Jan Löwe

Many cellular processes depend on complex proteins that share characteristics with machines. Our aim is to understand molecular machines at the atomic level while answering important questions relating to the biology of cells.

Our main area of research is the bacterial cytoskeleton and its roles in bacterial morphogenesis and cell division. In the past, we have been involved in showing that prokaryotes contain both actin and tubulin-like proteins that polymerise into filaments similar to their counterparts in eukaryotes.

It is now clear that the filament systems can be divided into dynamic, cytomotive and non-dynamic, cytoskeletal. For example, cytomotive filaments of tubulin-like FtsZ are part of the cytokinetic ring around the septum during bacterial cell division. Actin-like cytoskeletal MreB filaments control bacterial cell shape. Bacteria and archaea also contain filament systems that are unrelated to actins and tubulin, and we investigate their roles in morphogenesis and cell division.

A second theme of the group is SMC complexes, both bacterial and eukaryotic, in the shape of condensins and cohesins. We are currently using cryo-EM in order to discover the precise molecular mechanisms employed by these important and ubiquitous facilitators of chromosome biology.

In order to understand these systems and their mechanisms, in vitro and in vivo, we investigate at the level of cells with fluorescence light microscopy and electron cryo-tomography, and at the level of molecules with X-ray crystallography and electron cryo-microscopy.