Let op! Cell wall under construction

The shape of the bacterial cell is determined by a cell wall composed of peptidoglycan (PG). PG synthesis involves the synthesis of its building block (Lipid II) in the cytoplasm, which is flipped over the membrane and incorporated into the cell wall by the Penicillin Binding Proteins (PBPs). The study of cell wall synthesis helps to understand the increased bacterial resistance to current antibiotics, and to develop new antibiotics. In this thesis, three lines of research are worked out, using the Gram-positive rod-shaped organism Bacillus subtilis as a model.

The first research line explored the mode of action of nisin, a lantibiotic with a pore-forming capacity, which also clusters Lipid II in the membrane. Our data showed that both processes are linked. The second line studied chemical differences in cell wall composition. We showed that the composition of the division septum differs from the lateral wall, as it is enriched in material that is not yet processed or crosslinked. Finally, the function of the PBP2B PASTA domains was analysed. We showed that although the PASTA domains are not required for PBP2B localization, they do play a role in cell division, most likely by interacting with the cell division protein DivIB.

Dissertation: http://hdl.handle.net/11370/5cf7eef9-b3d7-4ed6-9de4-a8f259dc3f24