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The molecular mechanisms of the bacterial iron sensor IdeR

Life came to depend on iron as a cofactor for many essential enzymatic reactions. However, once the atmosphere was oxygenated, iron became both scarce and toxic. Therefore, complex mechanisms have evolved to scavenge iron from an environment in which it is poorly bioavailable, and to tightly regulat...

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Autores principales: Marcos-Torres, Francisco Javier, Juniar, Linda, Griese, Julia J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Portland Press Ltd. 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10317159/
https://www.ncbi.nlm.nih.gov/pubmed/37140254
http://dx.doi.org/10.1042/BST20221539
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author Marcos-Torres, Francisco Javier
Juniar, Linda
Griese, Julia J.
author_facet Marcos-Torres, Francisco Javier
Juniar, Linda
Griese, Julia J.
author_sort Marcos-Torres, Francisco Javier
collection PubMed
description Life came to depend on iron as a cofactor for many essential enzymatic reactions. However, once the atmosphere was oxygenated, iron became both scarce and toxic. Therefore, complex mechanisms have evolved to scavenge iron from an environment in which it is poorly bioavailable, and to tightly regulate intracellular iron contents. In bacteria, this is typically accomplished with the help of one key regulator, an iron-sensing transcription factor. While Gram-negative bacteria and Gram-positive species with low guanine-cytosine (GC) content generally use Fur (ferric uptake regulator) proteins to regulate iron homeostasis, Gram-positive species with high GC content use the functional homolog IdeR (iron-dependent regulator). IdeR controls the expression of iron acquisition and storage genes, repressing the former, and activating the latter in an iron-dependent manner. In bacterial pathogens such as Corynebacterium diphtheriae and Mycobacterium tuberculosis, IdeR is also involved in virulence, whereas in non-pathogenic species such as Streptomyces, it regulates secondary metabolism as well. Although in recent years the focus of research on IdeR has shifted towards drug development, there is much left to learn about the molecular mechanisms of IdeR. Here, we summarize our current understanding of how this important bacterial transcriptional regulator represses and activates transcription, how it is allosterically activated by iron binding, and how it recognizes its DNA target sites, highlighting the open questions that remain to be addressed.
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spelling pubmed-103171592023-07-04 The molecular mechanisms of the bacterial iron sensor IdeR Marcos-Torres, Francisco Javier Juniar, Linda Griese, Julia J. Biochem Soc Trans Review Articles Life came to depend on iron as a cofactor for many essential enzymatic reactions. However, once the atmosphere was oxygenated, iron became both scarce and toxic. Therefore, complex mechanisms have evolved to scavenge iron from an environment in which it is poorly bioavailable, and to tightly regulate intracellular iron contents. In bacteria, this is typically accomplished with the help of one key regulator, an iron-sensing transcription factor. While Gram-negative bacteria and Gram-positive species with low guanine-cytosine (GC) content generally use Fur (ferric uptake regulator) proteins to regulate iron homeostasis, Gram-positive species with high GC content use the functional homolog IdeR (iron-dependent regulator). IdeR controls the expression of iron acquisition and storage genes, repressing the former, and activating the latter in an iron-dependent manner. In bacterial pathogens such as Corynebacterium diphtheriae and Mycobacterium tuberculosis, IdeR is also involved in virulence, whereas in non-pathogenic species such as Streptomyces, it regulates secondary metabolism as well. Although in recent years the focus of research on IdeR has shifted towards drug development, there is much left to learn about the molecular mechanisms of IdeR. Here, we summarize our current understanding of how this important bacterial transcriptional regulator represses and activates transcription, how it is allosterically activated by iron binding, and how it recognizes its DNA target sites, highlighting the open questions that remain to be addressed. Portland Press Ltd. 2023-06-28 2023-05-04 /pmc/articles/PMC10317159/ /pubmed/37140254 http://dx.doi.org/10.1042/BST20221539 Text en © 2023 The Author(s) https://creativecommons.org/licenses/by/4.0/This is an open access article published by Portland Press Limited on behalf of the Biochemical Society and distributed under the Creative Commons Attribution License 4.0 (CC BY) (https://creativecommons.org/licenses/by/4.0/) . Open access for this article was enabled by the participation of Uppsala University in an all-inclusive Read & Publish agreement with Portland Press and the Biochemical Society under a transformative agreement with Bibsam.
spellingShingle Review Articles
Marcos-Torres, Francisco Javier
Juniar, Linda
Griese, Julia J.
The molecular mechanisms of the bacterial iron sensor IdeR
title The molecular mechanisms of the bacterial iron sensor IdeR
title_full The molecular mechanisms of the bacterial iron sensor IdeR
title_fullStr The molecular mechanisms of the bacterial iron sensor IdeR
title_full_unstemmed The molecular mechanisms of the bacterial iron sensor IdeR
title_short The molecular mechanisms of the bacterial iron sensor IdeR
title_sort molecular mechanisms of the bacterial iron sensor ider
topic Review Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10317159/
https://www.ncbi.nlm.nih.gov/pubmed/37140254
http://dx.doi.org/10.1042/BST20221539
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