Experts Unlock Key to Photosynthesis

Written by University of Sheffield on November 21, 2019. Posted in Current News

Scientists revealed the ‘beating heart’ of photosynthesis that is responsible for significantly influencing plant growth.

A new 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.

The 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 (Wednesday 13 November 2019) 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 overall process of photosynthesis

Credit: At09kg / Wikimedia Commons

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 using their cryo-electron microscope facilities.

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.
Contacts and sources:
University of Sheffield
Citation: Cryo-EM structure of the spinach cytochrome b6 f complex at 3.6 Å resolution. Lorna A. Malone, Pu Qian, Guy E. Mayneord, Andrew Hitchcock, David A. Farmer, Rebecca F. Thompson, David J. K. Swainsbury, Neil A. Ranson, C. Neil Hunter, Matthew P. Johnson. Nature, 2019; DOI: 10.1038/s41586-019-1746-6

Source: http://www.ineffableisland.com/2019/11/experts-unlock-key-to-photosynthesis.html

PRINCIPIA SCIENTIFIC INTERNATIONAL, legally registered in the UK as a company incorporated for charitable purposes. Head Office: 27 Old Gloucester Street, London WC1N 3AX.

Please DONATE TODAY To Help Our Non-Profit Mission To Defend The Scientific Method.

Trackback from your site.

Comments (5)

Chris

November 21, 2019 at 6:42 pm | #

This is not unlike solar power. Where two dissimilar doped plates are next to each other and the introduction of ultraviolet radiation does work on the loose electrons to carry them from one location to another.

Reply
- dave jr
  
  November 24, 2019 at 3:16 pm | #
  
  The way I read it, it is very much unlike solar power. With solar power, the dislodged electron is a one off event, over and done, adding to the panels’ degradation.
  
  Imagine a ‘living’ solar panel where cytochrome b6f and chloroplasts convert sunlight to electricity to be harvested directly, before the hydrocarbon formation and with little degradation.
  
  Reply
geran

November 21, 2019 at 6:58 pm | #

An “ordinary” tree is more complex than a car factory. It can make its own food, grow, reproduce, and heal itself. All instructions are in its DNA and passed on to the next generation.

From photosynthesis, it makes a variety of hydrocarbon cells, and then transports them to where they are needed–new roots, new leaves, new bark, or seeds.

And we still don’t understand how it does it all!

Reply
Andy Rowlands

November 21, 2019 at 10:39 pm | #

Very interesting, if this study does prove what they hope, and with the increasing CO2 stimulating better growth as well, the combination should enable even higher yields than we already have.

Reply
HerbbRose

November 22, 2019 at 1:08 am | #

It worries me when people studying a system they don’t understand perceive a “problem”and try to fix it. Perhaps photorespiration is how a plant exhales.
Should we begin putting more CO2 into the air to provide the the food that theses plants will need to grow faster?

Reply