The primary research focus of scientists working in the Microbial Proteomics Research Group is on the human pathogens Staphylococcus aureus and Pseudomonas aeruginosa. These bacteria are among the most feared human pathogens worldwide that are responsible for more than half of all hospital infections. Particularly alarming in this context is the growing number of infections with multi-resistant strains that do not respond to treatment with conventional antibiotics and thus frequently lead to death of a patient.
This is why it is important that new treatment strategies for these pathogens have to be developed that can readily be implemented in the clinical setting. To this end, an in-depth knowledge of these pathogens´ pathophysiology and virulence is urgently warranted – which is the reason why our scientists are specifically looking at identifying the link between the pathogens´ physiology and its knack for colonizing its host and causing disease.
The true effectors inside a cell are proteins. As these proteins are key to the bacterium's interaction with its host, HZI scientists are not only interested in a systematic investigation of protein synthesis and degradation in bacterial cells, but they are also trying to shed light on these molecules' activity and modifications and on the jobs they perform. In particular, they focus on very small proteins with up to 100 amino acids that are still rarely characterized.
In order to document and study the total of bacterial proteins under pre-specified conditions and at specific points in time within a closed system, our scientists are drawing on a range of different research tools based on mass spectrometry. Using appropriate methods of preparation, proteins are assigned to specific cellular compartments and quantified.
This way, cytoplasmic proteins can be easily distinguished from membrane and surface bound or even secretory proteins. Any change in terms of quantity or type of modification can be analyzed.
Our researchers use these tools to study the regulation and function of bacterial proteins involved in host adaptation for identifying potential new virulence determinants and their targets in the host. They are looking at how S. aureus and P. aeruginosa adapt to situations of stress and starvation and to exposure to antibiotics and which proteins are essential for these processes. Another research focus is on development of new methods and algorithms for predicting and identifying small proteins in bacteria.