New insight into photosynthesis could help grow more resilient plants

Scientists now have a new model to help them understand how plants store energy in their thylakoid membrane. PULLMAN (Wash.) - Washington State University researchers have created a computer model that explains how plants store energy in their thylakoid membrane. This is a critical structure for photosynthesis. With laboratory experiments, the team confirmed that the mathematical model was correct. Their work was published in Nature Plants. Helmut Kirchhoff, a professor at WSU's Institute of Biological Chemistry who led the team that made this discovery, said "We provided an essential piece to the overall puzzle of phytometabolism." "If we incorporate our model into the larger picture, it might provide a path for how to make plants more adaptable to certain environments." Photosynthesis converts sunlight into usable energy. However, plants constantly alter where and how they store this energy depending on temperature, light, and other factors. Understanding how plants adjust could help us understand how we perform in the field, and allow us to develop plants that can withstand climate change. Kirchhoff's and his colleagues' discoveries could have wide implications and benefits over the years, as their model is integrated to other models to learn more about photosynthesis. Specialized thylakoid membranes are found in chloroplasts in leaf leaves and convert sunlight into energy. Kirchhoff stated that it functions as a battery. "In leaves, plants pump protons across the thylakoid membrane from one end to the other creating a gradient of negative and positive charges." He said that ion channels regulate the energy storage to control fluctuations in energy. This complex process may be key to feeding the hungry on a warming planet. Kirchhoff stated that photosynthesis is extremely powerful. Kirchhoff stated that photosynthesis can be too powerful if it isn't controlled. This can cause it to produce too much energy which can lead to dangerous molecules that can kill plants. Plants with improved photosynthetic control could be engineered to survive in warmer, sunnier conditions. Scientists used a variety lighting techniques to illuminate leaves and measure the effects on absorption and fluorescence. Kirchhoff stated that "we illuminate leaves with different light intensities in order to create excited states of pigments." Kirchhoff said, "The leaf then alters its absorption and fluorescence properties that are measured to tell us what's going on inside." ### Meng Li, Vaclav Sloboda, Hans-Henning Kunz, and Hans-Henning Kunz, all from WSU, as well as Geoffry Davis, and David Kramer, from Michigan State University, are co-authors. This work was supported mainly by a grant from the U.S. Department of Energy (DE-SC0017160).