A photosynthesis-driven biophotovoltaic system with an Al-anode powered a microprocessor widely used in IoT applications stably for over six months.

Synthetic biology research and its industrial applications rely on the deterministic spatiotemporal control of gene expression. Recently, electrochemical control of gene expression has been demonstrated in electrogenetic systems (redox-responsive promoters used alongside redox inducers and an electrode), allowing for the direct integration of electronics with complex biological processes for a variety of new applications. However, the use of electrogenetic systems is limited by poor activity, tunability and standardisation. Here, we have developed a variety of genetic and electrochemical tools that facilitate the design and vastly improve the performance of electrogenetic systems. We developed a strong, unidirectional, redox-responsive promoter before deriving a mutant promoter library with a spectrum of strengths. We then constructed genetic circuits with these parts and demonstrated their activation by multiple classes of redox molecules. Finally, we demonstrated electrochemical activation of gene expression in aerobic conditions utilising a novel, modular bioelectrochemical device. This toolset provides researchers with all the elements needed to design and build optimised electrogenetic systems for specific applications.

Peridinin-containing dinoflagellate algae have a chloroplast genome formed from plasmid-like minicircles. This fragmented genome has allowed us to develop a genetic modification methodology involving the use of biolistics to introduce artificial minicircles inAmphidinium carterae(Nimmo et al., 2019). The previously reported artificial minicircles were based on native minicircles containing either thepsbAoratpBgene. Each artificial minicircle allowed expression of a single selectable marker instead ofpsbAoratpB. Here, we present two further artificial minicircles for use in transformation ofA. carterae. One is based on thepetDminicircle, allowing the expression of a single selectable marker. The second is based on the two-gene minicircle originally containingatpAandpetB, and allows the dual expression of a selectable marker and a gene of interest. Our research suggest that all of the 20 or so minicircles inA. carteraeare suitable for adaptation as artificial minicircles, allowing for the simultaneous introduction of multiple genes.

In the framework of resource-competition models, it has been argued that the number of species stably coexisting in an ecosystem cannot exceed the number of shared resources. However, plankton seems to be an exception of this so-called "competitive-exclusion principle". In planktic ecosystems, a large number of different species stably coexist in an environment with limited resources. This contradiction between theoretical expectations and empirical observations is often referred to as "The Paradox of the Plankton". This project aims to investigate biophysical models that can account for the large biodiversity observed in real ecosystems in order to resolve this paradox. A model is proposed that combines classical resource competition models, metabolic trade-offs and stochastic ecosystem assembly. Simulations of the model match empirical observations, while relaxing some unrealistic assumptions from previous models.