Infectious diseases have successfully been treated with antibiotics over the last century. Unfortunately, a significant threat of our time is antibiotic resistance, which is the ability of a microorganism to resist antibiotic treatment for which they were initially sensitive to. The emergence of antibiotic-resistant bacteria represents a high risk to public health, killing millions of people worldwide. To address this issue, research in the Pletzer Lab focuses on fighting infectious diseases and tackling antimicrobial resistance using innovative and interdisciplinary approaches.  

Our lab seeks to …

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… understand how microbes cause disease

Our research focuses to understand how microorganisms cause disease and what mechanisms they employ to overcome environmental stress. Of particular interest are polymicrobial infections (two or more microbes occupying the same niche) and how multiple microbes can change the course of infection and treatment. To accomplish this, we investigate host-pathogen interactions in culture conditions and in the context of complex skin infections such as abscesses and wounds. Our research examines a variety of important nosocomial organisms including all of the so-called ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) as well as Escherichia coli, Propionibacterium acnes, and Streptococcus pyogenes. 

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… fight antimicrobial resistance

Antibiotics are arguably the most important and successful medicines. However, the frequent growth of bacteria as biofilms, which are bacterial communities that grow in a protective matrix, is of great concern. Biofilm-associated infections (for example found in the cystic fibrosis lung or in chronic infections) are particularly difficult to treat with conventional antibiotics since bacteria growing within biofilms can be up to 1000-fold more resistant to antibiotics. This type of resistance is termed adaptive resistance and has been proposed to play a major role in reducing the therapeutic effectiveness of antimicrobial compounds. Currently, there is no specific treatment for such infections. The biofilm lifestyle is also associated with chronic infections predominantly caused by multiple bacterial species occupying the same infection site. We are therefore interested in how polymicrobial biofilms form during disease and what makes them so recalcitrant towards antibiotic treatment.

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… develop novel antimicrobial strategies

We have developed a murine skin infection model that forms the basis for the development and investigation of novel therapeutics to address the global problem of antimicrobial resistance to improve health and treatment. We are interested in compounds that exhibit broad-spectrum activity towards bacterial biofilms and/or work by neutralizing bacterial infection strategies rather than just killing them. The lab also works on strategies to overcome bacterial resistance mechanisms by developing antibiotic-conjugates that increase the uptake efficiency of already approved drugs.