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Artificial cell and organelle construction has recently gained substantial attention to generate simplified models for understanding of biological phenomena, or micro‐ and nanomachines for biomedical and biotechnological applications. A wide array of building blocks has been employed to build these systems as membraneless structures with the ability to compartmentalize chemical reactions by enhanced partitioning, or as membrane‐defined entities that provide a physical barrier that inhibits the interference of external factors. While these systems present unique properties that enable high fidelity to biological processes, they present limited ability to recreate the high selectivity and specificity of small molecule trafficking observed in biological membranes. Owing to their high chemical versatility, polymers can be leveraged to generate 3D structures that resemble biological membranes while providing transmembrane chemical motifs that enable responsiveness to a wide array of stimuli. This Concept Article discusses the ability to control membrane transport facilitating the emergence of out‐of‐equilibrium feedback mechanisms that ultimately modulate enzymatic rates. This can be employed to engineer future artificial cells and organelles that display homeostasis as a mechanism of self‐adaptation to continuously evolving environments. [ABSTRACT FROM AUTHOR]

Some marine plankton called dinoflagellates emit light in response to the movement of surrounding water, resulting in a phenomenon called milky seas or sea sparkle. The underlying concept, a shear‐stress induced permeabilisation of biocatalytic reaction compartments, is transferred to polymer‐based nanoreactors. Amphiphilic block copolymers that carry nucleobases in their hydrophobic block are self‐assembled into polymersomes. The membrane of the vesicles can be transiently switched between an impermeable and a semipermeable state by shear forces occurring in flow or during turbulent mixing of polymersome dispersions. Nucleobase pairs in the hydrophobic leaflet separate when mechanical force is applied, exposing their hydrogen bonding motifs and therefore making the membrane less hydrophobic and more permeable for water soluble compounds. This polarity switch is used to release payload of the polymersomes on demand, and to activate biocatalytic reactions in the interior of the polymersomes. [ABSTRACT FROM AUTHOR]