Dr. Nicole Ludwig receives the MarBiNa Award 2021
Max Planck junior scientist is recognized for her work on a fungal pathogen
In view of the steadily growing world population, fungal pathogens on grain are a severe problem. In her doctoral thesis, Max Planck junior scientist Nicole Ludwig investigated the highly complex interaction between a fungal pathogen and its host plant. Her findings open up new possibilities for controlling plant diseases. In recognition of her work, Lord Mayor Dr. Thomas Spies awarded her the Marburg Biotechnology and Nanotechnology Promotion Prize 2021.
The fungus Ustilago maydis, which causes corn smut disease, represents a large group of fungal pathogens that destroy large quantities of grain crops worldwide. Many of these fungi are biotrophic, that is, they do not kill their host plant. Instead, they prevent the plant from dying and thrive at its expense to ensure their own growth and propagation.
For this purpose, Ustilago maydis manipulates the corn plant by releasing a broad arsenal of so-called effector molecules into the plant tissue. Nicole Ludwig was able to isolate a fungal complex of seven proteins that is apparently indispensable for its invasion.
"If even a single one of these proteins is missing, the infection process stops completely. Because of its pivotal role, the effector complex would be an ideal target to combat the disease," says Nicole Ludwig. Nicole Ludwig's work was carried out in the research team led by Prof. Regine Kahmann at the Max Planck Institute for Terrestrial Microbiology in Marburg. Regine Kahmann dedicated many years to understanding the interaction between U. maydis and the corn plant at the molecular level.
The fungus probably uses the complex, which also includes two proteins located in the membrane, to introduce further effectors into plant cells. "With this protein complex and our evidence that it forms a structure, we have for the first time discovered a fungal machinery that could be used to introduce effectors into the host cell. This is a great result of fundamental research. Simultaneously, it has enormous application potential," says Regine Kahmann. However, the biotrophic lifestyle of the fungus presents a challenge. "The complex only forms in the context of successful fungal infection. If you inhibit its formation, the fungus dies upon entering the plant. Therefore, it has not yet been possible to directly prove that the complex is responsible for the introduction of effectors into the plant cell," explains Nicole Ludwig.
However, the researchers are optimistic that their discovery will open up new approaches. The search for active substances with novel modes of action is of utmost importance here, because the risk of developing resistance is very high, just as it is with antibiotics.
Using a system developed by Nicole Ludwig, the team, in collaboration with the Compound Management and Screening Center (COMAS) at the MPI for Molecular Physiology in Dortmund, Germany, found several candidate drug classes, three of which not only inhibited the smut fungus U. maydis, but also symptoms of the rust fungus Uromyces fabae. This gives hope that these compounds will also be effective against related pathogens of economically important diseases, such as Asian soybean rust or wheat rust.
Because the protein complex appears to be unique to certain plant pathogenic fungi - comparable proteins were not found in any of the host plants or in other organisms - the risk of harmful ecological effects - in contrast to classical plant protection agents - would be rather low.
"Nicole Ludwig has not only contributed significantly to the characterization of the complex, but has also advanced the aspect of application of this knowledge. This has allowed us to find new molecules for the control of fungal diseases on plants and to submit them for patenting," says Regine Kahmann. At present, the work, especially on the structural elucidation of the complex, is being continued in the research lab of Max Planck Fellow and Marburg University Professor Gert Bange.
The Initiative for Bio- and Nanotechnology e.V., (IBiNa) was founded in 2007. IBiNa promotes young scientists in the field of biotechnology and nanotechnology and awards them for their outstanding work.
More about the award at https://initiative-biotechnologie.de/marbina/