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Zhang H, Sun T, Cao X, Wang Y, Ma Z, Wang Y, Yang N, Xu M, Deng X, Li H, Wang B, Yi J, Wang Z, Zhang Q, Chen C. Scanning iron response regulator binding sites using Dap-seq in the Brucella genome. PLoS Negl Trop Dis 2023; 17:e0011481. [PMID: 37459300 PMCID: PMC10374146 DOI: 10.1371/journal.pntd.0011481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 07/27/2023] [Accepted: 06/26/2023] [Indexed: 07/28/2023] Open
Abstract
Iron is an essential element required for all organisms. Iron response regulator (Irr) is a crucial transcriptional regulator and can affect the growth and iron uptake of Brucella. The growth rate of Brucella melitensis M5-90 irr mutant was significantly lower than that of B. melitensis M5-90 under normal or iron-sufficient conditions, however, the growth rate of the B. melitensis M5-90 irr mutant was significantly higher than that of B. melitensis M5-90 under iron-limited conditions. In addition, irr mutation significantly reduced iron uptake under iron-limited conditions. Previous studies suggested that the Irr protein has multiple target genes in the Brucella genome that are involved in iron metabolism. Therefore, in the present study, a Dap-seq approach was used to investigate the other iron metabolism genes that are also regulated by the Irr protein in Brucella. A total of seven genes were identified as target genes for Irr in this study and the expression levels of these seven genes was identified using qRT-PCR. The electrophoretic mobility shift assay confirmed that six out of the seven genes, namely rirA (BME_RS13665), membrane protein (BME_RS01725), hypothetical protein (BME_RS09560), ftrA (BME_RS14525), cation-transporting P-type ATPase (zntA) (BME_RS10660), and 2Fe-2S binding protein (BME_RS13655), interact with the Irr protein. Furthermore, the iron utilization and growth assay experiments confirmed that rirA was involve in iron metabolism and growth of Brucella. In summary, our results identified six genes regulated by the Irr protein that may participate in iron metabolism, and the rirA was identified as a regulon of Irr and it also plays a role in iron metabolism of Brucella. Collectively, these results provide valuable insights for the exploration of Brucella iron metabolism.
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Affiliation(s)
- Huan Zhang
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Tianhao Sun
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Xudong Cao
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
- School of Medicine, HeXi University, Zhangye City, Gansu, China
| | - Yifan Wang
- State key Laboratory of Agricultural Microbiology/College of Veterinary Medicine Huazhong Agricultural University 1 Wuhan, China
| | - Zhongchen Ma
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Yueli Wang
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Ningning Yang
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Mingguo Xu
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Xiaoyu Deng
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Honghuan Li
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Benben Wang
- School of Life Science, Shihezi University, Shihezi City, Xinjiang, China
| | - Jihai Yi
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Zhen Wang
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
| | - Qian Zhang
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
- State Key Laboratory for Sheep Genetic Improvement and Healthy Production, Xinjiang Academy of Agriculture and Reclamation Science,Shihezi, Xinjiang, China
| | - Chuangfu Chen
- School of Animal Science and Technology, Shihezi University, Shihezi City, Xinjiang, China
- Collaborative Innovation Center for Prevention and Control of High Incidence Zoonotic Infectious Diseases in Western China, Shihezi, Xinjiang, China
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Roop RM, Barton IS, Hopersberger D, Martin DW. Uncovering the Hidden Credentials of Brucella Virulence. Microbiol Mol Biol Rev 2021; 85:e00021-19. [PMID: 33568459 PMCID: PMC8549849 DOI: 10.1128/mmbr.00021-19] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Bacteria in the genus Brucella are important human and veterinary pathogens. The abortion and infertility they cause in food animals produce economic hardships in areas where the disease has not been controlled, and human brucellosis is one of the world's most common zoonoses. Brucella strains have also been isolated from wildlife, but we know much less about the pathobiology and epidemiology of these infections than we do about brucellosis in domestic animals. The brucellae maintain predominantly an intracellular lifestyle in their mammalian hosts, and their ability to subvert the host immune response and survive and replicate in macrophages and placental trophoblasts underlies their success as pathogens. We are just beginning to understand how these bacteria evolved from a progenitor alphaproteobacterium with an environmental niche and diverged to become highly host-adapted and host-specific pathogens. Two important virulence determinants played critical roles in this evolution: (i) a type IV secretion system that secretes effector molecules into the host cell cytoplasm that direct the intracellular trafficking of the brucellae and modulate host immune responses and (ii) a lipopolysaccharide moiety which poorly stimulates host inflammatory responses. This review highlights what we presently know about how these and other virulence determinants contribute to Brucella pathogenesis. Gaining a better understanding of how the brucellae produce disease will provide us with information that can be used to design better strategies for preventing brucellosis in animals and for preventing and treating this disease in humans.
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Affiliation(s)
- R Martin Roop
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Ian S Barton
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Dariel Hopersberger
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Daniel W Martin
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
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3
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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 2019; 32:273-291. [PMID: 30810877 DOI: 10.1007/s10534-019-00184-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 02/18/2019] [Indexed: 11/28/2022]
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.
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Affiliation(s)
- Vanesa Amarelle
- Instituto de Investigaciones Biologicas Clemente Estable, Montevideo, Uruguay
| | - Uriel Koziol
- Instituto de Investigaciones Biologicas Clemente Estable, Montevideo, Uruguay
| | - Elena Fabiano
- Instituto de Investigaciones Biologicas Clemente Estable, Montevideo, Uruguay.
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4
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Pokorzynski ND, Thompson CC, Carabeo RA. Ironing Out the Unconventional Mechanisms of Iron Acquisition and Gene Regulation in Chlamydia. Front Cell Infect Microbiol 2017; 7:394. [PMID: 28951853 PMCID: PMC5599777 DOI: 10.3389/fcimb.2017.00394] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 08/23/2017] [Indexed: 01/19/2023] Open
Abstract
The obligate intracellular pathogen Chlamydia trachomatis, along with its close species relatives, is known to be strictly dependent upon the availability of iron. Deprivation of iron in vitro induces an aberrant morphological phenotype termed "persistence." This persistent phenotype develops in response to various immunological and nutritional insults and may contribute to the development of sub-acute Chlamydia-associated chronic diseases in susceptible populations. Given the importance of iron to Chlamydia, relatively little is understood about its acquisition and its role in gene regulation in comparison to other iron-dependent bacteria. Analysis of the genome sequences of a variety of chlamydial species hinted at the involvement of unconventional mechanisms, being that Chlamydia lack many conventional systems of iron homeostasis that are highly conserved in other bacteria. Herein we detail past and current research regarding chlamydial iron biology in an attempt to provide context to the rapid progress of the field in recent years. We aim to highlight recent discoveries and innovations that illuminate the strategies involved in chlamydial iron homeostasis, including the vesicular mode of acquiring iron from the intracellular environment, and the identification of a putative iron-dependent transcriptional regulator that is synthesized as a fusion with a ABC-type transporter subunit. These recent findings, along with the noted absence of iron-related homologs, indicate that Chlamydia have evolved atypical approaches to the problem of iron homeostasis, reinvigorating research into the iron biology of this pathogen.
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Affiliation(s)
- Nick D Pokorzynski
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State UniversityPullman, WA, United States
| | - Christopher C Thompson
- Jefferiss Trust Laboratories, Faculty of Medicine, Imperial College London, St. Mary's HospitalLondon, United Kingdom
| | - Rey A Carabeo
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State UniversityPullman, WA, United States
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Wang Q, Wang X, Zhang W, Li X, Zhou Y, Li D, Wang Y, Tian J, Jiang W, Zhang Z, Peng Y, Wang L, Li Y, Li J. Physiological characteristics of Magnetospirillum gryphiswaldense MSR-1 that control cell growth under high-iron and low-oxygen conditions. Sci Rep 2017; 7:2800. [PMID: 28584275 PMCID: PMC5459824 DOI: 10.1038/s41598-017-03012-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 04/21/2017] [Indexed: 11/17/2022] Open
Abstract
Magnetosome formation by Magnetospirillum gryphiswaldense MSR-1 is dependent on iron and oxygen levels. We used transcriptome to evaluate transcriptional profiles of magnetic and non-magnetic MSR-1 cells cultured under high-iron and low-iron conditions. A total of 80 differentially expressed genes (DEGs) were identified, including 53 upregulated and 27 downregulated under high-iron condition. These DEGs belonged to the functional categories of biological regulation, oxidation-reduction process, and ion binding and transport, and were involved in sulfur metabolism and cysteine/methionine metabolism. Comparison with our previous results from transcriptome data under oxygen-controlled conditions indicated that transcription of mam or mms was not regulated by oxygen or iron signals. 17 common DEGs in iron- and oxygen-transcriptomes were involved in energy production, iron transport, and iron metabolism. Some unknown-function DEGs participate in iron transport and metabolism, and some are potential biomarkers for identification of Magnetospirillum strains. IrrA and IrrB regulate iron transport in response to low-oxygen and high-iron signals, respectively. Six transcription factors were predicted to regulate DEGs. Fur and Crp particularly co-regulate DEGs in response to changes in iron or oxygen levels, in a proposed joint regulatory network of DEGs. Our findings provide new insights into biomineralization processes under high- vs. low-iron conditions in magnetotactic bacteria.
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Affiliation(s)
- Qing Wang
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China.,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China
| | - Xu Wang
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China.,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China
| | - Weijia Zhang
- Institute of Deep-sea Science and Engineering, China Academy of Sciences, Sanya, 572000, P.R. China.,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China
| | - Xianyu Li
- Beijing Key Laboratory of Traditional Chinese Medicine Basic Research on Prevention and Treatment for Major Diseases, Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, 100700, P.R. China
| | - Yuan Zhou
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China
| | - Dan Li
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China
| | - Yinjia Wang
- Tianjin Biochip Corporation, Tianjin, 300457, P.R. China
| | - Jiesheng Tian
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China.,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China
| | - Wei Jiang
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China.,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China
| | - Ziding Zhang
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China
| | - Youliang Peng
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China
| | - Lei Wang
- Tianjin Biochip Corporation, Tianjin, 300457, P.R. China
| | - Ying Li
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China. .,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China.
| | - Jilun Li
- State Key Laboratories for Agro-biotechnology, China Agricultural University, Beijing, 100193, P.R. China.,France-China Bio-mineralization and Nano-structure Laboratory, Beijing, 100193, P.R. China
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6
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Dailey HA, Dailey TA, Gerdes S, Jahn D, Jahn M, O'Brian MR, Warren MJ. Prokaryotic Heme Biosynthesis: Multiple Pathways to a Common Essential Product. Microbiol Mol Biol Rev 2017; 81:e00048-16. [PMID: 28123057 PMCID: PMC5312243 DOI: 10.1128/mmbr.00048-16] [Citation(s) in RCA: 191] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The advent of heme during evolution allowed organisms possessing this compound to safely and efficiently carry out a variety of chemical reactions that otherwise were difficult or impossible. While it was long assumed that a single heme biosynthetic pathway existed in nature, over the past decade, it has become clear that there are three distinct pathways among prokaryotes, although all three pathways utilize a common initial core of three enzymes to produce the intermediate uroporphyrinogen III. The most ancient pathway and the only one found in the Archaea converts siroheme to protoheme via an oxygen-independent four-enzyme-step process. Bacteria utilize the initial core pathway but then add one additional common step to produce coproporphyrinogen III. Following this step, Gram-positive organisms oxidize coproporphyrinogen III to coproporphyrin III, insert iron to make coproheme, and finally decarboxylate coproheme to protoheme, whereas Gram-negative bacteria first decarboxylate coproporphyrinogen III to protoporphyrinogen IX and then oxidize this to protoporphyrin IX prior to metal insertion to make protoheme. In order to adapt to oxygen-deficient conditions, two steps in the bacterial pathways have multiple forms to accommodate oxidative reactions in an anaerobic environment. The regulation of these pathways reflects the diversity of bacterial metabolism. This diversity, along with the late recognition that three pathways exist, has significantly slowed advances in this field such that no single organism's heme synthesis pathway regulation is currently completely characterized.
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Affiliation(s)
- Harry A Dailey
- Department of Microbiology, Department of Biochemistry and Molecular Biology, and Biomedical and Health Sciences Institute, University of Georgia, Athens, Georgia, USA
| | - Tamara A Dailey
- Department of Microbiology, Department of Biochemistry and Molecular Biology, and Biomedical and Health Sciences Institute, University of Georgia, Athens, Georgia, USA
| | - Svetlana Gerdes
- Fellowship for Interpretation of Genomes, Burr Ridge, Illinois, USA
| | - Dieter Jahn
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universitaet Braunschweig, Braunschweig, Germany
| | - Martina Jahn
- Institute of Microbiology, Technische Universitaet Braunschweig, Braunschweig, Germany
| | - Mark R O'Brian
- Department of Biochemistry, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Martin J Warren
- Department of Biosciences, University of Kent, Canterbury, Kent, United Kingdom
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7
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Hohle TH, O'Brian MR. Metal-specific control of gene expression mediated by Bradyrhizobium japonicum Mur and Escherichia coli Fur is determined by the cellular context. Mol Microbiol 2016; 101:152-66. [PMID: 26998998 DOI: 10.1111/mmi.13381] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2016] [Indexed: 01/21/2023]
Abstract
Bradyrhizobium japonicum Mur and Escherichia coli Fur are manganese- and iron-responsive transcriptional regulators, respectively, that belong to the same protein family. Here, we show that neither Mur nor Fur discriminate between Fe(2+) and Mn(2+) in vitro nor is there a metal preference for conferral of DNA-binding activity on the purified proteins. When expressed in E. coli, B. japonicum Mur responded to iron, but not manganese, as determined by in vivo promoter occupancy and transcriptional repression activity. Moreover, E. coli Fur activity was manganese-dependent in B. japonicum. Total and chelatable iron levels were higher in E. coli than in B. japonicum under identical growth conditions, and Mur responded to iron in a B. japonicum iron export mutant that accumulated high levels of the metal. However, elevated manganese content in E. coli did not confer activity on Fur or Mur, suggesting a regulatory pool of manganese in B. japonicum that is absent in E. coli. We conclude that the metal selectivity of Mur and Fur depends on the cellular context in which they function, not on intrinsic properties of the proteins. Also, the novel iron sensing mechanism found in the rhizobia may be an evolutionary adaptation to the cellular manganese status.
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Affiliation(s)
- Thomas H Hohle
- Department of Biochemistry, State University of New York at Buffalo, Buffalo, NY, 14214, USA
| | - Mark R O'Brian
- Department of Biochemistry, State University of New York at Buffalo, Buffalo, NY, 14214, USA
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8
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HmuS and HmuQ of Ensifer/Sinorhizobium meliloti degrade heme in vitro and participate in heme metabolism in vivo. Biometals 2016; 29:333-47. [DOI: 10.1007/s10534-016-9919-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 12/20/2022]
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9
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Abstract
Iron is an essential nutrient, but it can also be toxic. Therefore, iron homeostasis must be strictly regulated. Transcriptional control of iron-dependent gene expression in the rhizobia and other taxa of the Alphaproteobacteria is fundamentally different from the Fur paradigm in Escherichia coli and other model systems. Rather than sense iron directly, the rhizobia employ the iron response regulator (Irr) to monitor and respond to the status of an iron-dependent process, namely, heme biosynthesis. This novel control mechanism allows iron homeostasis to be integrated with other cellular processes, and it permits differential control of iron regulon genes in a manner not readily achieved by Fur. Moreover, studies of Irr have defined a role for heme in conditional protein stability that has been subsequently described in eukaryotes. Finally, Irr-mediated control of iron metabolism may reflect a cellular strategy that accommodates a greater reliance on manganese.
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Affiliation(s)
- Mark R O'Brian
- Department of Biochemistry, State University of New York at Buffalo, New York 14214;
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10
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Nagy TA, Moreland SM, Detweiler CS. Salmonella acquires ferrous iron from haemophagocytic macrophages. Mol Microbiol 2014; 93:1314-26. [PMID: 25081030 DOI: 10.1111/mmi.12739] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2014] [Indexed: 01/21/2023]
Abstract
Bacteria harbour both ferrous and ferric iron transporters. We now report that infection of macrophages and mice with a Salmonella enterica Typhimurium strain containing an inactivated feoB-encoded ferrous iron transporter results in increased bacterial replication, compared to infection with wild type. Inactivation of other cation transporters, SitABCD or MntH, did not increase bacterial replication. The feoB mutant strain does not have an intrinsically faster growth rate. Instead, increased replication correlated with increased expression in macrophages of the fepB-encoded bacterial ferric iron transporter and also required siderophores, which capture ferric iron. Co-infection of mice with wild type and a feoB mutant strain yielded a different outcome: FeoB is clearly required for tissue colonization. In co-infected primary mouse macrophages, FeoB is required for S. Typhimurium replication if the macrophages were IFNγ treated and contain phagocytosed erythrocytes, a model for haemophagocytosis. Haemophagocytes are macrophages that have engulfed erythrocytes and/or leucocytes and can harbour Salmonella in mice. These observations suggest that Salmonella acquires ferrous iron from haemophagocytic macrophages.
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Affiliation(s)
- Toni A Nagy
- Department of Molecular, Cellular and Developmental Biology, University of Colorado-Boulder, Boulder, CO, USA
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11
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Elhassanny AEM, Anderson ES, Menscher EA, Roop RM. The ferrous iron transporter FtrABCD is required for the virulence ofBrucella abortus2308 in mice. Mol Microbiol 2013; 88:1070-82. [DOI: 10.1111/mmi.12242] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Ahmed E. M. Elhassanny
- Department of Microbiology and Immunology; East Carolina University School of Medicine; Greenville; NC; 27834; USA
| | - Eric S. Anderson
- Department of Biology; East Carolina University School of Medicine; Greenville; NC; 27858; USA
| | - Evan A. Menscher
- Department of Microbiology and Immunology; East Carolina University School of Medicine; Greenville; NC; 27834; USA
| | - R. Martin Roop
- Department of Microbiology and Immunology; East Carolina University School of Medicine; Greenville; NC; 27834; USA
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12
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Tavares AFN, Nobre LS, Saraiva LM. A role for reactive oxygen species in the antibacterial properties of carbon monoxide-releasing molecules. FEMS Microbiol Lett 2012; 336:1-10. [PMID: 22774863 DOI: 10.1111/j.1574-6968.2012.02633.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 07/02/2012] [Accepted: 07/03/2012] [Indexed: 12/24/2022] Open
Abstract
Carbon monoxide-releasing molecules (CO-RMs) are, in general, transition metal carbonyl complexes that liberate controlled amounts of CO. In animal models, CO-RMs have been shown to reduce myocardial ischaemia, inflammation and vascular dysfunction, and to provide a protective effect in organ transplantation. Moreover, CO-RMs are bactericides that kill both Gram-positive and Gram-negative bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. Herein are reviewed the microbial genetic and biochemical responses associated with CO-RM-mediated cell death. Particular emphasis is given to the data revealing that CO-RMs induce the generation of reactive oxygen species (ROS), which contribute to the antibacterial activity of these compounds.
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Affiliation(s)
- Ana Filipa N Tavares
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
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