Journalartikel

Jahr der Veröffentlichung: 2015

Seiten: 790-802

Zeitschrift: MicrobiologyOpen

Bandnummer: 4

Heftnummer: 5

ISSN: 2045-8827

Open Access Status: Gold

DOI Link: https://doi.org/10.1002/mbo3.279

Verlag: Wiley

Abstract: 
IscR proteins are known as transcriptional regulators for Fe-S biogenesis. In the facultatively phototrophic bacterium, Rhodobacter sphaeroides IscR is the product of the first gene in the isc-suf operon. A major role of IscR in R. sphaeroides iron-dependent regulation was suggested in a bioinformatic study (Rodionov etal., PLoS Comput Biol 2:e163, 2006), which predicted a binding site in the upstream regions of several iron uptake genes, named Iron-Rhodo-box. Most known IscR proteins have Fe-S clusters featuring (Cys)(3)(His)(1) ligation. However, IscR proteins from Rhodobacteraceae harbor only a single-Cys residue and it was considered unlikely that they can ligate an Fe-S cluster. In this study, the role of R. sphaeroides IscR as transcriptional regulator and sensor of the Fe-S cluster status of the cell was analyzed. A mutant lacking IscR is more impaired in growth under iron limitation than the wild-type and exhibits significantly increased ROS levels in iron-replete and iron-deplete conditions. Expression studies reveal that R. sphaeroides IscR in its cluster-bound form functions as transcriptional repressor of genes involved in iron metabolism by direct binding to the promoter region of genes preceded by the motif. A total of 110 genes are directly or indirectly affected by IscR. Furthermore, IscR possesses a unique Fe-S cluster ligation scheme with only a single cysteine involved.

Harvard-Zitierstil: Remes, B., Eisenhardt, B., Srinivasan, V. and Klug, G. (2015) IscR of Rhodobacter sphaeroides functions as repressor of genes for iron-sulfur metabolism and represents a new type of iron-sulfur-binding protein, MicrobiologyOpen, 4(5), pp. 790-802. https://doi.org/10.1002/mbo3.279

APA-Zitierstil: Remes, B., Eisenhardt, B., Srinivasan, V., & Klug, G. (2015). IscR of Rhodobacter sphaeroides functions as repressor of genes for iron-sulfur metabolism and represents a new type of iron-sulfur-binding protein. MicrobiologyOpen. 4(5), 790-802. https://doi.org/10.1002/mbo3.279