Genome Mining Guided Identification of the Metallophore Delftichelin A from <i>Delftia deserti</i>

A targeted sequencing and genome mining approach for delftibactin-like biosynthetic pathways revealed three distinct biosynthetic gene cluster architectures (BGC <i>del</i>, <i>dlc</i> and <i>dlp</i>) encoded in genomes of members of the genus <i>Delftia</i>. Comparative metabolomic analysis guided the isolation and characterization of a yet unreported metallophore, delftichelin A from <i>Delftia deserti</i> DSM1621 (previously named <i>Delftia acidovorans</i> DSM1621). Prediction of BGC architecture and A domain specificity was in line with the structure analysis uncovering previously unreported differences in amino acid composition and modifications. Analysis of bioactivity and metal-binding characteristics demonstrated that delftichelin A shows a preferential affinity for ferric iron, while also exhibiting heavy metal detoxification mechanisms via oxidative degradation, analogous to those reported for the delftibactin family of compounds.