Molecular Structure Annotation

Every day, our bodies encounter millions of foreign chemical compounds. Among the most dangerous are reactive electrophilic species—unstable molecules that can bind to DNA and proteins, potentially leading to chronic diseases. Fortunately, our bodies fight back using glutathione conjugation, excreting these toxins as urinary mercapturic acid conjugates (MACs). But until now, checking urine to see exactly what toxins we’ve been exposed to was incredibly difficult because standard tracking methods miss highly unstable chemical structures. Researchers developed an analytical strategy that dramatically expands our ability to profile the urinary “adductome”. By pairing high-resolution mass spectrometry with customized database construction and automated computational annotation using SIRIUS, this workflow uncovers hundreds of previously untraceable biomarkers.