Credit: University of Sheffield
- Scientists reveal ‘beating heart’ of photosynthesis that is responsible for significantly influencing plant growth.
- Study shows how an electrical reaction in protein complex cytochrome b6f provides the energy that plants need to turn carbon dioxide into the carbohydrates and biomass that sustain the global food chain.
- Discovery could allow experts to redesign future photosynthesis in crop plants to achieve higher yields and meet urgent food security needs for a growing global population.
Scientists have solved the structure of one of the key components of photosynthesis, a discovery that could lead to photosynthesis being ‘redesigned’ to achieve higher yields and meet urgent food security needs.
The study, led by the University of Sheffield and published today in the journal Nature, reveals the structure of cytochrome b6f – the protein complex that significantly influences plant growth via photosynthesis.
Photosynthesis is the foundation of life on Earth providing the food, oxygen and energy that sustains the biosphere and human civilisation.
Using a high-resolution structural model, the team found that the protein complex provides the electrical connection between the two light-powered chlorophyll-proteins (Photosystems I and II) found in the plant cell chloroplast that convert sunlight into chemical energy.
Lorna Malone, the first author of the study and a PhD student in the University of Sheffield’s Department of Molecular Biology and Biotechnology, said: “Our study provides important new insights into how cytochrome b6f utilises the electrical current passing through it to power up a ‘proton battery’. This stored energy can then be then used to make ATP, the energy currency of living cells. Ultimately this reaction provides the energy that plants need to turn carbon dioxide into the carbohydrates and biomass that sustain the global food chain.”
The high-resolution structural model, determined using single-particle cryo-electron microscopy, reveals new details of the additional role of cytochrome b6f as a sensor to tune photosynthetic efficiency in response to ever-changing environmental conditions. This response mechanism protects the plant from damage during exposure to harsh conditions such as drought or excess light.
Dr Matt Johnson, reader in Biochemistry at the University of Sheffield and one of the supervisors of the study added: “Cytochrome b6f is the beating heart of photosynthesis which plays a crucial role in regulating photosynthetic efficiency.
“Previous studies have shown that by manipulating the levels of this complex we can grow bigger and better plants. With the new insights we have obtained from our structure we can hope to rationally redesign photosynthesis in crop plants to achieve the higher yields we urgently need to sustain a projected global population of 9-10 billion by 2050”.
The research was conducted in collaboration with the Astbury Centre for Structural Molecular Biology at the University of Leeds.
Researchers now aim to establish how cytochrome b6f is controlled by a myriad of regulatory proteins and how these regulators affect the function of this complex.
For further information please contact: Shemina Davis, Media Relations Manager, University of Sheffield, 0114 222 5339 or sh[email protected]
Notes to editors
The University of Sheffield
With almost 29,000 of the brightest students from over 140 countries, learning alongside over 1,200 of the best academics from across the globe, the University of Sheffield is one of the world’s leading universities.
A member of the UK’s prestigious Russell Group of leading research-led institutions, Sheffield offers world-class teaching and research excellence across a wide range of disciplines.
Unified by the power of discovery and understanding, staff and students at the university are committed to finding new ways to transform the world we live in.
Sheffield is the only university to feature in The Sunday Times 100 Best Not-For-Profit Organisations to Work For 2018 and for the last eight years has been ranked in the top five UK universities for Student Satisfaction by Times Higher Education.
Sheffield has six Nobel Prize winners among former staff and students and its alumni go on to hold positions of great responsibility and influence all over the world, making significant contributions in their chosen fields.
Global research partners and clients include Boeing, Rolls-Royce, Unilever, AstraZeneca, Glaxo SmithKline, Siemens and Airbus, as well as many UK and overseas government agencies and charitable foundations.