Harnessing Bioluminescent Bacteria to Power Photochemical Transformations

The use of light energy to promote chemical reactions is one of the most vibrant and versatile areas of current research. In particular, visible light photocatalysis allows for the selective excitation of a specific molecule, which is then able to undergo energy or electron transfer with a reagent. This is a powerful strategy to form catalytic quantities of highly reactive intermediates, such as radicals or carbenes, in a highly selective manner. A vast array of novel reactions and new molecules have been generated using this approach. However, despite its widespread use in academic and industrial labs its application in large-scale multi-tonne reactions has not been realised.

This can be rationalised by the poor scalability of many photochemical methods. The main factor attributed to this is the attenuation of light as described by the Beer-Lambert law. Simply increasing the scale of a reaction will drastically reduce its surface area and with light intensity decreasing exponentially within the vessel much of this energy is wasted.

In this project, we seek to utilise bioluminescent bacteria as a photon source to conduct photochemical transformations. Importantly, a range of fluorescent proteins, luminescent marine and soil microorganisms are readily available; therefore, providing access to a variety of wavelengths of visible light. Initial studies will focus on obtaining proof-of-concept using a chemical photoredox reaction with a focus on biocompatibility. We will assess the biological response of the organism to the presence of photochemical intermediates (via transcriptomics) in addition to using modern synthetic biology approaches to tune the intensity and wavelength of the bioluminescence to create a modular, genetic approach to the cellular generation of light for a range of photochemical reactions.

Overall, the successful implementation of this strategy will offer a new method for powering photochemical transformations without a high-powered light source. This less energy intensive approach will assist the adoption of these reactions on manufacturing scales by cutting both costs and harmful emissions.