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Calvanese M, D’Angelo C, Tutino ML, Lauro C. Whole-Cell Biosensor for Iron Monitoring as a Potential Tool for Safeguarding Biodiversity in Polar Marine Environments. Mar Drugs 2024; 22:299. [PMID: 39057408 PMCID: PMC11277574 DOI: 10.3390/md22070299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 06/05/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024] Open
Abstract
Iron is a key micronutrient essential for various essential biological processes. As a consequence, alteration in iron concentration in seawater can deeply influence marine biodiversity. In polar marine environments, where environmental conditions are characterized by low temperatures, the role of iron becomes particularly significant. While iron limitation can negatively influence primary production and nutrient cycling, excessive iron concentrations can lead to harmful algal blooms and oxygen depletion. Furthermore, the growth of certain phytoplankton species can be increased in high-iron-content environments, resulting in altered balance in the marine food web and reduced biodiversity. Although many chemical/physical methods are established for inorganic iron quantification, the determination of the bio-available iron in seawater samples is more suitably carried out using marine microorganisms as biosensors. Despite existing challenges, whole-cell biosensors offer other advantages, such as real-time detection, cost-effectiveness, and ease of manipulation, making them promising tools for monitoring environmental iron levels in polar marine ecosystems. In this review, we discuss fundamental biosensor designs and assemblies, arranging host features, transcription factors, reporter proteins, and detection methods. The progress in the genetic manipulation of iron-responsive regulatory and reporter modules is also addressed to the optimization of the biosensor performance, focusing on the improvement of sensitivity and specificity.
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Affiliation(s)
- Marzia Calvanese
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy; (M.C.); (C.D.); (M.L.T.)
- Istituto Nazionale Biostrutture e Biosistemi (I.N.B.B), Viale Medaglie D’Oro 305, 00136 Roma, Italy
| | - Caterina D’Angelo
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy; (M.C.); (C.D.); (M.L.T.)
| | - Maria Luisa Tutino
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy; (M.C.); (C.D.); (M.L.T.)
- Istituto Nazionale Biostrutture e Biosistemi (I.N.B.B), Viale Medaglie D’Oro 305, 00136 Roma, Italy
| | - Concetta Lauro
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy; (M.C.); (C.D.); (M.L.T.)
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Lamačová LJ, Trnka J. Chelating mitochondrial iron and copper: Recipes, pitfalls and promise. Mitochondrion 2024; 78:101903. [PMID: 38777220 DOI: 10.1016/j.mito.2024.101903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 05/10/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024]
Abstract
Iron and copper chelation therapy plays a crucial role in treating conditions associated with metal overload, such as hemochromatosis or Wilson's disease. However, conventional chelators face challenges in reaching the core of iron and copper metabolism - the mitochondria. Mitochondria-targeted chelators can specifically target and remove metal ions from mitochondria, showing promise in treating diseases linked to mitochondrial dysfunction, including neurodegenerative diseases and cancer. Additionally, they serve as specific mitochondrial metal sensors. However, designing these new molecules presents its own set of challenges. Depending on the chelator's intended use to prevent or to promote redox cycling of the metals, the chelating moiety must possess different donor atoms and an optimal value of the electrode potential of the chelator-metal complex. Various targeting moieties can be employed for selective delivery into the mitochondria. This review also provides an overview of the current progress in the design of mitochondria-targeted chelators and their biological activity investigation.
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Affiliation(s)
- Lucie J Lamačová
- Department of Biochemistry, Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Ruská 87, 100 00 Praha, Czech Republic
| | - Jan Trnka
- Department of Biochemistry, Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Ruská 87, 100 00 Praha, Czech Republic.
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3
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Kim H, Lee DG. Contribution of SOS genes to H 2O 2-induced apoptosis-like death in Escherichia coli. Curr Genet 2021; 67:969-980. [PMID: 34435216 DOI: 10.1007/s00294-021-01204-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 01/07/2023]
Abstract
Hydrogen peroxide (H2O2) is a debriding agent that damages the microbial structure and function by generating various reactive oxygen species (ROS). H2O2-produced hydroxyl radical (OH∙) also exerts oxidative stress on microorganisms. The spread of antibiotic-resistance in bacteria is a serious issue worldwide, and greater efforts are needed to identify and characterize novel antibacterial mechanisms to develop new treatment strategies. Therefore, this study aimed to clarify the relationship between H2O2 and Escherichia coli and to elucidate a novel antibacterial mechanism(s) of H2O2. Following H2O2 exposure, increased levels of 8-hydroxydeoxyguanosine and malondialdehyde indicated that H2O2 accelerates oxidation of bacterial DNA and lipids in E. coli. As oxidative damage worsened, the SOS response was triggered. Cell division arrest and resulting filamentous cells were identified in cells, indicating that LexA was involved in DNA replication. It was also verified that RecA, a representative SOS gene, helps self-cleavage of LexA and acts as a bacterial caspase-like protein. Our findings also showed that dinF is essential to preserve E. coli from H2O2-induced ROS, and furthermore, demonstrated that H2O2-induced SOS response and SOS genes participate differently in guarding E. coli from oxidative stress. As an extreme SOS response is considered apoptosis-like death (ALD) in bacteria, additional experiments were performed to examine the characteristics of ALD. DNA fragmentation and membrane depolarization appeared in H2O2-treated cells, suggesting that H2O2 causes ALD in E. coli. In conclusion, our investigations revealed that ALD is a novel antibacterial mode of action(s) of H2O2 with important contributions from SOS genes.
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Affiliation(s)
- Heesu Kim
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Korea
| | - Dong Gun Lee
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Korea.
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4
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Cain TJ, Smith AT. Ferric iron reductases and their contribution to unicellular ferrous iron uptake. J Inorg Biochem 2021; 218:111407. [PMID: 33684686 PMCID: PMC8035299 DOI: 10.1016/j.jinorgbio.2021.111407] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 01/29/2021] [Accepted: 02/19/2021] [Indexed: 12/21/2022]
Abstract
Iron is a necessary element for nearly all forms of life, and the ability to acquire this trace nutrient has been identified as a key virulence factor for the establishment of infection by unicellular pathogens. In the presence of O2, iron typically exists in the ferric (Fe3+) oxidation state, which is highly unstable in aqueous conditions, necessitating its sequestration into cofactors and/or host proteins to remain soluble. To counter this insolubility, and to compete with host sequestration mechanisms, many unicellular pathogens will secrete low molecular weight, high-affinity Fe3+ chelators known as siderophores. Once acquired, unicellular pathogens must liberate the siderophore-bound Fe3+ in order to assimilate this nutrient into metabolic pathways. While these organisms may hydrolyze the siderophore backbone to release the chelated Fe3+, this approach is energetically costly. Instead, iron may be liberated from the Fe3+-siderophore complex through reduction to Fe2+, which produces a lower-affinity form of iron that is highly soluble. This reduction is performed by a class of enzymes known as ferric reductases. Ferric reductases are broadly-distributed electron-transport proteins that are expressed by numerous infectious organisms and are connected to the virulence of unicellular pathogens. Despite this importance, ferric reductases remain poorly understood. This review provides an overview of our current understanding of unicellular ferric reductases (both soluble and membrane-bound), with an emphasis on the important but underappreciated connection between ferric-reductase mediated Fe3+ reduction and the transport of Fe2+ via ferrous iron transporters.
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Affiliation(s)
- Timothy J Cain
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Aaron T Smith
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD 21250, USA.
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5
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Satoh J, Kimata S, Nakamoto S, Ishii T, Tanaka E, Yumoto S, Takeda K, Yoshimura E, Kanesaki Y, Ishige T, Tanaka K, Abe A, Kawasaki S, Niimura Y. Free flavins accelerate release of ferrous iron from iron storage proteins by both free flavin-dependent and -independent ferric reductases in Escherichia coli. J GEN APPL MICROBIOL 2020; 65:308-315. [PMID: 31281172 DOI: 10.2323/jgam.2019.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ferredoxin NADP+ oxidoreductase (Fpr) and oxygen-insensitive NAD(P)H nitroreductase (NfnB) are purified from Escherichia coli JM109 (E. coli JM109) as a predominant free flavin-independent ferric reductase. In the present study, we prepared natural iron storage proteins, E. coli ferritin A (FtnA) and bacterioferritin (Bfr), to show the effective ferrous iron release from these proteins by Fpr and NfnB in the presence of free flavins. Fpr and NfnB showed flavin reductase activity for flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN) and riboflavin, and their ferrous iron release activities were positively associated with the catalytic efficiencies (kcat/Km) for individual flavins. The ferrous iron release activity of E. coli cell-free extracts was affected by flavin reductase activity of the extracts. The Butyl TOYOPEARL column chromatography of the extracts, on the basis of NAD(P)H-dependent flavin reductase activity, resulted in the separation of six active fractions containing Fpr, NfnB, NAD(P)H-quinone oxidoreductase (QOR), flavin reductase (Fre) or alkyl hydroperoxide reductase subunit F (AhpF) as major components. Like Fpr and NfnB, recombinant QOR, Fre, and AhpF showed flavin reductase activity and ferrous iron release activity in the presence of free flavins, indicating an association of flavin reductase activity with ferrous iron releasing activity. Taken together, both free flavin-dependent and free flavin-independent ferric reductases in E. coli require free flavins to mediate an electron transfer from NAD(P)H to ferric iron in the iron storage proteins for the effective ferrous iron release.
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Affiliation(s)
- Junichi Satoh
- Department of Bioscience, Tokyo University of Agriculture
| | - Shinya Kimata
- Department of Bioscience, Tokyo University of Agriculture
| | - Shota Nakamoto
- Department of Bioscience, Tokyo University of Agriculture
| | - Tatsuya Ishii
- Department of Bioscience, Tokyo University of Agriculture
| | - Eisuke Tanaka
- Department of Bioscience, Tokyo University of Agriculture
| | - Sayuri Yumoto
- Department of Bioscience, Tokyo University of Agriculture
| | - Kouji Takeda
- Education course, Tokyo University of Agriculture
| | | | - Yu Kanesaki
- Nodai Genome Research Center, Tokyo University of Agriculture
| | - Taichiro Ishige
- Nodai Genome Research Center, Tokyo University of Agriculture
| | - Keisuke Tanaka
- Nodai Genome Research Center, Tokyo University of Agriculture
| | - Akira Abe
- Department of Ophthalmology, Sapporo Medical University
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6
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Schiffels J, Selmer T. Combinatorial assembly of ferredoxin‐linked modules in
Escherichia coli
yields a testing platform for Rnf‐complexes. Biotechnol Bioeng 2019; 116:2316-2329. [DOI: 10.1002/bit.27079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/09/2019] [Accepted: 05/27/2019] [Indexed: 11/12/2022]
Affiliation(s)
- Johannes Schiffels
- Enzyme TechnologyAachen University of Applied SciencesJuelich Germany
- RWTH Aachen University, Chair of BiotechnologyWorringerweg 3 Aachen Germany
| | - Thorsten Selmer
- Enzyme TechnologyAachen University of Applied SciencesJuelich Germany
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7
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SodA Contributes to the Virulence of Avian Pathogenic Escherichia coli O2 Strain E058 in Experimentally Infected Chickens. J Bacteriol 2019; 201:JB.00625-18. [PMID: 30602490 DOI: 10.1128/jb.00625-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 12/05/2018] [Indexed: 12/18/2022] Open
Abstract
Strains of avian pathogenic Escherichia coli (APEC), the common pathogen of avian colibacillosis, encounter reactive oxygen species (ROS) during the infection process. Superoxide dismutases (SODs), acting as antioxidant factors, can protect against ROS-mediated host defenses. Our previous reports showed that the sodA gene (encoding a Mn-cofactor-containing SOD [MnSOD]) is highly expressed during the septicemic infection process of APEC. sodA has been proven to be a virulence factor of certain pathogens, but its role in the pathogenicity of APEC has not been fully identified. In this study, we deleted the sodA gene from the virulent APEC O2 strain E058 and examined the in vitro and in vivo phenotypes of the mutant. The sodA mutant was more sensitive to hydrogen peroxide in terms of both its growth and viability than was the wild type. The ability to form a biofilm was weakened in the sodA mutant. The sodA mutant was significantly more easily phagocytosed by chicken macrophages than was the wild-type strain. Chicken infection assays revealed significantly attenuated virulence of the sodA mutant compared with the wild type at 24 h postinfection. The virulence phenotype was restored by complementation of the sodA gene. Quantitative real-time reverse transcription-PCR revealed that the inactivation of sodA reduced the expression of oxidative stress response genes katE, perR, and osmC but did not affect the expression of sodB and sodC Taken together, our studies indicate that SodA is important for oxidative resistance and virulence of APEC E058.IMPORTANCE Avian colibacillosis, caused by strains of avian pathogenic Escherichia coli, is a major bacterial disease of severe economic significance to the poultry industry worldwide. The virulence mechanisms of APEC are not completely understood. This study investigated the influence of an antioxidant protein, SodA, on the phenotype and pathogenicity of APEC O2 strain E058. This is the first report demonstrating that SodA plays an important role in protecting a specific APEC strain against hydrogen peroxide-induced oxidative stress and contributes to the virulence of this pathotype strain. Identification of this virulence factor will enhance our knowledge of APEC pathogenic mechanisms, which is crucial for designing successful strategies against associated infections and transmission.
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8
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Kimata S, Mochizuki D, Satoh J, Kitano K, Kanesaki Y, Takeda K, Abe A, Kawasaki S, Niimura Y. Intracellular free flavin and its associated enzymes participate in oxygen and iron metabolism in Amphibacillus xylanus lacking a respiratory chain. FEBS Open Bio 2018; 8:947-961. [PMID: 29928575 PMCID: PMC5986008 DOI: 10.1002/2211-5463.12425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 03/10/2018] [Accepted: 03/28/2018] [Indexed: 02/06/2023] Open
Abstract
Amphibacillus xylanus is a recently identified bacterium which grows well under both aerobic and anaerobic conditions and may prove useful for biomass utilization. Amphibacillus xylanus, despite lacking a respiratory chain, consumes oxygen at a similar rate to Escherichia coli (130-140 μmol oxygen·min-1·g-1 dry cells at 37 °C), suggesting that it has an alternative system that uses a large amount of oxygen. Amphibacillus xylanus NADH oxidase (Nox) was previously reported to rapidly reduce molecular oxygen content in the presence of exogenously added free flavin. Here, we established a quantitative method for determining the intracellular concentrations of free flavins in A. xylanus, involving French pressure and ultrafiltration membranes. The intracellular concentrations of flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), and riboflavin were estimated to be approximately 8, 3, and 1 μm, respectively. In the presence of FAD, the predominant free flavin species, two flavoproteins Nox (which binds FAD) and NAD(P)H oxidoreductase (Npo, which binds FMN), were identified as central free flavin-associated enzymes in the oxygen metabolic pathway. Under 8 μm free FAD, the catalytic efficiency (kcat/Km) of recombinant Nox and Npo for oxygen increased by approximately fivefold and ninefold, respectively. Nox and Npo levels were increased, and intracellular FAD formation was stimulated following exposure of A. xylanus to oxygen. This suggests that these two enzymes and free FAD contribute to effective oxygen detoxification and NAD(P)+ regeneration to maintain redox balance during aerobic growth. Furthermore, A. xylanus required iron to grow aerobically. We also discuss the contribution of the free flavin-associated system to the process of iron utilization.
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Affiliation(s)
- Shinya Kimata
- Department of Bioscience Tokyo University of Agriculture Japan
| | | | - Junichi Satoh
- Department of Bioscience Tokyo University of Agriculture Japan
| | - Ken Kitano
- Graduate School of Biological Science Nara Institute of Science and Technology Ikoma Japan
| | - Yu Kanesaki
- Nodai Genome Research Center Tokyo University of Agriculture Japan
| | - Kouji Takeda
- Teacher Education Course Tokyo University of Agriculture Japan
| | - Akira Abe
- Department of Ophthalmology Sapporo Medical University Hokkaido Japan
| | - Shinji Kawasaki
- Department of Bioscience Tokyo University of Agriculture Japan
| | - Youichi Niimura
- Department of Bioscience Tokyo University of Agriculture Japan
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9
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Lanigan N, Bottacini F, Casey PG, O'Connell Motherway M, van Sinderen D. Genome-Wide Search for Genes Required for Bifidobacterial Growth under Iron-Limitation. Front Microbiol 2017; 8:964. [PMID: 28620359 PMCID: PMC5449479 DOI: 10.3389/fmicb.2017.00964] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 05/15/2017] [Indexed: 11/13/2022] Open
Abstract
Bacteria evolved over millennia in the presence of the vital micronutrient iron. Iron is involved in numerous processes within the cell and is essential for nearly all living organisms. The importance of iron to the survival of bacteria is obvious from the large variety of mechanisms by which iron may be acquired from the environment. Random mutagenesis and global gene expression profiling led to the identification of a number of genes, which are essential for Bifidobacterium breve UCC2003 survival under iron-restrictive conditions. These genes encode, among others, Fe-S cluster-associated proteins, a possible ferric iron reductase, a number of cell wall-associated proteins, and various DNA replication and repair proteins. In addition, our study identified several presumed iron uptake systems which were shown to be essential for B. breve UCC2003 growth under conditions of either ferric and/or ferrous iron chelation. Of these, two gene clusters encoding putative iron-uptake systems, bfeUO and sifABCDE, were further characterised, indicating that sifABCDE is involved in ferrous iron transport, while the bfeUO-encoded transport system imports both ferrous and ferric iron. Transcription studies showed that bfeUO and sifABCDE constitute two separate transcriptional units that are induced upon dipyridyl-mediated iron limitation. In the anaerobic gastrointestinal environment ferrous iron is presumed to be of most relevance, though a mutation in the sifABCDE cluster does not affect B. breve UCC2003's ability to colonise the gut of a murine model.
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Affiliation(s)
- Noreen Lanigan
- APC Microbiome Institute and School of Microbiology, University College CorkCork, Ireland
| | - Francesca Bottacini
- APC Microbiome Institute and School of Microbiology, University College CorkCork, Ireland
| | - Pat G Casey
- APC Microbiome Institute and School of Microbiology, University College CorkCork, Ireland
| | | | - Douwe van Sinderen
- APC Microbiome Institute and School of Microbiology, University College CorkCork, Ireland
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10
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Boonma S, Romsang A, Duang-Nkern J, Atichartpongkul S, Trinachartvanit W, Vattanaviboon P, Mongkolsuk S. The FinR-regulated essential gene fprA, encoding ferredoxin NADP+ reductase: Roles in superoxide-mediated stress protection and virulence of Pseudomonas aeruginosa. PLoS One 2017; 12:e0172071. [PMID: 28187184 PMCID: PMC5302815 DOI: 10.1371/journal.pone.0172071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 01/30/2017] [Indexed: 11/23/2022] Open
Abstract
Pseudomonas aeruginosa has two genes encoding ferredoxin NADP(+) reductases, denoted fprA and fprB. We show here that P. aeruginosa fprA is an essential gene. However, the ΔfprA mutant could only be successfully constructed in PAO1 strains containing an extra copy of fprA on a mini-Tn7 vector integrated into the chromosome or carrying it on a temperature-sensitive plasmid. The strain containing an extra copy of the ferredoxin gene (fdx1) could suppress the essentiality of FprA. Other ferredoxin genes could not suppress the requirement for FprA, suggesting that Fdx1 mediates the essentiality of FprA. The expression of fprA was highly induced in response to treatments with a superoxide generator, paraquat, or sodium hypochlorite (NaOCl). The induction of fprA by these treatments depended on FinR, a LysR-family transcription regulator. In vivo and in vitro analysis suggested that oxidized FinR acted as a transcriptional activator of fprA expression by binding to its regulatory box, located 20 bases upstream of the fprA -35 promoter motif. This location of the FinR box also placed it between the -35 and -10 motifs of the finR promoter, where the reduced regulator functions as a repressor. Under uninduced conditions, binding of FinR repressed its own transcription but had no effect on fprA expression. Exposure to paraquat or NaOCl converted FinR to a transcriptional activator, leading to the expression of both fprA and finR. The ΔfinR mutant showed an increased paraquat sensitivity phenotype and attenuated virulence in the Drosophila melanogaster host model. These phenotypes could be complemented by high expression of fprA, indicating that the observed phenotypes of the ΔfinR mutant arose from the inability to up-regulate fprA expression. In addition, increased expression of fprB was unable to rescue essentiality of fprA or the superoxide-sensitive phenotype of the ΔfinR mutant, suggesting distinct mechanisms of the FprA and FprB enzymes.
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Affiliation(s)
- Siriwan Boonma
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Adisak Romsang
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Jintana Duang-Nkern
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand
| | | | | | - Paiboon Vattanaviboon
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand.,Center of Excellence on Environmental Health and Toxicology, CHE, Ministry Of Education, Bangkok, Thailand.,Program in Applied Biological Sciences: Environmental Health, Chulabhorn Graduate Institute, Bangkok, Thailand
| | - Skorn Mongkolsuk
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand.,Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand.,Center of Excellence on Environmental Health and Toxicology, CHE, Ministry Of Education, Bangkok, Thailand.,Center for Emerging Bacterial Infections, Faculty of Science, Mahidol University, Bangkok, Thailand
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11
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Alcántara-Sánchez F, Leyva-Castillo LE, Chagolla-López A, González de la Vara L, Gómez-Lojero C. Distribution of isoforms of ferredoxin-NADP + reductase (FNR) in cyanobacteria in two growth conditions. Int J Biochem Cell Biol 2017; 85:123-134. [PMID: 28189842 DOI: 10.1016/j.biocel.2017.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 02/01/2017] [Accepted: 02/07/2017] [Indexed: 10/20/2022]
Abstract
Ferredoxin-NADP+ reductase (FNR) transfers reducing equivalents between ferredoxin and NADP(H) in the photosynthetic electron transport chains of chloroplasts and cyanobacteria. In most cyanobacteria, FNR is coded by a single petH gene. The structure of FNR in photosynthetic organisms can be constituted by FAD-binding and NADPH-binding domains (FNR-2D), or by these and an additional N-terminal domain (FNR-3D). In this article, biochemical evidence is provided supporting the induction of FNR-2D by iron or combined nitrogen deficiency in the cyanobacteria Synechocystis PCC 6803 and Anabaena variabilis ATCC 29413. In cell extracts of these cyanobacteria, most of FNR was associated to phycobilisomes (PBS) or phycocyanin (PC), and the rest was found as free enzyme. Free FNR activity increased in both cyanobacteria under iron stress and during diazotrophic conditions in A. variabilis. Characterization of FNR from both cyanobacteria showed that the PBS-associated enzyme was FNR-3D and the free enzyme was mostly a FNR-2D isoform. Predominant isoforms in heterocysts of A. variabilis were FNR-2D; where its N-terminal sequence lacked an initial (formyl)methionine. This means that FNR-3D is targeted to thylakoid membrane, and anchored to PBS, and FNR-2D is found as a soluble protein in the cytoplasm, when iron or fixed nitrogen deficiencies prevail in the environment. Moreover, given that Synechocystis and Anabaena variabilis are dissimilar in genotype, phenotype and ecology, the presence of these two-domain proteins in these species suggests that the mechanism of FNR induction is common among cyanobacteria regardless of their habitat and morphotype.
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Affiliation(s)
- Felipe Alcántara-Sánchez
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados-IPN, Apartado Postal 14-740, 07000 Cd de México, Mexico.
| | - Lourdes Elizabeth Leyva-Castillo
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados-IPN, Apartado Postal 14-740, 07000 Cd de México, Mexico.
| | | | | | - Carlos Gómez-Lojero
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados-IPN, Apartado Postal 14-740, 07000 Cd de México, Mexico.
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12
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Nitroreductase gene-directed enzyme prodrug therapy: insights and advances toward clinical utility. Biochem J 2015; 471:131-53. [PMID: 26431849 DOI: 10.1042/bj20150650] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
This review examines the vast catalytic and therapeutic potential offered by type I (i.e. oxygen-insensitive) nitroreductase enzymes in partnership with nitroaromatic prodrugs, with particular focus on gene-directed enzyme prodrug therapy (GDEPT; a form of cancer gene therapy). Important first indications of this potential were demonstrated over 20 years ago, for the enzyme-prodrug pairing of Escherichia coli NfsB and CB1954 [5-(aziridin-1-yl)-2,4-dinitrobenzamide]. However, it has become apparent that both the enzyme and the prodrug in this prototypical pairing have limitations that have impeded their clinical progression. Recently, substantial advances have been made in the biodiscovery and engineering of superior nitroreductase variants, in particular development of elegant high-throughput screening capabilities to enable optimization of desirable activities via directed evolution. These advances in enzymology have been paralleled by advances in medicinal chemistry, leading to the development of second- and third-generation nitroaromatic prodrugs that offer substantial advantages over CB1954 for nitroreductase GDEPT, including greater dose-potency and enhanced ability of the activated metabolite(s) to exhibit a local bystander effect. In addition to forging substantial progress towards future clinical trials, this research is supporting other fields, most notably the development and improvement of targeted cellular ablation capabilities in small animal models, such as zebrafish, to enable cell-specific physiology or regeneration studies.
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Romsang A, Duang-nkern J, Wirathorn W, Vattanaviboon P, Mongkolsuk S. Pseudomonas aeruginosa IscR-Regulated Ferredoxin NADP(+) Reductase Gene (fprB) Functions in Iron-Sulfur Cluster Biogenesis and Multiple Stress Response. PLoS One 2015; 10:e0134374. [PMID: 26230408 PMCID: PMC4521836 DOI: 10.1371/journal.pone.0134374] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Accepted: 07/08/2015] [Indexed: 12/14/2022] Open
Abstract
P. aeruginosa (PAO1) has two putative genes encoding ferredoxin NADP(+) reductases, denoted fprA and fprB. Here, the regulation of fprB expression and the protein’s physiological roles in [4Fe-4S] cluster biogenesis and stress protection are characterized. The fprB mutant has defects in [4Fe-4S] cluster biogenesis, as shown by reduced activities of [4Fe-4S] cluster-containing enzymes. Inactivation of the gene resulted in increased sensitivity to oxidative, thiol, osmotic and metal stresses compared with the PAO1 wild type. The increased sensitivity could be partially or completely suppressed by high expression of genes from the isc operon, which are involved in [Fe-S] cluster biogenesis, indicating that stress sensitivity in the fprB mutant is partially caused by a reduction in levels of [4Fe-4S] clusters. The pattern and regulation of fprB expression are in agreement with the gene physiological roles; fprB expression was highly induced by redox cycling drugs and diamide and was moderately induced by peroxides, an iron chelator and salt stress. The stress-induced expression of fprB was abolished by a deletion of the iscR gene. An IscR DNA-binding site close to fprB promoter elements was identified and confirmed by specific binding of purified IscR. Analysis of the regulation of fprB expression supports the role of IscR in directly regulating fprB transcription as a transcription activator. The combination of IscR-regulated expression of fprB and the fprB roles in response to multiple stressors emphasizes the importance of [Fe-S] cluster homeostasis in both gene regulation and stress protection.
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Affiliation(s)
- Adisak Romsang
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Jintana Duang-nkern
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand
| | - Wilaiwan Wirathorn
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Paiboon Vattanaviboon
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand
- Center of Excellence on Emerging Bacterial Infections, Faculty of Science, Mahidol University, Bangkok, Thailand
- Program in Applied Biological Science: Environmental Health, Chulabhorn Graduate Institute, Bangkok, Thailand
| | - Skorn Mongkolsuk
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok, Thailand
- Center of Excellence on Emerging Bacterial Infections, Faculty of Science, Mahidol University, Bangkok, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), Ministry Of Education, Bangkok, Thailand
- * E-mail:
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Global identification of genes affecting iron-sulfur cluster biogenesis and iron homeostasis. J Bacteriol 2014; 196:1238-49. [PMID: 24415728 DOI: 10.1128/jb.01160-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters are ubiquitous cofactors that are crucial for many physiological processes in all organisms. In Escherichia coli, assembly of Fe-S clusters depends on the activity of the iron-sulfur cluster (ISC) assembly and sulfur mobilization (SUF) apparatus. However, the underlying molecular mechanisms and the mechanisms that control Fe-S cluster biogenesis and iron homeostasis are still poorly defined. In this study, we performed a global screen to identify the factors affecting Fe-S cluster biogenesis and iron homeostasis using the Keio collection, which is a library of 3,815 single-gene E. coli knockout mutants. The approach was based on radiolabeling of the cells with [2-(14)C]dihydrouracil, which entirely depends on the activity of an Fe-S enzyme, dihydropyrimidine dehydrogenase. We identified 49 genes affecting Fe-S cluster biogenesis and/or iron homeostasis, including 23 genes important only under microaerobic/anaerobic conditions. This study defines key proteins associated with Fe-S cluster biogenesis and iron homeostasis, which will aid further understanding of the cellular mechanisms that coordinate the processes. In addition, we applied the [2-(14)C]dihydrouracil-labeling method to analyze the role of amino acid residues of an Fe-S cluster assembly scaffold (IscU) as a model of the Fe-S cluster assembly apparatus. The analysis showed that Cys37, Cys63, His105, and Cys106 are essential for the function of IscU in vivo, demonstrating the potential of the method to investigate in vivo function of proteins involved in Fe-S cluster assembly.
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15
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Miethke M. Molecular strategies of microbial iron assimilation: from high-affinity complexes to cofactor assembly systems. Metallomics 2013. [DOI: 10.1039/c2mt20193c] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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16
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Zeng X, Mo Y, Xu F, Lin J. Identification and characterization of a periplasmic trilactone esterase, Cee, revealed unique features of ferric enterobactin acquisition in Campylobacter. Mol Microbiol 2012; 87:594-608. [PMID: 23278903 DOI: 10.1111/mmi.12118] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2012] [Indexed: 11/29/2022]
Abstract
Ferric enterobactin (FeEnt) acquisition is a highly efficient and conserved iron scavenging system in Gram-negative bacteria. Recently, we have characterized two FeEnt receptors (CfrA and CfrB) in Campylobacter jejuni and C. coli, the enteric human pathogens that do not produce any siderophores. In this study, whole-genome sequencing and comparative genomic analysis identified a unique Ent trilactone esterase Cee (Cj1376) in C. jejuni. Genomic analysis and biochemical assay strongly suggested that Cee is the sole trilactone esterase in C. jejuni. Thin-layer chromatography and HPLC analyses showed high efficiency of the purified Cee to hydrolyse Ent. Three Cee homologues previously characterized from other bacteria (IroE, IroD and Fes) were also purified and analysed together with Cee, indicating that Cee, Fes and IroD displayed similar hydrolysis dynamics for both apo and ferric forms of Ent while IroE catalysed Ent inefficiently. Unlike cytoplasmic Fes and IroD, Cee is localized in the periplasm as demonstrated by immunoblotting using Cee-specific antibodies. Genetic manipulation of diverse Campylobacter strains demonstrated that Cee is not only essential for CfrB-dependent FeEnt acquisition but also involved in CfrA-dependent pathway. Together, this study identified and characterized a novel periplasmic trilactone esterase and suggested a new model of FeEnt acquisition in Campylobacter.
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Affiliation(s)
- Ximin Zeng
- Department of Animal Science, The University of Tennessee, Knoxville, TN 37996, USA
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Catalano-Dupuy DL, Musumeci MA, López-Rivero A, Ceccarelli EA. A highly stable plastidic-type ferredoxin-NADP(H) reductase in the pathogenic bacterium Leptospira interrogans. PLoS One 2011; 6:e26736. [PMID: 22039544 PMCID: PMC3200346 DOI: 10.1371/journal.pone.0026736] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 10/03/2011] [Indexed: 01/18/2023] Open
Abstract
Leptospira interrogans is a bacterium that is capable of infecting animals and humans, and its infection causes leptospirosis with a range of symptoms from flu-like to severe illness and death. Despite being a bacteria, Leptospira interrogans contains a plastidic class ferredoxin-NADP(H) reductase (FNR) with high catalytic efficiency, at difference from the bacterial class FNRs. These flavoenzymes catalyze the electron transfer between NADP(H) and ferredoxins or flavodoxins. The inclusion of a plastidic FNR in Leptospira metabolism and in its parasitic life cycle is not currently understood. Bioinformatic analyses of the available genomic and proteins sequences showed that the presence of this enzyme in nonphotosynthetic bacteria is restricted to the Leptospira genus and that a [4Fe-4S] ferredoxin (LB107) encoded by the Leptospira genome may be the natural substrate of the enzyme. Leptospira FNR (LepFNR) displayed high diaphorase activity using artificial acceptors and functioned as a ferric reductase. LepFNR displayed cytochrome c reductase activity with the Leptospira LB107 ferredoxin with an optimum at pH 6.5. Structural stability analysis demonstrates that LepFNR is one of the most stable FNRs analyzed to date. The persistence of a native folded LepFNR structure was detected in up to 6 M urea, a condition in which the enzyme retains 38% activity. In silico analysis indicates that the high LepFNR stability might be due to robust interactions between the FAD and the NADP+ domains of the protein. The limited bacterial distribution of plastidic class FNRs and the biochemical and structural properties of LepFNR emphasize the uniqueness of this enzyme in the Leptospira metabolism. Our studies show that in L. interrogans a plastidic-type FNR exchanges electrons with a bacterial-type ferredoxin, process which has not been previously observed in nature.
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Affiliation(s)
- Daniela L Catalano-Dupuy
- Molecular Biology Division, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
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18
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Synechocystis ferredoxin-NADP+ oxidoreductase is capable of functioning as ferric reductase and of driving the Fenton reaction in the absence or presence of free flavin. Biometals 2011; 24:311-21. [DOI: 10.1007/s10534-010-9397-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 12/08/2010] [Indexed: 11/25/2022]
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Miethke M, Pierik AJ, Peuckert F, Seubert A, Marahiel MA. Identification and characterization of a novel-type ferric siderophore reductase from a gram-positive extremophile. J Biol Chem 2010; 286:2245-60. [PMID: 21051545 DOI: 10.1074/jbc.m110.192468] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Iron limitation is one major constraint of microbial life, and a plethora of microbes use siderophores for high affinity iron acquisition. Because specific enzymes for reductive iron release in gram-positives are not known, we searched Firmicute genomes and found a novel association pattern of putative ferric siderophore reductases and uptake genes. The reductase from the schizokinen-producing alkaliphile Bacillus halodurans was found to cluster with a ferric citrate-hydroxamate uptake system and to catalyze iron release efficiently from Fe[III]-dicitrate, Fe[III]-schizokinen, Fe[III]-aerobactin, and ferrichrome. The gene was hence named fchR for ferric citrate and hydroxamate reductase. The tightly bound [2Fe-2S] cofactor of FchR was identified by UV-visible, EPR, CD spectroscopy, and mass spectrometry. Iron release kinetics were determined with several substrates by using ferredoxin as electron donor. Catalytic efficiencies were strongly enhanced in the presence of an iron-sulfur scaffold protein scavenging the released ferrous iron. Competitive inhibition of FchR was observed with Ga(III)-charged siderophores with K(i) values in the micromolar range. The principal catalytic mechanism was found to couple increasing K(m) and K(D) values of substrate binding with increasing k(cat) values, resulting in high catalytic efficiencies over a wide redox range. Physiologically, a chromosomal fchR deletion led to strongly impaired growth during iron limitation even in the presence of ferric siderophores. Inductively coupled plasma-MS analysis of ΔfchR revealed intracellular iron accumulation, indicating that the ferric substrates were not efficiently metabolized. We further show that FchR can be efficiently inhibited by redox-inert siderophore mimics in vivo, suggesting that substrate-specific ferric siderophore reductases may present future targets for microbial pathogen control.
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Affiliation(s)
- Marcus Miethke
- Fachbereich Chemie/Biochemie, Philipps Universität Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
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