Biomimetic artificial organelles with in vitro and in vivo activity triggered by reduction in microenvironment

• Published in: Nature communications 2018-03, Vol.9 (1), p.1127-12, Article 1127
• Main Authors: Einfalt, T., Witzigmann, D., Edlinger, C., Sieber, S., Goers, R., Najer, A., Spulber, M., Onaca-Fischer, O., Huwyler, J., Palivan, C. G.
• Format: Article
• Language: English
• Subjects: 101/58; 13; 13/31; 14/19; 14/28; 14/34; 14/63; 147/143; 147/28; 631/57/2272/2276; 639/638/298/54/989; 64/116; Amino Acid Substitution; Animals; Artificial Cells - metabolism; Biocatalysis; Bioengineering; Biomimetic Materials; Biomimetics; Biomolecules; Cellular Microenvironment - physiology; Embryos; Endogenous stimuli; Enzymatic activity; Enzymes; Feasibility studies; Genetic modification; Glutathione; HeLa Cells; Horseradish peroxidase; Humanities and Social Sciences; Humans; Membrane proteins; Molecular flow; multidisciplinary; Organelles; Organelles - enzymology; Peroxidase; Porins; Porins - chemistry; Porins - genetics; Porins - metabolism; Proteins; Recombinant Proteins - chemistry; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Science; Science (multidisciplinary); Stimuli; Surgical implants; Zebrafish; Zebrafish - embryology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-018-03560-x

Despite tremendous efforts to develop stimuli-responsive enzyme delivery systems, their efficacy has been mostly limited to in vitro applications. Here we introduce, by using an approach of combining biomolecules with artificial compartments, a biomimetic strategy to create artificial organelles (AOs) as cellular implants, with endogenous stimuli-triggered enzymatic activity. AOs are produced by inserting protein gates in the membrane of polymersomes containing horseradish peroxidase enzymes selected as a model for natures own enzymes involved in the redox homoeostasis. The inserted protein gates are engineered by attaching molecular caps to genetically modified channel porins in order to induce redox-responsive control of the molecular flow through the membrane. AOs preserve their structure and are activated by intracellular glutathione levels in vitro. Importantly, our biomimetic AOs are functional in vivo in zebrafish embryos, which demonstrates the feasibility of using AOs as cellular implants in living organisms. This opens new perspectives for patient-oriented protein therapy. The efficacy of stimuli-responsive enzyme delivery systems is usually limited to in vitro applications. Here the authors form artificial organelles by inserting stimuli-responsive protein gates in membranes of polymersomes loaded with enzymes and obtain a triggered functionality both in vitro and in vivo.