The Johnson Lab has been awarded £178, 389 by the Leverhulme Trust to investigate the structure and function of the photosynthetic membrane in plants using atomic force microscopy.
The funded research project is focused on the role of membrane organisation in photosynthesis. The enzymatic fixation of carbon dioxide into carbohydrate in the chloroplast stroma requires energy in the form of ATP and reducing power in the form of NADPH, which are provided by photosynthetic electron transport in the photosynthetic membrane. The photosynthetic membrane resides in the plant chloroplast and houses several major pigment-protein complexes involved electron transport including photosystem II, cytochrome b6f, photosystem I and ATP synthase.
As with many biological membranes these complexes are not homogenously distributed but instead are organised into distinct sub-domains- the grana and stromal lamellae. The efficiency of photosynthesis depends upon the rate of excitation energy transfer, the diffusion of electron carriers and the effectiveness of regulatory and repair processes, which in turn depend upon the spatial organisation of the pigment-protein complexes within these membrane domains.
The fundamentals of photosynthetic membrane organisation, dynamics and compartmentalisation revealed by the propject are key to unlocking the success story of the plant. The lessons learned will provide new targets for the future manipulation of crop plants to improve photosynthetic yield to feed the growing global population and inspire a new generation of solar and carbon capture devices to provide sustainable energy for the future.