SURVEY ON NEWLY CHARACTERIZED IRON UPTAKE SYSTEMS OF YERSINIA-ENTEROCOLITICA

Iron assimilation systems have been shown to be important for virulenc e in Yersinia enterocolitica. In principle, iron transport in Y. enter ocolitica is similarly organized as in Escherichia coli although some differences exist in the siderophores used. A TonB function was identi fied which in a tonB mutant was complemented by the E. coli tonB gene. Three outer membrane receptors for siderophores were cloned and seque nced: FoxA for ferrioxamine B and E, FcuA for ferrichrome and HemR for heme uptake. In addition, two receptors were identified by mutants: C ccA for catechol cephalosporins and FyuA for yersiniabactin, the sider ophore produced by virulent yersiniae. In addition, the FyuA protein i s assumed to be the pesticin receptor.