Structure and Biosynthesis of Fimsbactins A–F, Siderophores from Acinetobacter baumannii and Acinetobacter baylyi

Abstract

<jats:title>Abstract</jats:title><jats:p>Novel chatechol/hydroxamate siderophores (named “fimsbactins”) were identified in <jats:italic>Acinetobacter baumannii</jats:italic> ATCC 17978 and <jats:italic>Acinetobacter baylyi</jats:italic> ADP1. The major compound, fimsbactin A, was isolated from low‐iron cultures of <jats:italic>A. baylyi</jats:italic> ADP1, and its chemical structure was elucidated by mass spectrometry, and detailed <jats:sup>1</jats:sup>H, <jats:sup>13</jats:sup>C and <jats:sup>15</jats:sup>N NMR spectroscopy. From inverse feeding experiments following HPLC‐MS analysis, the structures of five additional derivatives were elucidated. The gene cluster encoding the fimsbactin synthetase (<jats:italic>fbs</jats:italic>) was identified in both genomes, and mutants in <jats:italic>fbs</jats:italic> genes in <jats:italic>A. baylyi</jats:italic> were analyzed, thus allowing prediction of the fimsbactin biosynthesis pathway.