Within the framework of our effort to discover new bioactive metabolites from Gram-negative bacteria, trinickiabactin (1) was isolated from the plant pathogenic strain Trinickia caryophylli DSM 50341. Whole genome sequencing allowed the identification of its biosynthetic gene cluster. The structure of 1 bears a rare diazeniumdiolate ligand system and was elucidated by a combination of NMR- and MS-spectroscopic techniques and bioinformatics. Trinickiabactin was found to be antibacterial toward several Gram-negative bacteria (MIC values ranged from 3.5 to 34.0 µg ml