The Pyoverdins of Pseudomonas syringae and Pseudomonas cichorii

Abstract

Abstract The structure elucidation of the cyclic (lactonic) forms of the pyoverdins with a succinamide side chain originally produced by the closely related species Pseudomonas syringae and P. cichorii is reported. Mass spectrometry and nuclear magnetic resonance analyses as well as the determination of the configuration of the amino acids after degradation indicate that these two pyoverdins differ only by the replacement of the first in-chain serine by glycine. The pyoverdins of P. syringae and P. cichorii and the dihydropyoverdin of P. syringae can be used by both species as siderophores.