and nanometric aqueous channels, which allows different classes of molecules to partition based on their size, polarity, and specific binding motifs. The sequestration of biologically relevant macromolecules can be programmed by the addition of suitably functionalized amphiphiles to the droplets. We demonstrate that droplets can harbor functional soluble and transmembrane proteins, allowing for the colocalization and concentration of enzymes and substrates to enhance reaction rates. Droplets protect bound proteins from proteases, and these interactions can be engineered to be reversible and optically controlled. Our results show that lipid sponge droplets permit the facile integration of membrane-rich environments and self-assembling spatial organization with biochemical reaction systems.
Nucleic acids are among the most versatile molecules for the construction of biomimetic systems because they can serve as information carriers and programmable construction materials. How nucleic acids interact with coacervate compartments that consist of a lipid sponge phase is not known. Here we systematically characterize the potential of DNA to functionalize lipid sponge droplets and demonstrate a strong size dependence for sequestration into the sponge phase. Double stranded DNA molecules of more than 300 bp are excluded and form a corona on the surface of droplets they are targeted to. Shorter DNA molecules partition efficiently into the lipid sponge phase and can direct DNA‐templated reactions to droplets. We demonstrate repeated capture and release of labeled DNA strands by dynamic hybridization and strand displacement reactions that occur inside droplets. Our system opens new opportunities for DNA‐encoded functions in lipid sponge droplets such as cargo control and signaling.
more » « less- NSF-PAR ID:
- 10366936
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSystemsChem
- Volume:
- 4
- Issue:
- 3
- ISSN:
- 2570-4206
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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