Ball-and-stick representations of the metal complexes from the crystal structures of (A) yersiniabactin-Fe(III) (CCDC ID: 619878)31 and (B) micacocidin-Zn(II) (micacocidin A, CCDC ID: 130920).76 Non-polar hydrogen atoms have been omitted for clarity. Colour code: C gray, O red, N blue, H white, Fe orange, and Zn green.