Notably, xenobiotics derived from microbial toxins are currently being explored for their use in cancer treatment . Therefore, the identification of microorganisms producing toxins and the detection of toxins in complex matrices (environmental samples or body fluids) is of importance for the One Health concept. Recently established databases condensing information about microbial toxins and antitoxins, like Toxinome , or tools for the prediction of toxin genes from (meta-) genomic data, like PathoFact , will facilitate the in-depth exploration of these microbial effectors. Metaproteomics was used to identify metabolic changes in the gut microbiome in response to toxins and could help in the optimization of microbiome degradation capability for soil remediation purposes. Additionally, meta-(proteomics) can be used to verify the expression of protein toxins, or proteins involved in the biosynthesis and regulation of toxins .