Cell envelope related processes in Bacillus subtilis
Bacteria are separated from the environment by a cell envelope, which forms the barrier between the inside and outside of the cell. The cell envelope of the Gram-positive bacterium Bacillus subtilis is composed of a membrane (lipid bilayer) and a cell wall that provides rigidity to the cell and prevents cell lysis. The cell envelope is a dynamic structure that constantly adapts to its environment.
In this thesis, several processes that occur within the cell envelope have been studied. Firstly, the function of a membrane protein that was assumed to play a role in the regulation of cell death has been characterized. Instead of regulating cell death, this protein appeared to function in efficient pyruvate utilization. Moreover, our research focused on the consequences of deleting wall teichoic acids from the cell wall. Previous research showed that wall teichoic acids are not essential, but our research revealed the occurrence of secondary mutations in these mutants, thereby questioning their essentiality. Finally, environmental effects on the cell envelope have been studied, and the effects of cold shock and interaction with a fungus on gene transcription of Bacillus subtilis have been identified. Overall, this thesis increases our knowledge on different component of the cell envelope of Bacillus subtilis and their specific functioning.