November 13, 2019
University of Sheffield
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.
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.
Story Source:
Materials provided by University of Sheffield. Note:
Content may be edited for style and length.
Related Multimedia:
Journal Reference:
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. Cryo-EM
structure of the spinach cytochrome b6 f complex at 3.6 Å resolution. Nature,
2019; DOI: 10.1038/s41586-019-1746-6
No comments:
Post a Comment