Welcome to the research group “Mechanisms of Molecular Machines”

Prof. Dr. Dagmar Klostermeier

Our lab investigates the role of ATP-driven conformational changes for the catalytic activity of helicases and topoisomerases using single-molecule FRET experiments. Helicases and topoisomerases are energy-coupling enzymes that convert the energy of ATP hydrolysis into structural changes in their substrates. RNA helicases mediate a multitude of RNA rearrangements in transcription, RNA splicing and editing, RNA export, mRNA translation, ribosome assembly, RNA degradation, and potentially RNA folding in general. In accordance with their variety of functions, they are associated with complex processes such as ageing, differentiation, and cancer. Topoisomerases change the topological state of DNA in an ATP-dependent reaction. DNA topology impacts key cellular events such as replication, transcription, recombination, and the storage of the genome as chromatin. Furthermore, cooperation between helicases and topoisomerases is required to maintain genome integrity.

To comprehensively understand the mechanisms of these enzymes and the regulation of their activities, we employ a wide variety of techniques, including molecular biology, protein and nucleic acid biochemical techniques, FPLC and HPLC chromatography, absorption, fluorescence and circular dichroism spectroscopy, steady-state and pre-steady-state kinetics, calorimetric methods, and time-resolved single-molecule fluorescence spectroscopy by confocal and total internal reflection microscopy.