USE OF SIDEROPHORES TO TYPE PSEUDOMONADS - THE 3 PSEUDOMONAS-AERUGINOSA PYOVERDINE SYSTEMS

Eighty-eight Pseudomonas aeruginosa isolates, most of them from the Co llection of Bacterial Strains of the Institut Pasteur, Paris, were ana lysed for their pyoverdine-mediated iron incorporation system by diffe rent methods, including pyoverdine isoelectrofocusing analysis, pyover dine-mediated growth stimulation, immunoblot detection of (ferri)pyove rdine outer-membrane receptor and pyoverdine-facilitated iron uptake. The same grouping of the strains was reached by each of these methods, resulting in the classification of the P. aeruginosa isolates, even t hose which were devoid of pyoverdine production, into three different siderophore types. Forty-two percent of the strains were identified wi th the type-strain P. aeruginosa ATCC 15692 (group I), 42% were identi cal with the second type-strain P. aeruginosa ATCC 27853 (group II) an d 16% reacted identically with the clinical isolate P. aeruginosa Pa6, whose pyoverdine was recognized in this study to be identical in stru cture to the pyoverdine produced by a natural isolate, P. aeruginosa s train R. No new pyoverdine species was detected among these strains.