Engineering cellular communication between light-activated synthetic cells and bacteria

Abstract

Gene-expressing compartments assembled from simple, modular parts, are a versatile platform for creating minimal synthetic cells with life-like functions. By incorporating gene regulatory motifs into their encapsulated DNA templates, in situ gene expression and, thereby, synthetic cell function can be controlled according to specific stimuli. In this work, cell-free protein synthesis within synthetic cells was controlled using light by encoding genes of interest on light-activated DNA templates. Light-activated DNA contained a photocleavable blockade within the T7 promoter region that tightly repressed transcription until the blocking groups were removed with ultraviolet light. In this way, synthetic cells were activated remotely, in a spatiotemporally controlled manner. By applying this strategy to the expression of an acyl homoserine lactone synthase, BjaI, quorum-sensing-based communication between synthetic cells and bacteria was controlled with light. This work provides a framework for the remote-controlled production and delivery of small molecules from nonliving matter to living matter, with applications in biology and medicine.

Sequence-independent, site-specific incorporation of chemical modifications to generate light-activated plasmids

“…We believe these controllable plasmids might be especially relevant for studies in developmental biology 26,27 and population dynamics. 60…”

Lipid vesicle-based molecular robots

“…Quorum sensing, which is the communication behavior of cells to detect and respond to cell population density, has been extended to molecular robots and bacterial populations. 327–329 Remarkably, Smith et al reported light-activated GUVs that could perform quorum-sensing-based communication with bacteria 329 (Fig. 13(c)).…”

Models of Chemical Communication for Micro/Nanoparticles

“…Communication can also be engineered using a synthetic biology approach, based on the expression of proteins inside vesicles by means of transcription-translation (TXTL) reactions. , In these reactions, protein synthesis machinery is encapsulated together with the DNA sequences encoding the proteins of interest. Upon rational design of the plasmid, protein expression can be activated in the presence of certain species (such as membrane-permeable quorum sensing molecules) or upon application of light . Then, the in situ expressed proteins can either form pores on the membrane to induce the release of entrapped cargo or catalyze certain reactions to produce chemical messengers. , …”

“…In more recent work, Mansy’s group established communication between GUV-based artificial cells and eukaryotic cells (kidney or neural) via the release of brain-derived neurotrophic factor (BDNF) upon addition of external 3O6CHSL, producing protein expression or neural differentiation as a result . Other groups have employed TXTL machinery for constitutive (without external input addition) or light-controlled expression of different enzymes in GUVs, which subsequently catalyze the production of membrane-permeable gene inducers as chemical messengers to communicate with bacteria (that trigger the expression of fluorescent proteins as a response) …”