PURIFICATION, SPECTROSCOPIC ANALYSIS AND BIOLOGICAL-ACTIVITY OF THE MACROCYCLIC DIHYDROXAMATE SIDEROPHORE ALCALIGIN PRODUCED BY BORDETELLA-PERTUSSIS AND BORDETELLA-BRONCHISEPTICA

Hydroxamate siderophores of virulent Bordetella pertussis and Bordetel la bronchiseptica strains were purified using a simple large-scale iso lation procedure, and identified by various spectroscopic techniques a s the macrocyclic dihydroxamate siderophore trivially known as alcalig in, 1,6,11,16-tetraazacycloeicosane-2,5,12,15-tetrone, which was previ ously isolated from the taxonomically-related bacterial species Alcali genes denitrificans subsp, xylosoxydans. Alcaligin purified from iron- depleted cultures of B. pertussis and B. buonchiseptica exhibited spec ific growth-promoting activity under iron-restricted conditions for Bo rdetella indicator strains, and were active in [Fe-55]ferric alcaligin transport assays. Evidence suggests that several C-2-symmetric confor mations of alcaligin exist simultaneously in both methanolic and aqueo us solution.