Our genome is constantly copied, modified, rearranged and maintained. We are interested in how the complex machineries are functioning that drive these biological processes. To this end we develop new biophysical tools that allow to monitor the activity as well as conformational states of single biomolecular machines in real time. This includes so-called tweezers techniques where magnetic and photonic forces are used to probe the mechanical properties and the states of single biomolecules. We combine such measurements with singe-molecule fluorescence approaches that report on the localization and on nanoscopic conformational changes of individual molecular players. Our single-molecule measurements are complemented by physical modeling in order to understand the main working principles of biomolecular machines.
Using this methodology we investigate the physical processes that lead to DNA compaction in the nucleus of cells, decipher the mechanisms of motor enzymes that are involved in the repair of broken DNA and explore how CRISPR-Cas enzymes that currently revolutionize the field of genome engineering are recognizing their programmable targets.

Beyond understanding biomolecular machines we also try to make use of biological principles in order to fabricate artificial bioinspired nanosystems. Hereby we exploit DNA as building material to fabricate three-dimensional objects of complex shape and with designed functionality. These structures are applied in membrane biophysics as well as for the self-assembly of nanoelectronic components.

Prof. Ralf Seidel 
Peter Debye Institute for Soft Matter Physics 
Universität Leipzig


  • Welcome Iman, our new Postdoc 🙂
  • Sadly we had to bid our farewell to Dominik after nearly 15 wonderful years in our group.
    We wish him all the best at his new position!
  • Congrats to both Dominik and Patrick for their succesfull PhD defense.
    And both succeded with Summa cum laude!!!


Molecular Biophysics group
Universität Leipzig
Peter Debye Institute for Soft Matter Physics
Linnéstr. 5
04103 Leipzig
Tel. +49 341 97 32550


The Faculty of Physics and Earth Sciences can be reached from Leipzig main station by public transport using tram no. 16 (direction Lößnig, exit Johannisallee) and from Leipzig airport by local train S5 or S5X (exit Bayerischer Bahnhof).

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