Pyoverdin, Ferribactin, Azotobactin -a New Triade of Siderophores from Pseudomonas chlororaphis ATCC 9446 and Its Relation to Pseudomonas fluorescens ATCC 13525

It is shown that Pseudomonas fluorescens ATCC 13525 and Pseudomonas chlororaphis ATCC 9446 produce identical pyoverdins and ferribactins. As the structures of these sidero­ phores are usually species or even strain specific this exception should be kept in mind in view of the reclassification of the genus Pseudomonas. From Pseudomonas chlororaphis an additional siderophore could be obtained which has the same peptide chain as the co-occur­ ring pyoverdins and ferribactin, but a chromophore which is typical for azotobactins from Azotobacter vinelandii.