(co-supervising with Michael Lalk, Greifswald University (Germany))
Today, there are many pathogens that are resistance against common antibiotics. This so-called antimicrobial resistance crisis is a serious and global issue. In my PhD project I analyse the chemical ecology of social spiders (genus Stegodyphus) collected in Namibia to find a novel antibiotic. There live numerous microorganisms in, on, and around the spiders and their nests. We hypothesized that the microorganisms produce bioactive compounds to protect the spiders against pathogens. Finding and identification of these compounds could be an important step in the engagement against the antimicrobial resistance crisis.
We use two approaches for the research for novel antibiotics: One the one hand, we look for non-volatile compounds. To find these compounds we isolate and cultivate microorganisms from the spider’s microbiome. The next step is to bring these microorganisms in contact with common pathogens for humans (ESKAPE pathogens) to induce and show the antimicrobial effect (e.g. using agar diffusion test) followed by the extraction of possible bioactive compounds. The subsequent analysis is performed by liquid chromatography-mass spectrometry (LC-MS).
On the other hand, we designed different experiments for the identification of volatile compounds: We trap the volatiles in spider’s nests as well as from isolated spiders and microorganisms using different adsorbent materials. The subsequent analysis is performed by gas chromatography-mass spectrometry (GC-MS).