Infectious diseases are caused by viruses, bacteria or fungi. The course and prognosis of these diseases depend largely on how well the immune system can recognize and eliminate the pathogen. Although specific agents do exist for many infectious diseases, e.g. antibiotics, the increase in resistance against many of these agents has propelled infections to become again a global threat. Finally, infectious diseases can occur not only in humans, but also in animals and plants, which represents an additional socioeconomic burden.

The BioHealth research area "Infectious Diseases" primarily investigates the molecular mechanisms of host-pathogen communication and resistance mechanisms, while at the same time aiming for the discovery of new active agents against these pathogens. BioHealth research on bacterial pathogens focuses on bacteria of the human gastrointestinal tract and associated diseases. Important model organisms used are Vibrio cholerae (causative agent of the secretory diarrheal disease cholera), Klebsiella oxytoca (responsible for antibiotic-associated hemorrhagic diarrhea), pathogenic Escherichia coli (the trigger of intestinal and urinary tract infections) and Campylobacter ssp. (causative agent of inflammatory diarrheal disease). In addition, research is also being conducted on difficult-to-treat hospital pathogens of the "ESKAPE" panel. Research on fungal pathogens focuses on the identification of novel antifungal agents and their mechanistic characterization, mainly based on studies with Candida albicans and Candida glabrata.

• Adaptation strategies of bacteria to changing environmental conditions.    
• Defense mechanisms of bacterial pathogens against the human immune system.
• Mechanisms of antibiotic resistance.
• Transfer of resistance and virulence genes via bacterial conjugation.
• Communication and genetic exchange between bacteria.    
• Influence of the gut microbiome on health and disease.    
• Role of microbial effectors released in the gut to modulate human somatic cells or other gut bacteria (gut microbiome).
• Characterization of novel vaccine candidates.
• Screening of natural products for novel antifungal agents, including their in vivo preclinical validation as well as the clarification of their mode of action.
• Regulated cell death in pathogenic fungi.
• Inhibition of lipases from human pathogenic bacteria (e.g. M. tuberculosis).