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Hider RC, Silva AMN, Cilibrizzi A. The iron(III) coordinating properties of citrate and α-hydroxycarboxylate containing siderophores. Biometals 2024:10.1007/s10534-024-00607-z. [PMID: 38773014 DOI: 10.1007/s10534-024-00607-z] [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: 02/28/2024] [Accepted: 05/05/2024] [Indexed: 05/23/2024]
Abstract
The iron(III) binding properties of citrate and rhizoferrin, a citrate containing siderophore, are compared. Citrate forms many oligonuclear complexes, whereas rhizoferrin forms a single mononuclear complex. The α-hydroxycarboxylate functional group, which is present in both citrate, and rhizoferrin, has a high affinity and selectivity for iron(III) under most biological conditions. The nature of the toxic form of iron found in the blood of patients suffering from many haemoglobinopathies and haemochromatosis is identified as a mixture of iron(III)citrate complexes. The significance of the presence of this iron pool to patients suffering from systemic iron overload is discussed. The wide utilisation of the α-hydroxycarboxylate functional group in siderophore structures is described, as is their photo-induced decarboxylation leading to the release of iron(II) ions. The importance of this facile dissociation to algal iron uptake is discussed.
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Affiliation(s)
- Robert C Hider
- Institute of Pharmaceutical Science, King's College London, London, SE1 9NH, UK.
| | - André M N Silva
- LAQV-REQUIMTE, Departamento de Quimica E Bioquimica, Faculdade de Ciencias, Universidade Do Porto, Rua Do Campo Alegre, S/N, 4169-007, Porto, Portugal
| | - Agostino Cilibrizzi
- Institute of Pharmaceutical Science, King's College London, London, SE1 9NH, UK
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2
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Négrel S, Brunel JM. Synthesis and Biological Activities of Naturally Functionalized Polyamines: An Overview. Curr Med Chem 2021; 28:3406-3448. [PMID: 33138746 DOI: 10.2174/0929867327666201102114544] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 09/01/2020] [Accepted: 09/16/2020] [Indexed: 11/22/2022]
Abstract
Recently, extensive researches have emphasized the fact that polyamine conjugates are becoming important in all biological and medicinal fields. In this review, we will focus our attention on natural polyamines and highlight recent progress in both fundamental mechanism studies and interests in the development and application for the therapeutic use of polyamine derivatives.
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Affiliation(s)
- Sophie Négrel
- Aix Marseille University, Faculty of Pharmacy, UMR-MD1, 27 bd Jean Moulin, 13385 Marseille, France
| | - Jean Michel Brunel
- Aix Marseille University, Faculty of Pharmacy, UMR-MD1, 27 bd Jean Moulin, 13385 Marseille, France
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3
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Dangi V, Baral M, Kanungo BK. Photophysical Studies of a Catechol Based Polyfunctional Dipodal Chelator: Application for Optical Probe for Selective Detection of Fe(III). J Fluoresc 2020; 30:1131-1149. [PMID: 32648173 DOI: 10.1007/s10895-020-02583-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/30/2020] [Indexed: 10/23/2022]
Abstract
A novel catechol based dipodal fluorescent chelator N,N'-bis[3-[(E)-(2,3-dihydroxyphenyl)methyleneamino]propyl]propanediamide(MPC), has been developed and its photophysical behaviour was studied by experimental (UV-VIS and fluorescence) and DFT method. The design of the molecule has been inspired from the naturally occurring siderophore enterobactin, a catechol based chelator with amide linkage, that shows an excellent binding efficiency towards Fe(III). The dipodal molecule (MPC) presented here, carries two catechol pendant binding moieties linked to the malonate central unit through propylene spacers by amide linkage. MPC showed good selectivity for Fe(III) at 10-4 M concentration in aqueous medium amongst the biologically and environmentally important metal ions chosen viz., Na(I), K(I), Al(III), Cr(III), Fe(III), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II), by demonstrating a remarkable quenching in the fluorescent emission from 262 a.u. to 55 a.u. at λmax = 477 nm. Also, the pre-organized assembled ligand favored an efficient Fe (III) encapsulation through coordination by imine nitrogen and catecholate oxygen donors. High formation constant (log β = 31.3) for 1:1 metal-ligand complex evaluated by both potentiometric and spectrophotometric methods, established the strong binding efficiency of the ligand for Fe(III) metal ion. The binding stoichiometry in the complex was also confirmed from Stern -Volmer and Hill Plot analysis. Further investigation on the emission behavior of MPC in a completely DMSO system explored its suitability for extensive applications in the areas such as, metallurgy, material science, iron contamination remedial in the materials etc.. DFT studies suggest that the ligand displays a U-shaped geometry with a parallel π-stacking and the hydrogen bond between two arms. The experimental infrared, electronic, fluorescence, 1H nmr, 13C nmr spectra were correlated with the theoretical results. The nature of electronic transitions were identified from the TDDFT calculation. The ligand forms a hexa-coordinated complex with six Fe-O bonds extending an orthorhombic geometry due distortion from a regular octahedron.
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Affiliation(s)
- Vijay Dangi
- Department of Chemistry, National Institute of Technology, Kurukshetra, Haryana, 136119, India
| | - Minati Baral
- Department of Chemistry, National Institute of Technology, Kurukshetra, Haryana, 136119, India.
| | - B K Kanungo
- Department of Chemistry, Sant Longowal Institute of Engineering & Technology, Longowal, 148106, India
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4
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Dauner M, Skerra A. Scavenging Bacterial Siderophores with Engineered Lipocalin Proteins as an Alternative Antimicrobial Strategy. Chembiochem 2019; 21:601-606. [PMID: 31613035 PMCID: PMC7079049 DOI: 10.1002/cbic.201900564] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Indexed: 12/30/2022]
Abstract
Iron acquisition mediated by siderophores, high-affinity chelators for which bacteria have evolved specific synthesis and uptake mechanisms, plays a crucial role in microbiology and in host-pathogen interactions. In the ongoing fight against bacterial infections, this area has attracted biomedical interest. Beyond several approaches to interfere with siderophore-mediated iron uptake from medicinal and immunochemistry, the development of high-affinity protein scavengers that tightly complex the siderophores produced by pathogenic bacteria has appeared as a novel strategy. Such binding proteins have been engineered based on siderocalin-also known as lipocalin 2-an endogenous human scavenger of enterobactin and bacillibactin that controls the systemic spreading of commensal bacteria such as Escherichia coli. By using combinatorial protein design, siderocalin was reshaped to bind several siderophores from Pseudomonas aeruginosa and, in particular, petrobactin from Bacillus anthracis, none of which is recognized by the natural protein. Such engineered versions of siderocalin effectively suppress the growth of corresponding pathogenic bacteria by depriving them of their iron supply and offer the potential to complement antibiotic therapy in situations of acute or persistent infection.
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Affiliation(s)
- Martin Dauner
- Institut für Biochemie und Biotechnologie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Strasse 3a, 06120, Halle/Saale, Germany
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354, Freising, Germany
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Garzón-Posse F, Quevedo-Acosta Y, Mahecha-Mahecha C, Acosta-Guzmán P. Recent Progress in the Synthesis of Naturally Occurring Siderophores. European J Org Chem 2019. [DOI: 10.1002/ejoc.201901257] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Fabián Garzón-Posse
- Laboratory of Organic Synthesis; Bio and Organocatalysis; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
| | - Yovanny Quevedo-Acosta
- Laboratory of Organic Synthesis; Bio and Organocatalysis Chemistry Department; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
- Institute of Chemistry; Bio and Organocatalysis Chemistry Department; State University of Campinas; Rua Monteiro Lobato 270 13083-862 Campinas Brazil
| | - Camilo Mahecha-Mahecha
- Laboratory of Organic Synthesis; Bio and Organocatalysis Chemistry Department; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
| | - Paola Acosta-Guzmán
- Laboratory of Organic Synthesis; Bio and Organocatalysis Chemistry Department; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
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Dauner M, Eichinger A, Lücking G, Scherer S, Skerra A. Neuprogrammierung von humanem Siderocalin zur Neutralisierung von Petrobactin, dem essenziellen Eisenfänger des Milzbrand-Bazillus. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201807442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Martin Dauner
- Lehrstuhl für Biologische Chemie; Technische Universität München; Emil-Erlenmeyer-Forum 5 85354 Freising Deutschland
| | - Andreas Eichinger
- Lehrstuhl für Biologische Chemie; Technische Universität München; Emil-Erlenmeyer-Forum 5 85354 Freising Deutschland
| | - Genia Lücking
- Lehrstuhl für Mikrobielle Ökologie; Technische Universität München; Weihenstephaner Berg 3 85354 Freising Deutschland
| | - Siegfried Scherer
- Lehrstuhl für Mikrobielle Ökologie; Technische Universität München; Weihenstephaner Berg 3 85354 Freising Deutschland
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie; Technische Universität München; Emil-Erlenmeyer-Forum 5 85354 Freising Deutschland
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7
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Dauner M, Eichinger A, Lücking G, Scherer S, Skerra A. Reprogramming Human Siderocalin To Neutralize Petrobactin, the Essential Iron Scavenger of Anthrax Bacillus. Angew Chem Int Ed Engl 2018; 57:14619-14623. [DOI: 10.1002/anie.201807442] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Martin Dauner
- Lehrstuhl für Biologische Chemie; Technische Universität München; Emil-Erlenmeyer-Forum 5 85354 Freising Germany
| | - Andreas Eichinger
- Lehrstuhl für Biologische Chemie; Technische Universität München; Emil-Erlenmeyer-Forum 5 85354 Freising Germany
| | - Genia Lücking
- Lehrstuhl für Mikrobielle Ökologie; Technische Universität München; Weihenstephaner Berg 3 85354 Freising Germany
| | - Siegfried Scherer
- Lehrstuhl für Mikrobielle Ökologie; Technische Universität München; Weihenstephaner Berg 3 85354 Freising Germany
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie; Technische Universität München; Emil-Erlenmeyer-Forum 5 85354 Freising Germany
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8
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Azomethine-H as a highly selective fluorescent probe for Fe3+ detection in 100% aqueous solution and its application in living cell imaging. Chem Res Chin Univ 2015. [DOI: 10.1007/s40242-015-5163-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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9
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Bergeron RJ, Wiegand J, McManis JS, Bharti N. Desferrithiocin: a search for clinically effective iron chelators. J Med Chem 2014; 57:9259-91. [PMID: 25207964 PMCID: PMC4255733 DOI: 10.1021/jm500828f] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Indexed: 01/19/2023]
Abstract
The successful search for orally active iron chelators to treat transfusional iron-overload diseases, e.g., thalassemia, is overviewed. The critical role of iron in nature as a redox engine is first described, as well as how primitive life forms and humans manage the metal. The problems that derive when iron homeostasis in humans is disrupted and the mechanism of the ensuing damage, uncontrolled Fenton chemistry, are discussed. The solution to the problem, chelator-mediated iron removal, is clear. Design options for the assembly of ligands that sequester and decorporate iron are reviewed, along with the shortcomings of the currently available therapeutics. The rationale for choosing desferrithiocin, a natural product iron chelator (a siderophore), as a platform for structure-activity relationship studies in the search for an orally active iron chelator is thoroughly developed. The study provides an excellent example of how to systematically reengineer a pharmacophore in order to overcome toxicological problems while maintaining iron clearing efficacy and has led to three ligands being evaluated in human clinical trials.
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Affiliation(s)
- Raymond J. Bergeron
- Department of Medicinal Chemistry, University of Florida, Box 100485 JHMHC, Gainesville, Florida 32610-0485, United States
| | - Jan Wiegand
- Department of Medicinal Chemistry, University of Florida, Box 100485 JHMHC, Gainesville, Florida 32610-0485, United States
| | - James S. McManis
- Department of Medicinal Chemistry, University of Florida, Box 100485 JHMHC, Gainesville, Florida 32610-0485, United States
| | - Neelam Bharti
- Department of Medicinal Chemistry, University of Florida, Box 100485 JHMHC, Gainesville, Florida 32610-0485, United States
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Bugdahn N, Oberthür M. Syntheses and Iron Binding Affinities of theBacillus anthracisSiderophore Petrobactin and Sidechain-Modified Analogues. European J Org Chem 2013. [DOI: 10.1002/ejoc.201301340] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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11
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Zane HK, Butler A. Isolation, structure elucidation, and iron-binding properties of lystabactins, siderophores isolated from a marine Pseudoalteromonas sp. JOURNAL OF NATURAL PRODUCTS 2013; 76:648-654. [PMID: 23444833 DOI: 10.1021/np3008655] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The marine bacterium Pseudoalteromonas sp. S2B, isolated from the Gulf of Mexico after the Deepwater Horizon oil spill, was found to produce lystabactins A, B, and C (1-3), three new siderophores. The structures were elucidated through mass spectrometry, amino acid analysis, and NMR. The lystabactins are composed of serine (Ser), asparagine (Asn), two formylated/hydroxylated ornithines (FOHOrn), dihydroxy benzoic acid (Dhb), and a very unusual nonproteinogenic amino acid, 4,8-diamino-3-hydroxyoctanoic acid (LySta). The iron-binding properties of the compounds were investigated through a spectrophotometric competition.
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Affiliation(s)
- Hannah K Zane
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
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12
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Efficient synthesis of the siderophore petrobactin via antimony triethoxide mediated coupling. Tetrahedron Lett 2012. [DOI: 10.1016/j.tetlet.2012.01.074] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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13
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Marenco MJC, Fowley C, Hyland BW, Galindo-Riaño D, Sahoo SK, Callan JF. A New Fluorescent Sensor for the Determination of Iron(III) in Semi-Aqueous Solution. J Fluoresc 2011; 22:795-8. [DOI: 10.1007/s10895-011-1015-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 10/21/2011] [Indexed: 11/30/2022]
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14
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Schmelz S, Botting CH, Song L, Kadi NF, Challis GL, Naismith JH. Structural basis for acyl acceptor specificity in the achromobactin biosynthetic enzyme AcsD. J Mol Biol 2011; 412:495-504. [PMID: 21835184 PMCID: PMC3323832 DOI: 10.1016/j.jmb.2011.07.059] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 07/25/2011] [Accepted: 07/26/2011] [Indexed: 11/17/2022]
Abstract
Siderophores are known virulence factors, and their biosynthesis is a target for new antibacterial agents. A non-ribosomal peptide synthetase-independent siderophore biosynthetic pathway in Dickeya dadantii is responsible for production of the siderophore achromobactin. The D. dadantii achromobactin biosynthesis protein D (AcsD) enzyme has been shown to enantioselectively esterify citric acid with l-serine in the first committed step of achromobactin biosynthesis. The reaction occurs in two steps: stereospecific activation of citric acid by adenylation, followed by attack of the enzyme-bound citryl adenylate by l-serine to produce the homochiral ester. We now report a detailed characterization of the substrate profile and mechanism of the second (acyl transfer) step of AcsD enzyme. We demonstrate that the enzyme catalyzes formation of not only esters but also amides from the citryl-adenylate intermediate. We have rationalized the substrate utilization profile for the acylation reaction by determining the first X-ray crystal structure of a product complex for this enzyme class. We have identified the residues that are important for both recognition of l-serine and catalysis of ester formation. Our hypotheses were tested by biochemical analysis of various mutants, one of which shows a reversal of specificity from the wild type with respect to non-natural substrates. This change can be rationalized on the basis of our structural data. That this change in specificity is accompanied by no loss in activity suggests that AcsD and other members of the non-ribosomal peptide synthetase-independent siderophore superfamily may have biotransformation potential.
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Affiliation(s)
- Stefan Schmelz
- Scottish Structural Proteomics Facility and Centre for Biomolecular Sciences, The University of St Andrews, Scotland KY16 9ST, UK
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15
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Bergeron RJ, Singh S, Bharti N. Synthesis of Heterobactins A and B and Nocardia Heterobactin. Tetrahedron 2011; 67:3163-3169. [PMID: 22539866 PMCID: PMC3334306 DOI: 10.1016/j.tet.2011.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The synthesis of the Rhodococcus erythropolis siderophores heterobactins A and B, and the structurally related Nocardia heterobactin, is described. Two approaches for the assembly of these asymmetric ligand donor chelators are explored. In the first approach, a scheme predicated on the biosynthesis of the Paracoccus denitrificans siderophore, parabactin, is employed. In this approach, the central donor synthon is added last. In the second scheme, the central donor and the terminal 2,3-dihydroxybenzoyl fragment are first fixed to the ligand's D-ornithine backbone. This is followed by condensation with the cyclic ornithine hydroxamate glycine segment. The schemes offer a flexible approach to other heterobactins. Job's plots suggest that heterobactin A and Nocardia heterobactin form 1:1 ligand/metal complexes, while heterobactin B forms a 3:2 ligand/metal complex.
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Affiliation(s)
- Raymond J Bergeron
- Box 100485, Department of Medicinal Chemistry, University of Florida, Gainesville, FL, 32610-0485
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16
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Sonier MB, Weger HG. Plasma membrane ferric reductase activity of iron-limited algal cells is inhibited by ferric chelators. Biometals 2010; 23:1029-42. [PMID: 20508972 DOI: 10.1007/s10534-010-9348-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 05/17/2010] [Indexed: 10/19/2022]
Abstract
Iron-limited cells of the green alga Chlorella kesslerii use a reductive mechanism to acquire Fe(III) from the extracellular environment, in which a plasma membrane ferric reductase reduces Fe(III)-chelates to Fe(II), which is subsequently taken up by the cell. Previous work has demonstrated that synthetic chelators both support ferric reductase activity (when supplied as Fe(III)-chelates) and inhibit ferric reductase. In the present set of experiments we extend these observations to naturally-occurring chelators and their analogues (desferrioxamine B mesylate, schizokinen, two forms of dihydroxybenzoic acid) and also two formulations of the commonly-used herbicide N-(phoshonomethyl)glycine (glyphosate). The ferric forms of the larger siderophores (desferrioxamine B mesylate, schizokinen) and Fe(III)-N-(phoshonomethyl)glycine (as the isopropylamine salt) all supported rapid rates of ferric reductase activity, while the iron-free forms inhibited reductase activity. The smaller siderophores/siderophore precursors, 2,3- and 3,4-dihydroxybenzoic acids, did not support high rates of reductase in the ferric form but did inhibit reductase activity in the iron-free form. Bioassays indicated that Fe(III)-chelates that supported high rates of ferric reductase activity also supported a large stimulation in the growth of iron-limited cells, and that an excess of iron-free chelator decreased the growth rate. With respect to N-(phosphonomethyl)glycine, there were differences between the pure compound (free acid form) and the most common commercial formulation (which also contains isopropylamine) in terms of supporting and inhibiting ferric reductase activity and growth. Overall, these results suggest that photosynthetic organisms that use a reductive strategy for iron acquisition both require, and are potentially simultaneously inhibited by, ferric chelators. Furthermore, these results also may provide an explanation for the frequently contradictory results of N-(phosphonomethyl)glycine application to crops: we suggest that low concentrations of this molecule likely solubilize Fe(III), making it available for plant growth, but that higher (but sub-lethal) concentrations decrease iron acquisition by inhibiting ferric reductase activity.
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Affiliation(s)
- Mathew B Sonier
- Department of Biology, University of Regina, Regina, SK, S4S 0A2, Canada
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Bugdahn N, Peuckert F, Albrecht AG, Miethke M, Marahiel MA, Oberthür M. Direkte Identifizierung eines Siderophor-Importproteins durch synthetische Petrobactinliganden. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201005527] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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18
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Bugdahn N, Peuckert F, Albrecht AG, Miethke M, Marahiel MA, Oberthür M. Direct Identification of a Siderophore Import Protein Using Synthetic Petrobactin Ligands. Angew Chem Int Ed Engl 2010; 49:10210-3. [DOI: 10.1002/anie.201005527] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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19
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Single sensor for multiple analytes: chromogenic detection of I− and fluorescent detection of Fe3+. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.05.105] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Butler A, Theisen RM. Iron(III)-siderophore coordination chemistry: Reactivity of marine siderophores. Coord Chem Rev 2010; 254:288-296. [PMID: 21442004 PMCID: PMC3062850 DOI: 10.1016/j.ccr.2009.09.010] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two remarkable features of many siderophores produced by oceanic bacteria are the prevalence of an α-hydroxy-carboxylic acid functionality either in the form of the amino acid β-hydroxy aspartic acid or in the form of citric acid, as well as the predominance of amphiphilic siderophores. This review will provide an overview of the photoreactivity that takes place when siderophores containing β-hydroxy aspartic acid and citric acid are coordinated to iron(III). This photoreactivity raises questions about the role of this photochemistry in microbial iron acquisition as well as upper-ocean iron cycling. The self-assembly of amphiphilic siderophores and the coordination-induced phase-change of the micelle-to-vesicle transformation will also be reviewed. The distinctive photosensitive and self-assembly properties of marine siderophores hint at possibly new microbial iron acquisition mechanisms.
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Affiliation(s)
- Alison Butler
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA 93106-9510, United States
| | - Roslyn M. Theisen
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA 93106-9510, United States
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22
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Zhang G, Amin SA, Küpper FC, Holt PD, Carrano CJ, Butler A. Ferric stability constants of representative marine siderophores: marinobactins, aquachelins, and petrobactin. Inorg Chem 2009; 48:11466-73. [PMID: 19902959 PMCID: PMC2790009 DOI: 10.1021/ic901739m] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The coordination of iron(III) to the marine amphiphilic marinobactin and aquachelin siderophores, as well as to petrobactin, an unusual 3,4-dihydroxybenzoyl siderophore is reported. Potentiometric titrations were performed on the apo siderophore to determine the ligand pK(a) values, as well as the complex formed with addition of 1 equiv of Fe(III). The log K(ML) values for Fe(III)-marinobactin-E and Fe(III)-aquachelin-C are 31.80 and 31.4, respectively, consistent with the similar coordination environment in each complex, while log K(ML) for Fe(III)-petrobactin is estimated to be about 43. The pK(a) of the beta-hydroxyaspartyl hydroxyl group was determined to be 10.8 by (1)H NMR titration. (13)C NMR and IR spectroscopy were used to investigate Ga(III) coordination to the marinobactins. The coordination-induced shifts (CIS) in the (13)C NMR spectrum of Ga(III)-marinobactin-C compared to apo-marinobactin-C indicates that the hydroxamate groups are coordinated to Ga(III); however, the lack of CISs for the carbons of the beta-hydroxyamide group suggests this moiety is not coordinated in the Ga(III) complex. Differences in the IR spectrum of Ga(III)-marinobactin-C and Fe(III)-marinobactin-C in the 1600-1700 cm(-1) region also corroborates Fe(III) is coordinated to the beta-hydroxyamide moiety, whereas Ga(III) is not coordinated.
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Affiliation(s)
- Guangping Zhang
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 and Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030
| | - Shady A. Amin
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 and Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030
| | - Frithjof C. Küpper
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 and Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030
| | - Pamela D. Holt
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 and Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030
| | - Carl J. Carrano
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 and Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030
| | - Alison Butler
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510 and Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA 92182-1030
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Wilson MK, Abergel RJ, Arceneaux JEL, Raymond KN, Byers BR. Temporal production of the two Bacillus anthracis siderophores, petrobactin and bacillibactin. Biometals 2009; 23:129-34. [PMID: 19816776 DOI: 10.1007/s10534-009-9272-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 09/23/2009] [Indexed: 01/26/2023]
Abstract
Bacillus anthracis secretes two siderophores, petrobactin (PB) and bacillibactin (BB). These siderophores were temporally produced during germination and outgrowth of spores (the usual infectious form of B. anthracis) in low-iron medium. The siderophore PB was made first while BB secretion began several hours later. Spore outgrowth early in an infection may require PB, whereas delayed BB production suggests a role for BB in the later stages of the infection. Incubation of cultures (inoculated as vegetative cells) at 37 degrees C, as compared to 2 degrees C, increased PB production and decreased secretion of BB, suggesting that the production of PB and BB responded to the host temperature signal. The dual siderophores of B. anthracis may fulfill independent roles in the life cycle of B. anthracis.
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Affiliation(s)
- Melissa K Wilson
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS 39216, USA
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Affiliation(s)
- Moriah Sandy
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, USA
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25
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Sufrin JR, Finckbeiner S, Oliver CM. Marine-derived metabolites of S-adenosylmethionine as templates for new anti-infectives. Mar Drugs 2009; 7:401-34. [PMID: 19841722 PMCID: PMC2763108 DOI: 10.3390/md7030401] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 08/20/2009] [Accepted: 08/24/2009] [Indexed: 12/24/2022] Open
Abstract
S-Adenosylmethionine (AdoMet) is a key biochemical co-factor whose proximate metabolites include methylated macromolecules (e.g., nucleic acids, proteins, phospholipids), methylated small molecules (e.g., sterols, biogenic amines), polyamines (e.g., spermidine, spermine), ethylene, and N-acyl-homoserine lactones. Marine organisms produce numerous AdoMet metabolites whose novel structures can be regarded as lead compounds for anti-infective drug design.
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Affiliation(s)
- Janice R. Sufrin
- Department of Pharmacology and Therapeutics, Grace Cancer Drug Center, Roswell Park Cancer Institute, Buffalo, New York, NY, USA; E-Mails: (S.F.); (C.O.)
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Holinsworth B, Martin JD. Siderophore production by marine-derived fungi. Biometals 2009; 22:625-32. [PMID: 19350395 PMCID: PMC2706916 DOI: 10.1007/s10534-009-9239-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Accepted: 03/23/2009] [Indexed: 10/20/2022]
Abstract
Siderophore production by marine-derived fungi has not been extensively explored. Three studies have investigated the ability of marine-derived fungi to produce siderophores in response to iron limitation [(Vala et al. in Indian J Mar Sci 29:339-340, 2000; Can J Microbiol 52:603-607, 2006); Baakza et al. in J Exp Mar Biol Ecol 311:1-9, 2004]. In all, 24 of 28 marine fungal strains were found to secrete hydroxamate or carboxylate siderophores; no evidence was found for production of catecholate siderophores. These studies did not determine the structures of the iron-binding compounds. More recently, a study of the natural products secreted by a marine Penicillium bilaii revealed that this strain produced the rare catecholate siderophore pistillarin when grown under relatively high iron concentrations (Capon et al. J Nat Prod 70:1746-1752, 2007). Additionally, the production of rhizoferrin by a marine isolate of Cunninghamella elegans (ATCC36112) is reported in this manuscript. The current state of knowledge about marine fungal siderophores is reviewed in light of these promising results.
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Affiliation(s)
- Brian Holinsworth
- Department of Natural Sciences, Northeastern State University, 611 N. Grand Ave., Tahlequah, OK 74464
| | - Jessica D. Martin
- Department of Natural Sciences, Northeastern State University, 611 N. Grand Ave., Tahlequah, OK 74464
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27
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Ye YQ, Koshino H, Onose JI, Negishi C, Yoshikawa K, Abe N, Takahashi S. Structural Revision of Thelephantin G by Total Synthesis and the Inhibitory Activity against TNF-α Production. J Org Chem 2009; 74:4642-5. [DOI: 10.1021/jo900638b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yue Qi Ye
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Hiroyuki Koshino
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Jun-ichi Onose
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Chiemi Negishi
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Kunie Yoshikawa
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Naoki Abe
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Shunya Takahashi
- RIKEN, Wako, Saitama 351-0198, Japan, and Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
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28
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Siderophores of Marinobacter aquaeolei: petrobactin and its sulfonated derivatives. Biometals 2009; 22:565-71. [PMID: 19357970 DOI: 10.1007/s10534-009-9237-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Accepted: 03/23/2009] [Indexed: 10/20/2022]
Abstract
Siderophores are low molecular weight, high-affinity iron(III) ligands, produced by bacteria to solubilize and promote iron uptake under low iron conditions. Two prominent structural features characterize the majority of the marine siderophores discovered so far: (1) a predominance of suites of amphiphilic siderophores composed of an iron(III)-binding headgroup that is appended by one or two of a series of fatty acids and (2) a prevalence of siderophores that contain alpha-hydroxycarboxylic acid moieties (e.g., beta-hydroxyaspartic acid or citric acid) which are photoreactive when coordinated to Fe(III). Variation of the fatty acid chain length affects the relative amphiphilicity within a suite of siderophores. Catecholate sulfonation is another structural variation that would affect the hydrophilicity of a siderophore. In addition to a review of the marine amphiphilic siderophores, we report the production of petrobactin disulfonate by Marinobacter aquaeolei VT8.
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Singh N, Kaur N, Callan JF. Incorporation of Siderophore Binding Sites in a Dipodal Fluorescent Sensor for Fe(III). J Fluoresc 2009; 19:649-54. [DOI: 10.1007/s10895-008-0457-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Accepted: 12/16/2008] [Indexed: 10/21/2022]
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Kadi N, Challis GL. Chapter 17. Siderophore biosynthesis a substrate specificity assay for nonribosomal peptide synthetase-independent siderophore synthetases involving trapping of acyl-adenylate intermediates with hydroxylamine. Methods Enzymol 2009; 458:431-57. [PMID: 19374993 DOI: 10.1016/s0076-6879(09)04817-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Siderophores are an important group of structurally diverse natural products that play key roles in ferric iron acquisition in most microorganisms. Two major pathways exist for siderophore biosynthesis. One is dependent on nonribosomal peptide synthetase (NRPS) multienzymes. The enzymology of several NRPS-dependent pathways to structurally diverse siderophores has been intensively studied for more than 10 years and is generally well understood. The other major pathway is NRPS-independent. It relies on a novel family of synthetase enzymes that until recently has received very little attention. Over the last 2 years, these enzymes have begun to be intensively investigated and several examples have now been characterized. In this article, we give an overview of the enzymology of NRPS-dependent and NRPS-independent pathways for siderophore biosynthesis, using selected examples to highlight key features. An important facet of many studies of the enzymology of siderophore biosynthesis has been to investigate the substrate specificity of the synthetase enzymes involved. For NRPS-dependent pathways, the ATP-pyrophophate exchange assay has been widely used to investigate the substrate specificity of adenylation domains within the synthetase multienzymes. This assay is ineffective for NRPS-independent siderophore (NIS) synthetases, probably because pyrophosphate is not released from the enzyme after the carboxylic acid substrate and ATP react to form an acyl adenylate. An alternative assay for enzymes that form acyl adenylates involves trapping of the activated carboxyl group with hydroxylamine to form a hydroxamic acid that can be converted to its ferric complex and detected spectrophotometrically. This assay has not been widely used for NRPS adenylation domains. Here, we show that it is an effective assay for examining the carboxylic acid substrate specificity of NIS synthetases. Application of the assay to the type B NIS synthetase AcsA shows that it is selective for alpha-ketoglutaric acid, confirming a bioinformatics-based prediction of the substrate specificity of this enzyme.
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Affiliation(s)
- Nadia Kadi
- Department of Chemistry, University of Warwick, Coventry, United Kingdom
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Koppisch AT, Hotta K, Fox DT, Ruggiero CE, Kim CY, Sanchez T, Iyer S, Browder CC, Unkefer PJ, Unkefer CJ. Biosynthesis of the 3,4-Dihydroxybenzoate Moieties of Petrobactin by Bacillus anthracis. J Org Chem 2008; 73:5759-65. [DOI: 10.1021/jo800427f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Andrew T. Koppisch
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Kinya Hotta
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - David T. Fox
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Christy E. Ruggiero
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Chu-Young Kim
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Timothy Sanchez
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Srinivas Iyer
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Cindy C. Browder
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Pat J. Unkefer
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
| | - Clifford J. Unkefer
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Departments of Chemistry and Biology, Northern Arizona University, Flagstaff, Arizona 86011, and Department of Biological Science, Faculty of Science, National University of Singapore, Singapore 117543
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Abergel RJ, Zawadzka AM, Raymond KN. Petrobactin-Mediated Iron Transport in Pathogenic Bacteria: Coordination Chemistry of an Unusual 3,4-Catecholate/Citrate Siderophore. J Am Chem Soc 2008; 130:2124-5. [DOI: 10.1021/ja077202g] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rebecca J. Abergel
- Department of Chemistry, University of California, Berkeley, California 94720-1460
| | - Anna M. Zawadzka
- Department of Chemistry, University of California, Berkeley, California 94720-1460
| | - Kenneth N. Raymond
- Department of Chemistry, University of California, Berkeley, California 94720-1460
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33
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A new method for determining positions of phenolic hydroxyl groups through silylation and application of H(Si)C triple-resonance NMR experiments. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.08.111] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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34
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Rodriguez GM, Gardner R, Kaur N, Phanstiel O. Utilization of Fe3+-acinetoferrin analogs as an iron source by Mycobacterium tuberculosis. Biometals 2007; 21:93-103. [PMID: 17401548 DOI: 10.1007/s10534-007-9096-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Accepted: 03/05/2007] [Indexed: 10/23/2022]
Abstract
Mycobacterium tuberculosis, the causative agent of human tuberculosis, synthesizes and secretes siderophores in order to compete for iron (an essential micronutrient). Successful iron acquisition allows M. tuberculosis to survive and proliferate under the iron-deficient conditions encountered in the host. To examine structural determinants important for iron siderophore transport in this pathogen, the citrate-based siderophores petrobactin, acinetoferrin and various acinetoferrin homologs were synthesized and used as iron transport probes. Mutant strains of M. tuberculosis deficient in native siderophore synthesis or transport were utilized to better understand the mechanisms involved in iron delivery via the synthetic siderophores. Acinetoferrin and its derivatives, especially those containing a cyclic imide group, were able to deliver iron or gallium into M. tuberculosis which promoted or inhibited, respectively, the growth of this pathogen.
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Affiliation(s)
- G Marcela Rodriguez
- The Public Health Research Institute at the International Center for Public Health, University of Medicine and Dentistry of New Jersey, 225 Warren Street, Newark, NJ 07103-3535, USA.
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35
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Lee JY, Janes BK, Passalacqua KD, Pfleger BF, Bergman NH, Liu H, Håkansson K, Somu RV, Aldrich CC, Cendrowski S, Hanna PC, Sherman DH. Biosynthetic analysis of the petrobactin siderophore pathway from Bacillus anthracis. J Bacteriol 2007; 189:1698-710. [PMID: 17189355 PMCID: PMC1855748 DOI: 10.1128/jb.01526-06] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Accepted: 12/14/2006] [Indexed: 12/21/2022] Open
Abstract
The asbABCDEF gene cluster from Bacillus anthracis is responsible for biosynthesis of petrobactin, a catecholate siderophore that functions in both iron acquisition and virulence in a murine model of anthrax. We initiated studies to determine the biosynthetic details of petrobactin assembly based on mutational analysis of the asb operon, identification of accumulated intermediates, and addition of exogenous siderophores to asb mutant strains. As a starting point, in-frame deletions of each of the genes in the asb locus (asbABCDEF) were constructed. The individual mutations resulted in complete abrogation of petrobactin biosynthesis when strains were grown on iron-depleted medium. However, in vitro analysis showed that each asb mutant grew to a very limited extent as vegetative cells in iron-depleted medium. In contrast, none of the B. anthracis asb mutant strains were able to outgrow from spores under the same culture conditions. Provision of exogenous petrobactin was able to rescue the growth defect in each asb mutant strain. Taken together, these data provide compelling evidence that AsbA performs the penultimate step in the biosynthesis of petrobactin, involving condensation of 3,4-dihydroxybenzoyl spermidine with citrate to form 3,4-dihydroxybenzoyl spermidinyl citrate. As a final step, the data reveal that AsbB catalyzes condensation of a second molecule of 3,4-dihydroxybenzoyl spermidine with 3,4-dihydroxybenzoyl spermidinyl citrate to form the mature siderophore. This work sets the stage for detailed biochemical studies with this unique acyl carrier protein-dependent, nonribosomal peptide synthetase-independent biosynthetic system.
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Affiliation(s)
- Jung Yeop Lee
- Life Sciences Institute, Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109-2216, USA
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Abergel RJ, Wilson MK, Arceneaux JEL, Hoette TM, Strong RK, Byers BR, Raymond KN. Anthrax pathogen evades the mammalian immune system through stealth siderophore production. Proc Natl Acad Sci U S A 2006; 103:18499-503. [PMID: 17132740 PMCID: PMC1693691 DOI: 10.1073/pnas.0607055103] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Systemic anthrax, caused by inhalation or ingestion of Bacillus anthracis spores, is characterized by rapid microbial growth stages that require iron. Tightly bound and highly regulated in a mammalian host, iron is scarce during an infection. To scavenge iron from its environment, B. anthracis synthesizes by independent pathways two small molecules, the siderophores bacillibactin (BB) and petrobactin (PB). Despite the great efficiency of BB at chelating iron, PB may be the only siderophore necessary to ensure full virulence of the pathogen. In the present work, we show that BB is specifically bound by siderocalin, a recently discovered innate immune protein that is part of an antibacterial iron-depletion defense. In contrast, neither PB nor its ferric complex is bound by siderocalin. Although BB incorporates the common 2,3-dihydroxybenzoyl iron-chelating subunit, PB is novel in that it incorporates the very unusual 3,4-dihydroxybenzoyl chelating subunit. This structural variation results in a large change in the shape of both the iron complex and the free siderophore that precludes siderocalin binding, a stealthy evasion of the immune system. Our results indicate that the blockade of bacterial siderophore-mediated iron acquisition by siderocalin is not restricted to enteric pathogenic organisms and may be a general defense mechanism against several different bacterial species. Significantly, to evade this innate immune response, B. anthracis produces PB, which plays a key role in virulence of the organism. This analysis argues for antianthrax strategies targeting siderophore synthesis and uptake.
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Affiliation(s)
- Rebecca J. Abergel
- *Department of Chemistry, University of California, Berkeley, CA 94720-1460
| | - Melissa K. Wilson
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS 39216-4505; and
| | - Jean E. L. Arceneaux
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS 39216-4505; and
| | - Trisha M. Hoette
- *Department of Chemistry, University of California, Berkeley, CA 94720-1460
| | - Roland K. Strong
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - B. Rowe Byers
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS 39216-4505; and
| | - Kenneth N. Raymond
- *Department of Chemistry, University of California, Berkeley, CA 94720-1460
- To whom correspondence should be addressed. E-mail:
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Zhou Z, Magriotis PA. A new method for the functionalization of [60] fullerene: an unusual 1,3-dipolar cycloaddition pathway leading to a C60 housane derivative. Org Lett 2006; 7:5849-51. [PMID: 16354082 DOI: 10.1021/ol052393i] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
[reaction: see text] A variant of the Huisgen 1,3-dipolar cycloaddition reaction provides a new and convenient functionalization of fullerenes. This method complements the widely used Prato and Bingel-Hirsch reactions. The derived, highly functionalized cyclopentenone and cyclopentenamine fullerene compounds upon hydrolysis are suitable for further functionalization and may serve well in the synthesis of new C60 derivatives possessing uncommon and interesting properties.
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Affiliation(s)
- Zhiguo Zhou
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, USA
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39
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Wilson MK, Abergel RJ, Raymond KN, Arceneaux JEL, Byers BR. Siderophores of Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis. Biochem Biophys Res Commun 2006; 348:320-5. [PMID: 16875672 DOI: 10.1016/j.bbrc.2006.07.055] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Accepted: 07/13/2006] [Indexed: 11/19/2022]
Abstract
Three Bacillus anthracis Sterne strains (USAMRIID, 7702, and 34F2) and Bacillus cereus ATCC 14579 excrete two catecholate siderophores, petrobactin (which contains 3,4-dihydroxybenzoyl moieties) and bacillibactin (which contains 2,3-dihydroxybenzoyl moieties). However, the insecticidal organism Bacillus thuringiensis ATCC 33679 makes only bacillibactin. Analyses of siderophore production by previously isolated [Cendrowski et al., Mol. Microbiol. 52 (2004) 407-417] B. anthracis mutant strains revealed that the B. anthracis bacACEBF operon codes for bacillibactin production and the asbAB gene region is required for petrobactin assembly. The two catecholate moieties also were synthesized by separate routes. PCR amplification identified both asbA and asbB genes in the petrobactin producing strains whereas B. thuringiensis ATCC 33679 retained only asbA. Petrobactin synthesis is not limited to the cluster of B. anthracis strains within the B. cereus sensu lato group (in which B. cereus, B. anthracis, and B. thuringiensis are classified), although petrobactin might be prevalent in strains with pathogenic potential for vertebrates.
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Affiliation(s)
- Melissa K Wilson
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS 39216-4505, USA
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Martin JD, Ito Y, Homann VV, Haygood MG, Butler A. Structure and membrane affinity of new amphiphilic siderophores produced by Ochrobactrum sp. SP18. J Biol Inorg Chem 2006; 11:633-41. [PMID: 16791646 DOI: 10.1007/s00775-006-0112-y] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Accepted: 04/18/2006] [Indexed: 10/24/2022]
Abstract
The coastal alpha-proteobacterium Ochrobactrum sp. SP18 produces a suite of three citrate-derived, cell-associated amphiphilic siderophores, ochrobactins A-C. The ochrobactins are composed of a citric acid backbone amide-linked to two lysine residues. Each epsilon-amine of lysine is hydroxylated and acylated forming two hydroxamic acid moieties. One of the acylated appendages of each ochrobactin is (E)-2-decenoic acid. The other acylated appendages for ochrobactins A-C are (E)-2-octenoic acid, octanoic acid and (E)-2-decenoic acid, respectively. The ferric ochrobactin complexes are photoreactive in UV light, producing an oxidized ligand with loss of 46 mass units that can still coordinate Fe(III). The relative partitioning of the apo-ochrobactins, Fe(III) ochrobactins and Fe(III) photoproducts into 1,2-dimyristoyl-sn-glycero-3-phosphocholine vesicles is presented. The ochrobactins are the first example of aerobactin-based siderophores with two fatty acid appendages produced in a suite with varying acyl appendage lengths.
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Affiliation(s)
- Jessica D Martin
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
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Koppisch AT, Browder CC, Moe AL, Shelley JT, Kinkel BA, Hersman LE, Iyer S, Ruggiero CE. Petrobactin is the primary siderophore synthesized by Bacillus anthracis str. Sterne under conditions of iron starvation. Biometals 2006; 18:577-85. [PMID: 16388397 DOI: 10.1007/s10534-005-1782-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Accepted: 08/08/2005] [Indexed: 11/28/2022]
Abstract
The siderophores of Bacillus anthracis are critical for the pathogen's proliferation and may be necessary for its virulence. Bacillus anthracis str. Sterne cells were cultured in iron free media and the siderophores produced were isolated and purified using a combination of XAD-2 resin, reverse-phase FPLC, and size exclusion chromatography. A combination of 1H and 13C NMR spectroscopy, UV spectroscopy and ESI-MS/MS fragmentation were used to identify the primary siderophore as petrobactin, a catecholate species containing unusual 3,4-dihydroxybenzoate moieties, previously only identified in extracts of Marinobacter hydrocarbonoclasticus. A secondary siderophore was observed and structural analysis of this species is consistent with that reported for bacillibactin, a siderophore observed in many species of bacilli. This is the first structural characterization of a siderophore from B. anthracis, as well as the first characterization of a 3,4-DHB containing catecholate in a pathogen.
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Affiliation(s)
- Andrew T Koppisch
- Bioscience Division, B-4, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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42
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Abstract
Iron is essential for the growth of nearly all microorganisms yet iron is only sparingly soluble near the neutral pH, aerobic conditions in which many microorganisms grow. The pH of ocean water is even higher, thereby further lowering the concentration of dissolved ferric ion. To compound the problem of availability, the total iron concentration is surprisingly low in surface ocean water, yet nevertheless, marine microorganisms still require iron for growth. Like terrestrial bacterial, bacteria isolated from open ocean water often produce siderophores, which are low molecular weight chelating ligands that facilitate the microbial acquisition of iron. The present review summarizes the structures of siderophores produced by marine bacteria and the emerging characteristics that distinguish marine siderophores.
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Affiliation(s)
- Alison Butler
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93111-9510, USA.
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43
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Abstract
This review covers the literature published in 2004 for marine natural products, with 693 citations (491 for the period January to December 2004) referring to compounds isolated from marine microorganisms and phytoplankton, green algae, brown algae, red algae, sponges, coelenterates, bryozoans, molluscs, tunicates and echinoderms. The emphasis is on new compounds (716 for 2004), together with their relevant biological activities, source organisms and country of origin. Biosynthetic studies (8), and syntheses (80), including those that lead to the revision of structures or stereochemistries, have been included.
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Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
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44
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Abstract
Iron is a limiting nutrient for primary production in marine systems, and photochemical processes play a significant role in the upper ocean biogeochemical cycling of this key element. In recent years, progress has been made toward understanding the role of biologically produced organic ligands in controlling the speciation and photochemical redox cycling of iron in ocean surface waters. Most (>99%) of the dissolved iron in seawater is now known to be associated with strong organic ligands. New data concerning the structure and photochemical reactivity of strong Fe(III) binding ligands (siderophores) produced by pelagic marine bacteria suggest that direct photolysis via ligand-to-metal charge transfer reactions may be an important mechanism for the production of reduced, biologically available iron (Fe[II]) in surface waters. Questions remain, however, about the importance of these processes relative to secondary photochemical reactions with photochemically produced radical species, such as superoxide (O2-). The mechanism of superoxide-mediated reduction of Fe(III) in the presence of strong Fe(III) organic ligands is also open to debate. This review highlights recent findings, including both model ligand studies and experimentallobservational studies of the natural seawater ligand pool.
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Affiliation(s)
- Katherine Barbeau
- Geosciences Research Division, Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA, USA.
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45
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Kalinowski DS, Richardson DR. The Evolution of Iron Chelators for the Treatment of Iron Overload Disease and Cancer. Pharmacol Rev 2005; 57:547-83. [PMID: 16382108 DOI: 10.1124/pr.57.4.2] [Citation(s) in RCA: 554] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The evolution of iron chelators from a range of primordial siderophores and aromatic heterocyclic ligands has lead to the formation of a new generation of potent and efficient iron chelators. For example, various siderophore analogs and synthetic ligands, including ICL670A [4-[3,5-bis-(hydroxyphenyl)-1,2,4-triazol-1-yl]-benzoic acid], 4'-hydroxydesazadesferrithiocin, and Triapine, have been developed from predecessors and illustrate potent iron-mobilizing or antineoplastic activities. This review focuses on the evolution of iron chelators from initial lead compounds through to the development of novel chelating agents, many of which show great potential to be clinically applied in the treatment of iron overload disease and cancer.
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Affiliation(s)
- Danuta S Kalinowski
- The Iron Metabolism and Chelation Program, Children's Cancer Institute Australia for Medical Research, Sydney, New South Wales, Australia
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46
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Holt PD, Reid RR, Lewis BL, Luther GW, Butler A. Iron(III) Coordination Chemistry of Alterobactin A: A Siderophore from the Marine Bacterium Alteromonas luteoviolacea. Inorg Chem 2005; 44:7671-7. [PMID: 16212394 DOI: 10.1021/ic0512072] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alterobactin A is a siderophore produced by the oceanic bacterium Alteromonas luteoviolacea. The thermodynamic stability constant of the ferric alterobactin A (Alt-A) complex was estimated from electrochemical measurements on the basis of a previously reported linear relationship between the reduction potentials and the pH-independent stability constants for known iron(III) complexes. The reduction potential of the ferric alterobactin A complex determined by square wave voltammetry is -0.972 V vs SCE and reversible, corresponding to a thermodynamic stability constant of 10(51+/-2). Potentiometric titration of Fe(III)-Alt-A shows the release of six protons on complexation of Fe(III) to Alt-A. The 1H NMR resonances of the Ga(III)-Alt-A complex show that the C-4, C-5, and C-6 catecholate protons and the C(alpha) and C(beta) protons of both beta-hydroxyaspartate moieties are shifted downfield relative to the free ligand, which along with the potentiometric titration data is consistent with a complex in which Fe(III) is coordinated by both catecholate oxygen atoms and both oxygen atoms of each beta-hydroxyaspartate. The UV-vis spectrum of Fe(III)-Alt-A is invariant over the pH range 4-9, indicating the coordination does not change over a wide pH range. In addition, in the absence of a coordinated metal ion, the serine ester of Alt-A hydrolyzes forming Alt-B.
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Affiliation(s)
- Pamela D Holt
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, USA
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47
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Fadeev EA, Luo M, Groves JT. Synthesis and structural modeling of the amphiphilic siderophore rhizobactin-1021 and its analogs. Bioorg Med Chem Lett 2005; 15:3771-4. [PMID: 15990296 DOI: 10.1016/j.bmcl.2005.05.114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2005] [Revised: 05/13/2005] [Accepted: 05/16/2005] [Indexed: 11/22/2022]
Abstract
We describe two convenient syntheses of rhizobactin-1021 (Rz), a citrate-based siderophore amphiphile produced by the nitrogen-fixing root symbiont Rhizobium meliloti-1021, and several analogs. Our approach features a singly amidated, tert-butyl-protected citrate intermediate that easily affords a variety of Rz analogs in the late stages of the synthesis. Structural modeling and the monolayer behavior of Rz and its metal complexes are consistent with a structural reorganization upon Rz-mediated iron chelation.
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Affiliation(s)
- Evgeny A Fadeev
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
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Fadeev EA, Luo M, Groves JT. Synthesis, structure, and molecular dynamics of gallium complexes of schizokinen and the amphiphilic siderophore acinetoferrin. J Am Chem Soc 2005; 126:12065-75. [PMID: 15382941 DOI: 10.1021/ja048145j] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new general synthesis of the citrate-based siderophores acinetoferrin (Af) and schizokinen (Sz) and their analogues is described. The molecular structure of gallium schizokinen, GaSz, was determined by combined (1)H NMR, Hartree-Fock ab initio calculations, DFT, and empirical modeling of vicinal proton NMR spin-spin couplings. The metal-coordination geometry of GaSz was determined from NOE contacts to be cis-cis with respect to the two chelating hydroxamates. One diaminopropane adopts a single chairlike conformation while another is a mixture of two ring pucker arrangements. Both amide hydrogens are internally hydrogen bonded to metal-ligating oxygen atoms. The acyl methyl groups are directed away from each other with an average planar angle of ca. 130 degrees. The kinetics of GaSz racemization were followed by selective, double spin-echo inversion-recovery (1)H NMR spectroscopy over the temperature range of 10-45 degrees C. The racemization proceeds by a multistep mechanism that is proton independent between pD 5 and 12 (k(0) = 1.47 (0.15 s(-1))) and acid catalyzed below pD 4 (k(1) = 2.25 (0.15) x 10(4) M(-1) s(-1)). The activation parameters found for the two sequential steps of the proton independent pathway were DeltaH(++) = 25 +/- 3 kcal M(-1), DeltaS(++) = 25 +/- 7 cal M(-1) K(-1) and DeltaH(++) = 17.1 +/- 0.2 kcal M(-1), DeltaS(++) = 0.3 +/- 2.7 cal M(-1) K(-1). The first step of the proton-independent mechanism was assigned to the dissociation of the carboxyl group. The second step was assigned to complex racemization. The proton-assisted step was assigned to a complete dissociation of the alpha-hydroxy carboxyl group at pD < 4. The ab initio modeling of gallium acinetoferrin, GaAf, and analogues derived from the structure of GaSz has shown that the pendant trans-octenoyl fragments are oriented in opposite directions with the average planar angle of ca. 130 degrees. This arrangement prevents GaAf from adopting a phospholipid-like structural motif. Significantly, iron siderophore complex FeAf was found to be disruptive to phospholipid vesicles and is considerably more hydrophilic than Af, with an eight-fold smaller partition coefficient.
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Affiliation(s)
- Evgeny A Fadeev
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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49
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Luo M, Fadeev EA, Groves JT. Membrane Dynamics of the Amphiphilic Siderophore, Acinetoferrin. J Am Chem Soc 2005; 127:1726-36. [PMID: 15701007 DOI: 10.1021/ja044230f] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acinetobacter haemolyticus is an antibiotic resistant, pathogenic bacterium responsible for an increasing number of hospital infections. Acinetoferrin (Af), the amphiphilic siderophore isolated from this organism, contains two unusual trans-2-octenoyl hydrocarbon chains reminiscent of a phospholipid structural motif. Here, we have investigated the membrane affinity of Af and its iron complex, Fe-Af, using small and large unilamellar phospholipid vesicles (SUV and LUV) as model membranes. Af shows a high membrane affinity with a partition coefficient, K(x)= 6.8 x 10(5). Membrane partitioning and trans-membrane flip-flop of Fe-Af have also been studied via fluorescence quenching of specifically labeled vesicle leaflets and (1)H NMR line-broadening techniques. Fe-Af is found to rapidly redistribute between lipid and aqueous phases with dissociation/partitioning rates of k(off) = 29 s(-1) and k(on) = 2.4 x 10(4) M(-1) s(-1), respectively. Upon binding iron, the membrane affinity of Af is reduced 30-fold to K'(x) = 2.2 x 10(4) for Fe-Af. In addition, trans-membrane flip-flop of Fe-Af occurs with a rate constant, k(p) = 1.2 x 10(-3) s(-1), with egg-PC LUV and a half-life time around 10 min with DMPC SUV. These properties are due to the phospholipid-like conformation of Af and the more extended conformation of Fe-Af that is enforced by iron binding. Remarkable similarities and differences between Af and another amphiphilic siderophore, marinobactin E, are discussed. The potential biological implications of Af and Fe-Af are also addressed. Our approaches using inner- and outer-leaflet-labeled fluorescent vesicles and (1)H NMR line-broadening techniques to discern Af-mediated membrane partitioning and trans-membrane diffusion are amenable to similar studies for other paramagnetic amphiphiles.
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Affiliation(s)
- Minkui Luo
- Department of Chemistry, Princeton University, Princeton, NJ 08540, USA
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50
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Abstract
This review covers the literature published in 2003 for marine natural products, with 619 citations (413 for the period January to December 2003) referring to compounds isolated from marine microorganisms and phytoplankton, green algae, brown algae, red algae, sponges, coelenterates, bryozoans, molluscs, tunicates and echinoderms. The emphasis is on new compounds (656 for 2003), together with their relevant biological activities, source organisms and country or origin. Biosynthetic studies or syntheses that lead to the revision of structures or stereochemistries have been included (78), including any first total syntheses of a marine natural product.
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Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
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