ABSTRACT
This chapter focuses on the structural characteristics and the physicochemical properties of pyoverdins and pseudobactins. It explores the culture conditions and describes the latest improvements in the purification procedures of pyoverdins. Few or many pyoverdins can be isolated from fluorescent Pseudomonas supernatants depending on the strain investigated. Some of them are really biosynthesized by the bacteria, but can give rise to closely related pyoverdins as the pH of the medium increases during the culture. NMR is also a very powerful method used for the structure determination of pyoverdins. They all show a common part in the aromatic region, characteristic of their common fluorescent chromophore. When fluorescent Pseudomonas are cultivated in iron-deficient conditions, they excrete several yellow-green, water-soluble fluorescent compounds called pyoverdins. These substances are chromopeptides possessing a chromophore derived from 2,3-diamino-6,7-di-hydroxyquinoline bound to a peptidic moiety identical for all the pyoverdins occurring from a given strain and differing generally from strain to strain.
