Skip to main content
Log in

Highly conserved nucleotide motifs present in the 5′UTR of the heme-receptor gene shmR are required for HmuP-dependent expression of shmR in Ensifer meliloti

  • Published:
BioMetals Aims and scope Submit manuscript

Abstract

Heme may represent a major iron-source for bacteria. In the symbiotic nitrogen-fixing bacterium Ensifer meliloti 1021, iron acquisition from heme depends on the outer-membrane heme-receptor ShmR. Expression of shmR gene is repressed by iron in a RirA dependent manner while under iron-limitation its expression requires the small protein HmuP. In this work, we identified highly conserved nucleotide motifs present upstream the shmR gene. These motifs are widely distributed among Alpha and Beta Proteobacteria, and correlate with the presence of HmuP coding sequences in bacterial genomes. According to data presented in this work, we named these new motifs as HmuP-responsive elements (HPREs). In the analyzed genomes, the HPREs were always present upstream of genes encoding putative heme-receptors. Moreover, in those Alpha and Beta Proteobacteria where transcriptional start sites for shmR homologs are known, HPREs were located in the 5′UTR region. In this work we show that in E. meliloti 1021, HPREs are involved in HmuP-dependent shmR expression. Moreover, we show that changes in sequence composition of the HPREs correlate with changes in a predicted RNA secondary structure element and affect shmR gene expression.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

References

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Elena Fabiano.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOC 50 kb)

Supplementary material 2 (DOC 215 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Amarelle, V., Koziol, U. & Fabiano, E. Highly conserved nucleotide motifs present in the 5′UTR of the heme-receptor gene shmR are required for HmuP-dependent expression of shmR in Ensifer meliloti. Biometals 32, 273–291 (2019). https://doi.org/10.1007/s10534-019-00184-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10534-019-00184-6

Keywords

Navigation