The Microbiology Group's research is focused on Gram-positive bacteria and comprises stress tolerance and response, the maturation process of heme-proteins, cell differentiation and division, and the characterization of oxidoreductases. The studies are mainly focused on the model organisms Bacillus subtilis and Streptomyces coelicolor. However, they also involve other prokaryotic organisms, for example the enteric bacterium Enterococcus faecalis.
Heme-containing proteins are essential to most cells. Examples of such proteins are hemoglobin, cytochromes, and catalase. Intracellular transport of heme and assembly of heme-proteins are poorly understood processes that are addressed in three projects; Heme A biogenesis, Cytochrome c biogenesis, and Assembly of catalase. Bacterial endospores are probably the most endurable forms of life known, for example they resist heat, chemicals, desiccation and radiation. The heat-resistance is dependent on the cortex layer of the endospore. One line of research concerns regulation of cortex synthesis by a thiol-disulfide redox switch in a penicillin-binding protein.
How is it possible to build a three-dimensional cell based on the information contained in the genes? This is a task all organisms face. The cytoskeleton, a network of dynamic protein filaments, is an important tool to structurally organize the cells both in eukaryotes and prokaryotes. One type of cytoskeleton is built of proteins with coiled coil structure. In animal cells these proteins are called intermediate filaments (IF). Over 30 human diseases have been linked to mutations in genes encoding IF proteins. We and others have shown that an analogous cytoskeleton is also present in bacteria, making them attractive as tractable model organisms to study IF-like cytoskeletons.
Growth and proliferation of the bacterial cell depends on processes that are highly organised in space and time. For example, proteins involved in cell division, cell wall synthesis, or segregation of chromosomes are directed to be active only at specific sites in the cell. The bacterial cytoskeleton (which shares much similarity with the eukaryotic cytoskeleton) is crucial for this level of organisation and the targeting and movement of proteins and DNA within the cell, but other mechanisms contribute as well. We are investigating how fundamental processes like cell wall growth, cell polarity, cell division, and morphological differentiation are organised and regulated in a large group of Gram-positive bacteria called the Actinobacteria. They are of large medical and industrial relevance and include both antibiotic-producing Streptomyces and pathogens like Mycobacterium tuberculosis.
Under hostile or challenging environmental conditions, for example depletion of nutrients, oxygen, and changes in temperature, bacteria launch stress responses which improve their chances to adapt to and to survive various insults. In addition, a variety of chemical threats also provoke a stress response. The research within the Microbiology Group on bacterial stress responses will further the understanding of the basic survival mechanisms of some the most adaptable organisms on the planet.