Tripping the light fantastic: elucidating global protein structural change correlated with chemical change across the femtosecond to second timescale

At the heart of chemistry lies the process of atomic bond formation and breakage, an event that is very difficult to directly observe due to the extremely fast timescale and the very small nature of the atomic bond. In other words, the construction of a 'molecular camera' that might allow the recording of these fast and tiny events only recently become a reality. The advent of X-FEL (X-ray Free Electron Laser) systems has made the recording of such molecular movies a reality, although this remains an extremely technically challenging feat to achieve. Systems where atomic bond reorganisation is trigger by light are ideally suited as initial subjects for these cutting-edge studies as the researcher (ie the camera man) can control the event through (laser) illumination. We seek to determine how two distinct type of biological photoreceptors respond to light, coupling the initial atomic bond reorganisation to the transient change in protein structure that ulimately leads to a light-driven response by the organism. This will allow us to formulate new models for general protein dynamic behaviour, which will impact the areas of biocatalysis, biomaterials, therapeutic antibodies/protein production and the study of protein dynamic behaviour/misfolding in health and disease. Ultimately, the full characterisation of these photoreceptors will be combined with the rational engineering of these systems to produce a range of variants in terms of their response to light of various wavelenghts/colour. This will produce well-characterised light-responsive parts for control of bio-based production of high-value chemicals. The most desirable way to assert this control is through optogenetics: by using light as a non-invasive and non-toxic switch to modulate gene expression during continuous microbial fermentation, simple control of engineered biosynthetic pathways can be achieved.

The major non-academic beneficiaries are multiple.

The work will generate new photo responsive 'Parts' for the engineering of biology in a wide range of potential applications. Provision of these parts to the wider community through service/tools companies involved in supplying modules for synthetic biology/metabolic engineering will be an early translational outcome of our work and this will benefit service/tools companies working in this space. Our Pathways to Impact document indicates routes to early commercialisation of Parts that will emerge from this study.

More broadly, the availability of new component Parts for the engineering of biology will benefit industries operating in the bioeconomy. Such Parts will facilitate metabolic engineering programmes where light (rather than expensive chemicals) can be used to control flux through metabolic pathways, or the controlled expression of target products (e.g. therapeutic proteins, enzymes, antibodies) without relying on the use of expensive chemicals to induce expression of introduced genes. An optogenetic approach also opens up the possibility of real-time monitoring of production during fermentation/processing, which will provide major benefits to those companies involved in the bioproduction of chemicals, materials and biologics from engineered biological hosts. This will create improved, lower cost manufacturing processes for a wide range of products, increasing on the longer term the capacity of UK manufacturing industries operating in this space.

The research will lead to highly trained personnel with skills in a variety of time-resolved spectroscopic and macromolecular structural characterisation methods, and also with complementary skills in computation and synthetic biology. Highly trained staff and educational materials based on time-resolved structural techniques will emerge from the proposed work, allowing the UK to fully exploit the exciting new era of XFEL radiation. This will be invaluable to the entire UK structural biology community in the future in terms of developing the expertise necessary, in conjunction with the UK XFEL hub, to maximise UK XFEL based research output. All members of the team will gain experience of working in an integrated and interdisciplinary manner which will be important in developing relevant skils for future employment within interdisciplinary environments, e.g. in building new capacity for the bioeconomy. Team members will also become effective at communication and dissemination. Wider interaction with the MIB interdisciplinary science and outreach community will enable cross-discipline working, co-development of science with other experts in allied disciplines and wider honing of skills to complement core scientific/communication activities. Interaction with SMEs and industry colleagues as part of the Pathways to Impact activities (e.g. translation/basic discovery science workshops) will also develop translational skills and awareness of the commercial world.

Societal benefits will accumulate on the longer term. By enabling the development of new manufacturing platforms through optogenetic control our work will underpin new manufacturing capabilities e.g. in the bioeconomy (currently estimated at £1.7 Tn in the EU). This will have longer term impact on the establishment of green biomanufacturing processes, especially for chemicals, materials and biopharmaceuticals, which are major growth areas for the UK bioeconomy (in 2015 contributing £36 billion directly to the UK economy and supporting over 600 thousand jobs).