Research award winner presents results at Paderborn University's Research Day
Antibiotic-resistant germs are responsible for nine per cent of all deaths worldwide - and the trend is rising. This means that they are increasingly posing major problems for medical professionals. This is where a research project by Dr Adrian Keller, head of the "Nanobiomaterials" group in the Department of Chemistry at Paderborn University, comes in. His aim is to modify existing antibiotics using DNA nanostructures in order to restore the effectiveness of drugs against resistance. Two years ago, Keller was honoured with the Paderborn University Research Prize for his work. He has now presented his results at the Day of Research.
Architecture with the genetic material
Keller uses a special method known as "DNA origami". This involves folding DNA strands into arbitrary three-dimensional structures - these can be triangles, squares or even more complex structures - on which active substances can be precisely arranged. To this end, the scientists couple the molecules of the antibiotic vancomycin and other molecular components to the DNA strands from which the nanostructures are built. Vancomycin has been used against MRSA infections since the 1980s. However, there are also pathogens that are multi-resistant to this antibiotic. "With the help of DNA origami, we can design novel drug delivery systems," explains the research award winner. The result: in the tests, the modified nanostructures bound to the cell wall of the bacteria as desired, damaging the structure of the cell wall. This means that the onset of a growth-inhibiting effect is theoretically possible. However, there are still hurdles.
"We have discovered that the antimicrobial effect is strongly influenced by the size of the nanostructures used. Even if our designed structures bind to the target molecules, their size prevents them from penetrating deep enough into the cell wall to significantly inhibit bacterial growth. We want to investigate this important role of structure size in more detail in future experiments," says Keller. In the experiments, he also discovered that some bacterial species can decompose the DNA nanostructures and use them as nutrients. "Both aspects must - and can - be taken into account when designing DNA nanostructures for future antimicrobial applications."
Cooperation with other European partners
In future, all areas of application in which DNA nanostructures come into contact with bacteria will benefit from the research results, from medicine to biotechnology. "We are currently expanding our method to other antimicrobial molecules that interact with the cell membrane instead of the cell wall," says Keller, who is already sharing his knowledge with other European partner organisations from science and industry such as the Austrian Institute of Technology (AIT), TU Dresden and the Fraunhofer Institute for Cell Therapy and Immunology (IZI) in Leipzig. Cooperation partners in Tartu, Estonia, are also using the vancomycin-DNA conjugates to specifically bind lipid particles filled with antibiotics to bacteria.
This text has been translated automatically.
