[Expired] PhD: Physico-chemical characterization of long wavelength photosynthesis

With Prof A Rutherford and Dr M Roessler, at Imperial College, London, UK.

Project Description

It has often been suggested that crops and micro-algae might be made more efficient by engineering them to use longer wavelength pigments. Recently our group showed that nature had already done the engineering: oxygenic photosynthesis does occur using lower energy, near-infra-red light. This occurs in some cyanobacteria when they find themselves shaded from visible light but still irradiated by the infra-red.1 In this project we seek to understand how this newly found type of photosynthesis works.

This requires detailed chemical characterization (thermodynamics, kinetics, electrostatics, structure-function) of the photo-enzymes to determine what differences exist compared to the usual chlorophyll-a-containing system that dominates the biosphere. Thermodynamic information will come from a) kinetics (forward- and back-reaction rates give equilibrium constants and thus redox energy gaps) and b) measurement of the reduction potentials of redox cofactors to provide absolute values.2,4. Structure/function information will come from i) spectroscopy (including UV-vis-IR and EPR)1,3,7; iii) cryoEM and crystallography; iv) evolutionary approaches5 , and v) computational approaches6. Most methods will require isolation and purification of the photosystems as well as molecular genetic approaches. The student will have the opportunity to use these physical, chemical and biochemical approaches in the labs of the supervisors and their collaborators abroad. This interdisciplinary project will provide a knowledge base for the eventual design of engineering projects aimed at moving the long-wavelength photosynthesis trait into other species that are potentially agriculturally and biotechnologically relevant.

We are looking to recruit an outstanding Masters level graduate in Chemistry, Biochemistry, Biophysics or an equivalent subject, with a strong interest in developing and applying novel (bio)chemical and spectroscopic tools to address specific aspects of this project. The PhD studentship is fully funded for 3.5 years. The successful candidate will receive training in a range of spectroscopic methods including advanced EPR spectroscopy, electrochemistry, protein purification and structural determination, molecular enzymology. The student will be encouraged to design, construct and/or customize the spectroscopic and electrochemical set-ups as required to solve the specific biological problems. The student will be based in Life Sciences in the South Kensington Campus but is expected to interact closely with the Chemistry team at Imperial’s White City campus.

Residential & Academic Eligibility

UK or EU nationals who are ordinarily residents of the UK are eligible to apply. Candidates must carefully read Annex 1 of the RCUK Training Grant Guide (https://www.ukri.org/files/legacy/publications/rcuk-training-grant-guide-pdf/) to determine their own eligibility before applying. Candidates are expected to have a BSc degree, in a relevant subject, at 2:1 level or better, as well as a postgraduate Masters qualification, by October 2020. Although preference will be given to Masters level candidates, exceptional students at Bachelor’s level may also be considered.

How to Apply

Please visit our BBSRC DTP webpage to obtain more information on how to apply (https://www.imperial.ac.uk/bbsrc-doctoral-training-partnership/)
Deadline for applications: 12noon on Friday, 24 April 2020.

Funding Notes

The studentships cover: (i) an annual tax-free stipend at the standard Research Council rate (£17,009 for 2019-2020, to be confirmed for 2020-2021 but typically increases annually in line with inflation), (ii) contribution towards research costs, and (iii) tuition fees at the UK/EU rate.
Studentships will last for 3.5 years full-time.


1 Nürnberg D.J., Morton J., Santabarbara S., Telfer A., Joliot P., Antonaru L.A., Ruban A.V., Cardona T., Krausz E., Boussac A., Fantuzzi A, Rutherford A.W. (2018) Science 360, 1210- 1213 Photochemistry beyond the red limit in chlorophyll f–containing photosystems DOI: 10.1126/aar8313
2 De Causmaecker, S., Douglass, J.S.; Fantuzzi, A. and Rutherford A.W. 2019 Proc.Natl Acad Sci USA. 116, 19458-19463 Energetics of the exchangeable quinone, QB, in Photosystem II
3 Le Breton N., Wright JJ., Jones AJY, Salvadori E, Bridges HR Hirst J, Roessler MM (2017), Journal of the American Chemical Society 139 (45), 16319-16326 Using Hyperfine Electron Paramagnetic Resonance Spectroscopy to Define the Proton-Coupled Electron Transfer Reaction at Fe–S Cluster N2 in Respiratory Complex I
4 Abdiaziz, E Salvadori, KP Sokol, E Reisner, MM Roessler (2019), Chemical Communications 55 (60), 8840-8843, Protein film electrochemical EPR spectroscopy as a technique to investigate redox reactions in biomolecules
5 Cardona T and Rutherford A.W. (2019) Trends in Plant Science 24, 1008-1021 Evolution of Photochemical reaction centres: more twists
6. Ugur I., Rutherford A.W. Kaila V.R.I. (2016) Biochim. Biophys. Acta 1857, 740-748 Redox-coupled substrate water reorganization in the active site of Photosystem II: the role of calcium in substrate water delivery
7. Roessler M and Salvadori E (2018) Chem. Soc. Rev., 47, 2534-2553 Principles and applications of EPR spectroscopy in the chemical sciences