Research

Research group „Antibiotic Resistance Transfer”

Type IV secretion systems (T4SS) are multiprotein complexes dedicated to the intercellular transport of proteins or protein-DNA complexes. T4SS translocate DNA and protein substrates across the cell envelope generally by a mechanism requiring direct contact with a recipient cell. Conjugative plasmid transfer is performed by a T4SS that transports DNA substrates to recipient cells in a contact-dependent process. My research group works on different research lines with the goal to understand and reduce the dissemination of antibiotic resistance via conjugative T4SS.

Type IV Secretion in Gram-positive Bacteria

Elucidation of the molecular mechanisms of antibiotic resistance and virulence factor transfer via type IV secretion systems in Gram-positive pathogenic bacteria. As model pathogens we study Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus, as model plasmid the conjugative resistance plasmid pIP501. Protein key factors of the type IV secretion system (T4SS) process are studied with respect to enzymatic function, cellular localization and protein-protein interactions. A first mechanistic model of T4SS in Gram-positive pathogens has been developed.

Molecular Monitoring of Microbial Contaminations

Detection and monitoring of antibiotic resistance and transfer genes in the environment by molecular tools, such as PCR, quantitative real-time PCR and quantification of resistance transfer via fluorescence monitoring tools. Environmental samples of interest are contaminated surface waters and soils. Samples are derived from the largest sewage field in the world, the Mezquital Valley, Mexico and from anthropogenic German and Indian soils.

Decontamination Strategies: Biofilm Inhibitors

Molecular studies on bacterial pathogens derived from closed environments, such as the International Space Station (ISS) and the Research Station CONCORDIA in the Antarctica. The Gram-positive isolates (with focus on Staphylococcus and Enterococcus) are studied with respect to biofilm formation, presence of resistance genes and conjugative transfer capabilities. Recently developed biofilm inhibitors are tested for applicability under microgravity conditions. The health risk of people working and/or living in closed habitats with respect to infection by multi drug resistant pathogens is assessed.