AI Insight
Researchers developed a method to release proteins from synthetic cells using osmotic pressure generated internally rather than relying on membrane pores. They encapsulated a cell-free protein expression system in polymer vesicles that simultaneously produced a fluorescent protein and an enzyme that breaks down dextran polymers into smaller sugars. The enzymatic breakdown of dextran increased osmotic pressure inside the vesicles, causing them to expand and release up to 78-82% of the internal protein cargo without visible membrane rupture.
Why it matters
This approach could enable more controlled drug delivery systems and improve synthetic cell designs by allowing release of therapeutic proteins or other large molecules without engineering dedicated pore proteins into membranes. The method demonstrates a new way to couple gene expression with mechanical actuation in artificial cells, potentially useful for biotechnology and synthetic biology applications.
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⚠️ Preprint – Noch nicht peer-reviewed
Dieser Artikel wurde noch nicht von unabhängigen Experten begutachtet. Die Ergebnisse sind vorläufig und sollten mit Vorsicht interpretiert werden.
Macromolecular release from synthetic cells often relies on membrane pores or channels. We explored whether internally generated osmotic stress could increase membrane permeability and promote release. Using double-emulsion microfluidics, we encapsulated an Escherichia coli cell-free expression system in Pluronic L121 polymersomes to co-express the fluorescent protein mScarlet3 and the dextranase PsDex1711 in the presence of dextran. PsDex1711-mediated dextran hydrolysis produced a greater increase in bulk osmolality than reactions without PsDex1711 DNA. Tracking hundreds of individual polymersomes showed that PsDex1711-containing populations expanded, whereas control populations contracted. The distribution of normalized fluorescence revealed a subset with lower residual fluorescence than the main population. In selected expanded polymersomes, integrated internal mScarlet3 fluorescence declined to 18-22% of peak levels, without visible membrane disruption, consistent with protein release. These findings support a proof of concept for using internal gene expression to promote macromolecular release through osmotic actuation without introducing dedicated membrane pores.
Source: Releasing Protein Cargo from Synthetic Cells by Coupling Cell-Free Expression to Osmotic Actuation