Antagonistic chemical coupling in self-reconfigurable host\u2013guest protocells

Nicolas Martin,Mei Li,Richard Booth,Stephen Mann,Yan Qiao,Jean-Paul Douliez

doi:10.1038/s41467-018-06087-3

Abstract

Fabrication of compartmentalised chemical systems with nested architectures and biomimetic properties has important implications for controlling the positional assembly of functional components, spatiotemporal regulation of enzyme cascades and modelling of proto-organelle behaviour in synthetic protocells. Here, we describe the spontaneous capture of glucose oxidase-containing proteinosomes in pH-sensitive fatty acid micelle coacervate droplets as a facile route to multi-compartmentalised host–guest protocells capable of antagonistic chemical and structural coupling. The nested system functions co-operatively at low-substrate turnover, while high levels of glucose give rise to pH-induced disassembly of the droplets, release of the incarcerated proteinosomes and self-reconfiguration into spatially organised enzymatically active vesicle-in-proteinosome protocells. Co-encapsulation of antagonistic enzymes within the proteinosomes produces a sequence of self-induced capture and host–guest reconfiguration. Taken together, our results highlight opportunities for the fabrication of self-reconfigurable host–guest protocells and provide a step towards the development of protocell populations exhibiting both synergistic and antagonistic modes of interaction.

Highlights

Fabrication of compartmentalised chemical systems with nested architectures and biomimetic properties has important implications for controlling the positional assembly of functional components, spatiotemporal regulation of enzyme cascades and modelling of protoorganelle behaviour in synthetic protocells
The hybrid constructs consist of two primary protocell types arranged in a nested microstructure derived from the spontaneous capture and confinement of glucose oxidase (GOx)-containing guest proteinosomes within individual horseradish peroxidase (HRP)-containing fatty acid micelle coacervate host micro-droplets
Non-fluorescent proteinosomes loaded with fluorescein isothiocyanate (FITC)-labelled GOx exhibited a uniform green fluorescence throughout their interior (Supplementary Fig. 2), which was consistent with the retention and homogeneous distribution of the entrapped enzyme

Summary

Introduction

Fabrication of compartmentalised chemical systems with nested architectures and biomimetic properties has important implications for controlling the positional assembly of functional components, spatiotemporal regulation of enzyme cascades and modelling of protoorganelle behaviour in synthetic protocells. We describe the spontaneous capture of glucose oxidase-containing proteinosomes in pH-sensitive fatty acid micelle coacervate droplets as a facile route to multi-compartmentalised host–guest protocells capable of antagonistic chemical and structural coupling. The fabrication of nested compartments involving different types of protocells capable of being dynamically restructured to produce higherorder behaviours has received little attention In this regard, the investigation of collective properties in synthetic protocell populations is an emerging paradigm that has recently been exploited for the design and conception of artificial predatoryprey[45] and phagocytosis-inspired[39] behaviours. Our results highlight opportunities for the spontaneous construction of self-reconfigurable host–guest protocells, and provide a step towards the development of protocell populations exhibiting both synergistic and antagonistic modes of interaction

Methods

Results

Conclusion