[Pyoverdins from Pseudomonas putida].

The structures of two pyoverdins (Pp1 and Pp2) and one dihydropyoverdin (dihydro-Pp2) from a strain of Pseudomonas putida have been elucidated by spectroscopic methods and degradation studies. The pyoverdins Pp1 and Pp2 consist of a chromophore which was identified as (1S)-5-amino-2,3-dihydro-8,9-dihydroxy-1 H-pyrimido[1,2-a]quinoline-1- carboxylic acid substituted at the amino group with a 3-carboxypropanoyl or a succinamoyl residue and at the carboxy group with the N-terminus of L-Ser-L-Thr-D-Ser-L-Orn-L-threo-(OH)Asp-[D-Glu + L-Dab]*-L-Ser-D-allo-Thr- L-c(OH)Orn. Dihydro-Pp2 differs from Pp2 only in the chromophore, which is saturated at carbons 5 and 6. All compounds contain a tetrahydropyrimidine moiety ([D-Gln + L-Dab]*) resulting from the condensation of 2,4-diaminobutyric acid and glutamine.