Engineered cell-to-cell signalling within growing bacterial cellulose pellicles

Abstract

Bacterial cellulose is a strong and flexible biomaterial produced at high yields by Acetobacter species and has applications in healthcare, biotechnology and electronics. Naturally, bacterial cellulose grows as a large unstructured polymer network around the bacteria that produce it, and tools to enable these bacteria to respond to different locations are required to grow more complex structured materials. Here, we introduce engineered cell-to-cell communication into a bacterial cellulose-producing strain of Komagataeibacter rhaeticus to enable different cells to detect their proximity within growing material and trigger differential gene expression in response. Using synthetic biology tools, we engineer Sender and Receiver strains of K.rhaeticus to produce and respond to the diffusible signalling molecule, acyl-homoserine lactone (AHL). We demonstrate that communication can occur both within and between growing pellicles and use this in a boundary detection experiment, where spliced and joined pellicles sense and reveal their original boundary. This work sets the basis for synthetic cellto-cell communication within bacterial cellulose and is an important step forward for pattern formation within engineered living materials.

Engineered Living Materials: Taxonomies and Emerging Trends

“…In recent years, primary advancements in applied ELM technologies have centered on nonmedical applications for design problems in other industries (e.g., electronics, construction, devices, and computing). Engineers have produced electrically conductive biofilms and advanced electrical biosensors using Curli fibers [45][46][47][48] and bacterial cellulose pellicles [49]. Examples of enabling technologies and proofs of concept also exist in the literature related to engineering living photovoltaics [50], electronics [51], and photonic materials [19].…”

Synthetic biology for the development of bio-based binders for greener construction materials

“…Recent work in the area of synthetic biology and the cellulose producing bacterium Komagataeibacter rhaeticus may lead to the production of patterned biological materials with unique properties in terms of macrostructure and function. Walker et al [66]. have engineered K. rhaeticus with genetic manipulation tools to insert synthetic circuits into the cellulose pathway which respond to intercellular signalling.…”

Towards control of cellulose biosynthesis by Komagataeibacter using systems-level and strain engineering strategies: current progress and perspectives

“…These studies together give a comprehensive guide for the construction of vectors of a high potential to be effective in the numerous species from this genus. These recent achievements include the use of quorum sensing (QS) synthetic biology elements known to be functional in E. coli (Florea et al 2016 ; Walker et al 2018 ). The first example of employment of these elements was the application of inducible lux promoter and luxR gene for modification of K. rhaeticus strain (Florea et al 2016 ).…”

“…This study showed that the capability of cellulose production was lowered and eventually switched off with increasing concentration of N -acyl homoserine lactone (AHL) in the media. Another study reported the construction of Sender and Receiver recombinant K. rhaeticus strains (Walker et al 2018 ). The first strain produced AHL in response to an environmental signal, while the second strain induced recombinant protein expression (red fluorescent protein, RFP) in response to AHL in a concentration-dependent manner.…”