» Articles » PMID: 19093075

Heme-dependent Metalloregulation by the Iron Response Regulator (Irr) Protein in Rhizobium and Other Alpha-proteobacteria

Overview
Journal Biometals
Specialty Biochemistry
Date 2008 Dec 19
PMID 19093075
Citations 24
Authors
Affiliations
Soon will be listed here.
Abstract

Perception and response to nutritional iron by bacteria is essential for viability, and for the ability to adapt to the environment. The iron response regulator (Irr) is part of a novel regulatory scheme employed by Rhizobium and other Alpha-Proteobacteria to control iron-dependent gene expression. Bradyrhizobium japonicum senses iron through the status of heme biosynthesis to regulate gene expression, thus it responds to an iron-dependent process rather than to iron directly. Irr mediates this response by interacting directly with ferrochelatase, the enzyme that catalyzes the final step in heme biosynthesis. Irr is expressed under iron limitation to both positively and negatively modulate gene expression, but degrades in response to direct binding to heme in iron-sufficient cells. Studies with Rhizobium reveal that the regulation of iron homeostasis in bacteria is more diverse than has been generally assumed.

Citing Articles

The divalent metal ion exporter IhpABC is required to maintain iron homeostasis under low to moderate environmental iron conditions in the bacterium Bradyrhizobium japonicum.

Zhang F, OBrian M Mol Microbiol. 2023; 121(1):85-97.

PMID: 38038163 PMC: 10841971. DOI: 10.1111/mmi.15198.


Unusual Relationship between Iron Deprivation and Organophosphate Hydrolase Expression.

Nandavaram A, Nandakumar A, Kashif G, Sagar A, Shailaja G, Ramesh A Appl Environ Microbiol. 2023; 89(5):e0190322.

PMID: 37074175 PMC: 10231211. DOI: 10.1128/aem.01903-22.


Signaling and Detoxification Strategies in Plant-Microbes Symbiosis under Heavy Metal Stress: A Mechanistic Understanding.

Liu Y, He G, He T, Saleem M Microorganisms. 2023; 11(1).

PMID: 36677361 PMC: 9865731. DOI: 10.3390/microorganisms11010069.


Genomes from Uncultivated Pelagiphages Reveal Multiple Phylogenetic Clades Exhibiting Extensive Auxiliary Metabolic Genes and Cross-Family Multigene Transfers.

Wittmers F, Needham D, Hehenberger E, Giovannoni S, Worden A mSystems. 2022; 7(5):e0152221.

PMID: 35972150 PMC: 9599517. DOI: 10.1128/msystems.01522-21.


Genetic Redundancy in Iron and Manganese Transport in the Metabolically Versatile Bacterium Rhodopseudomonas palustris TIE-1.

Singh R, Ranaivoarisoa T, Gupta D, Bai W, Bose A Appl Environ Microbiol. 2020; 86(16).

PMID: 32503905 PMC: 7414945. DOI: 10.1128/AEM.01057-20.


References
1.
Martinez M, Ugalde R, Almiron M . Irr regulates brucebactin and 2,3-dihydroxybenzoic acid biosynthesis, and is implicated in the oxidative stress resistance and intracellular survival of Brucella abortus. Microbiology (Reading). 2006; 152(Pt 9):2591-2598. DOI: 10.1099/mic.0.28782-0. View

2.
Ishikawa H, Kato M, Hori H, Ishimori K, Kirisako T, Tokunaga F . Involvement of heme regulatory motif in heme-mediated ubiquitination and degradation of IRP2. Mol Cell. 2005; 19(2):171-81. DOI: 10.1016/j.molcel.2005.05.027. View

3.
Pohl E, Holmes R, Hol W . Crystal structure of a cobalt-activated diphtheria toxin repressor-DNA complex reveals a metal-binding SH3-like domain. J Mol Biol. 1999; 292(3):653-67. DOI: 10.1006/jmbi.1999.3073. View

4.
Ritz D, Patel H, Doan B, Zheng M, Aslund F, Storz G . Thioredoxin 2 is involved in the oxidative stress response in Escherichia coli. J Biol Chem. 2000; 275(4):2505-12. DOI: 10.1074/jbc.275.4.2505. View

5.
Elgrably-Weiss M, Park S, Schlosser-Silverman E, Rosenshine I, Imlay J, Altuvia S . A Salmonella enterica serovar typhimurium hemA mutant is highly susceptible to oxidative DNA damage. J Bacteriol. 2002; 184(14):3774-84. PMC: 135181. DOI: 10.1128/JB.184.14.3774-3784.2002. View