PMID:15549269

From EcoliWiki
Jump to navigation Jump to search
Citation

Grass, G, Otto, M, Fricke, B, Haney, CJ, Rensing, C, Nies, DH and Munkelt, D (2005) FieF (YiiP) from Escherichia coli mediates decreased cellular accumulation of iron and relieves iron stress. Arch. Microbiol. 183:9-18

Abstract

The Escherichia coli yiiP gene encodes an iron transporter, ferrous iron efflux (FieF), which belongs to the cation diffusion facilitator family (CDF). Transcription of fieF correlated with iron concentration; however, expression appeared to be independent of the ferrous iron uptake regulator Fur. Absence of FieF led to decreased growth of E. coli cells in complex growth medium but only if fur was additionally deleted. The presence of EDTA was partially able to relieve this growth deficiency. Expression of fieF in trans rendered the double deletion strain more tolerant to iron. Furthermore, E. coli cells exhibited reduced accumulation of (55)Fe when FieF was expressed in trans. FieF catalyzed active efflux of Zn(II) in antiport with protons energized by NADH via the transmembrane pH gradient in everted membrane vesicles. Using the iron-sensitive fluorescent indicator PhenGreen-SK encapsulated in proteoliposomes, transmembrane fluxes of iron cations were measured with purified and reconstituted FieF by fluorescence quenching. This suggests that FieF is an iron and zinc efflux system, which would be the first example of iron detoxification by efflux in any organism.

Links

PubMed Online version:10.1007/s00203-004-0739-4

Keywords

Bacterial Proteins/metabolism; Biological Transport, Active/genetics; Biological Transport, Active/physiology; Escherichia coli/genetics; Escherichia coli/metabolism; Escherichia coli Proteins/genetics; Escherichia coli Proteins/metabolism; Fluorescent Dyes/metabolism; Gene Deletion; Genetic Complementation Test; Hydrogen-Ion Concentration; Ion Transport/genetics; Iron/metabolism; Membrane Transport Proteins/genetics; Membrane Transport Proteins/metabolism; Organic Chemicals; Repressor Proteins/metabolism; Zinc/metabolism

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.