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Iron utilization studies in Citrobacter species.

S Khashe·J M Janda
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Abstract

Seventy-one strains of Citrobacter were screened for iron scavenging mechanisms by biologic and chemical assays. Essentially all citrobacteria (70/71) were found to elaborate enterobactin-like siderophores by both biologic and chemical assays, however only c. koseri (C. diversus) was found to produce aerobactin. The concentration of ethylenediamine di(o-hydroxyphenylacetic acid) (EDDA) required to inhibit the growth of individual Citrobacter strains by depleting free iron ranged from 250 micrograms/ml to 100 micrograms/ml. Iron utilization studies of selected citrobacter isolates indicated that hemin and hematin could reverse the effects of iron limitation on growth under iron-stressed conditions (1000 micrograms/ml of EDDA). Two C. koseri strains grown under iron-restricted conditions showed similar changes in their whole cell protein profiles including induction of high molecular mass proteins (72-83 kDa) which may play a role in iron acquisition under iron-stressed conditions. The collective results support an additional virulence-associated mechanism for C. koseri strains which may help explain the greater pathogenic potential this group has for causing serious extraintestinal disease in humans.

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Bacterial ProteinsChelating AgentsCitrobacterEdetic AcidEnterobacteriaceae InfectionsEnterobactinHumansHydroxamic AcidsIronMolecular WeightSiderophoresVirulenceJournal Article

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BibTeXRIS

S Khashe, J M Janda. 1996-04-01. Iron utilization studies in Citrobacter species.. https://doi.org/10.1111/j.1574-6968.1996.tb08096.x

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