Characterization of Fluorescent and Nonfluorescent Peptide Siderophores Produced by Pseudomonas syringae Strains and Their Potential Use in Strain Identification

• DOI: 10.1128/aem.67.4.1718-1727.2001
• Publication Date: 2002-07-27T10:00:58Z
• Authors: Alain Bultreys; Isabelle Gheysen; Henri Maraite; Edmond de Hoffmann
• Keywords: Pyoverdine; Pseudomonas syringae; Chromophore

ABSTRACT Nonfluorescent highly virulent strains of Pseudomonas syringae pv. aptata isolated in different European countries and Uruguay produce a nonfluorescent peptide siderophore, the production which is iron repressed specific to these strains. The amino acid composition this siderophore identical that dominant fluorescent produced by P. strains, molecular masses respective Fe(III) chelates are 1,177 1,175 atomic mass units. unchelated converted into at pH 10, colors spectral characteristics siderophores Fe(III)-chelates acidic conditions similar those dihydropyoverdins pyoverdins, respectively. used These results additional spectrometry data strongly suggest presence pyoverdin chromophore dihydropyoverdin both ligated succinamide residue. When chelated, behave differently from typical pyoverdins neutral alkaline conditions, apparently because ionization occurring around 4.5 carboxylic acids present β-hydroxyaspartic residues chains. differences can be detected visually pH-dependent changes chelate spectrophotochemically. electrophoretic behavior chelated offer new tools discriminate between saprophytic species viridiflava distinguish two siderovars aptata.