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Alvin L. Crumbliss

University Distinguished Service Professor Emeritus
Chemistry
2104 French Family Science Center, Box 90346, Durham, NC 27708-0354
2104 French Family Science Center, Box 90346, Durham, NC 27708-0354

Selected Publications


A perspective essay on the use of Ga3+ as a proxy for Fe3+ in bioinorganic model studies and its successful use for therapeutic purposes.

Journal Article Journal of inorganic biochemistry · June 2021 The use of Ga3+ as a structural mimic for Fe3+ in model bioinorganic investigations is usually based on a common assumption that Ga3+ and Fe3+ should form bioligand complexes of similar stabilities due to their s ... Full text Cite

Diacetyl exposure disrupts iron homeostasis in animals and cells.

Journal Article Inhal Toxicol · 2021 OBJECTIVE: Several mechanisms have been proposed for the biological effect of diacetyl. We tested the postulate that animal and cell exposures to diacetyl are associated with a disruption in iron homeostasis. MATERIALS AND METHODS: Male, Sprague-Dawley rat ... Full text Link to item Cite

Supramolecular and Liquid Crystalline Contributions to the Assembly of Myofibril.

Journal Article Molecules (Basel, Switzerland) · February 2020 We compare steps observed during the fibrillogenesis of myofibrils with the sequence of steps predictable by a recent analysis of the structurization and functioning of striated muscles. The predicted assembly steps are based solely on fundamental equilibr ... Full text Cite

A Supramolecular Polymerization Approach to the Growth of the Myofibril.

Journal Article Frontiers in chemistry · January 2019 Extended linear structures self-assemble by the multi-stage-open-association mechanism of supramolecular polymerization (MSOA). Application of the model requires the identification of a repeating unit, the main-chain supramolecular bond, and the binding co ... Full text Cite

The kinetics of dimethylhydroxypyridinone interactions with iron(iii) and the catalysis of iron(iii) ligand exchange reactions: implications for bacterial iron transport and combination chelation therapies.

Journal Article Dalton transactions (Cambridge, England : 2003) · May 2018 Many microbes acquire environmental Fe by secreting organic chelators, siderophores, which possess the characteristics of a high and specific binding affinity for iron(iii) that results in the formation of thermodynamically stable, and kinetically inert ir ... Full text Cite

The Assembling and Contraction Mechanisms of Striated Muscles.

Journal Article Frontiers in chemistry · January 2018 A novel approach to the description of the assembly mechanism of functional biological structures is presented. The approach is based on the identification of fundamental self-assembling processes to which an additional structurization "engineered" by Natu ... Full text Cite

Engineering oxidative stability in human hemoglobin based on the Hb providence (βK82D) mutation and genetic cross-linking.

Journal Article The Biochemical journal · December 2017 Previous work suggested that hemoglobin (Hb) tetramer formation slows autoxidation and hemin loss and that the naturally occurring mutant, Hb Providence (HbProv; βK82D), is much more resistant to degradation by H2O2 We have examined s ... Full text Cite

Aqueous solution equilibrium and kinetic studies of iron siderophore and model siderophore complexes

Chapter · January 1, 2017 The emphasis in this review is on chemical studies which are relevant to siderophore-mediated iron uptake by microorganisms. Since almost all chelators which have been established to function as siderophores contain either the hydroxamate (I) or catecholat ... Full text Cite

Amperometric glucose sensor fabricated from glucose oxidase and a mediator coimmobilized on a colloidal gold hydrogel electrode

Conference · January 1, 2017 An amperometric sensor capable of detecting glucose without the addition of exogeneous reagents has application in the hospital, laboratory, and home health care markets. There has been significant recent activity in the development of glucose oxidase (GOD ... Full text Cite

Ferrous iron content of intravenous iron formulations.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · June 2016 The observed biological differences in safety and efficacy of intravenous (IV) iron formulations are attributable to physicochemical differences. In addition to differences in carbohydrate shell, polarographic signatures due to ferric iron [Fe(III)] and fe ... Full text Cite

Preface. Biometals 2014--Proceedings of the 9th International Symposium Biometals 2014 at Duke University, Durham, NC, USA.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · June 2015 Full text Cite

Bordetella pertussis FbpA binds both unchelated iron and iron siderophore complexes.

Journal Article Biochemistry · June 2014 Bordetella pertussis is the causative agent of whooping cough. This pathogenic bacterium can obtain the essential nutrient iron using its native alcaligin siderophore and by utilizing xeno-siderophores such as desferrioxamine B, ferrichrome, and enterobact ... Full text Cite

Redox properties of human hemoglobin in complex with fractionated dimeric and polymeric human haptoglobin.

Journal Article Free radical biology & medicine · April 2014 Haptoglobin (Hp) is an abundant and conserved plasma glycoprotein, which binds acellular adult hemoglobin (Hb) dimers with high affinity and facilitates their rapid clearance from circulation after hemolysis. Humans possess three main phenotypes of Hp, des ... Full text Cite

Surface-bound iron: a metal ion buffer in the marine brown alga Ectocarpus siliculosus?

Journal Article Journal of experimental botany · February 2014 Although the iron uptake and storage mechanisms of terrestrial/higher plants have been well studied, the corresponding systems in marine algae have received far less attention. Studies have shown that while some species of unicellular algae utilize unique ... Full text Cite

Borate as a synergistic anion for Marinobacter algicola ferric binding protein, FbpA: a role for boron in iron transport in marine life.

Journal Article Journal of the American Chemical Society · October 2013 Boron in the ocean is generally considered a nonbiological element due to its relatively high concentration (0.4 mM) and depth independent concentration profile. Here we report an unexpected role for boron in the iron transport system of the marine bacteri ... Full text Cite

Oxygen binding to partially nitrosylated hemoglobin.

Journal Article Biochimica et biophysica acta · September 2013 Reactions of nitric oxide (NO) with hemoglobin (Hb) are important elements in protection against nitrosative damage. NO in the vasculature is depleted by the oxidative reaction with oxy Hb or by binding to deoxy Hb to generate partially nitrosylated Hb (Hb ... Full text Cite

Regulation of iron transport related genes by boron in the marine bacterium Marinobacter algicola DG893.

Journal Article Metallomics : integrated biometal science · August 2013 While there has been extensive interest in the use of boron isotope ratios as a surrogate of pH in paleoclimate studies in the context of climate change-related questions, the high (0.4 mM) concentration and the depth-independent (conservative or non-nutri ... Full text Cite

Molecular controls of the oxygenation and redox reactions of hemoglobin.

Journal Article Antioxidants & redox signaling · June 2013 SignificanceThe broad classes of O(2)-binding proteins known as hemoglobins (Hbs) carry out oxygenation and redox functions that allow organisms with significantly different physiological demands to exist in a wide range of environments. This is a ... Full text Cite

α-Hemoglobin stabilizing protein (AHSP) markedly decreases the redox potential and reactivity of α-subunits of human HbA with hydrogen peroxide.

Journal Article The Journal of biological chemistry · February 2013 α-Hemoglobin stabilizing protein (AHSP) is a molecular chaperone that binds monomeric α-subunits of human hemoglobin A (HbA) and modulates heme iron oxidation and subunit folding states. Although AHSP·αHb complexes autoxidize more rapidly than HbA, the red ... Full text Cite

A perspective essay on the use of Ga3+ as a proxy for Fe3+ in bioinorganic model studies and its successful use for therapeutic purposes.

Journal Article Journal of inorganic biochemistry · June 2021 The use of Ga3+ as a structural mimic for Fe3+ in model bioinorganic investigations is usually based on a common assumption that Ga3+ and Fe3+ should form bioligand complexes of similar stabilities due to their s ... Full text Cite

Diacetyl exposure disrupts iron homeostasis in animals and cells.

Journal Article Inhal Toxicol · 2021 OBJECTIVE: Several mechanisms have been proposed for the biological effect of diacetyl. We tested the postulate that animal and cell exposures to diacetyl are associated with a disruption in iron homeostasis. MATERIALS AND METHODS: Male, Sprague-Dawley rat ... Full text Link to item Cite

Supramolecular and Liquid Crystalline Contributions to the Assembly of Myofibril.

Journal Article Molecules (Basel, Switzerland) · February 2020 We compare steps observed during the fibrillogenesis of myofibrils with the sequence of steps predictable by a recent analysis of the structurization and functioning of striated muscles. The predicted assembly steps are based solely on fundamental equilibr ... Full text Cite

A Supramolecular Polymerization Approach to the Growth of the Myofibril.

Journal Article Frontiers in chemistry · January 2019 Extended linear structures self-assemble by the multi-stage-open-association mechanism of supramolecular polymerization (MSOA). Application of the model requires the identification of a repeating unit, the main-chain supramolecular bond, and the binding co ... Full text Cite

The kinetics of dimethylhydroxypyridinone interactions with iron(iii) and the catalysis of iron(iii) ligand exchange reactions: implications for bacterial iron transport and combination chelation therapies.

Journal Article Dalton transactions (Cambridge, England : 2003) · May 2018 Many microbes acquire environmental Fe by secreting organic chelators, siderophores, which possess the characteristics of a high and specific binding affinity for iron(iii) that results in the formation of thermodynamically stable, and kinetically inert ir ... Full text Cite

The Assembling and Contraction Mechanisms of Striated Muscles.

Journal Article Frontiers in chemistry · January 2018 A novel approach to the description of the assembly mechanism of functional biological structures is presented. The approach is based on the identification of fundamental self-assembling processes to which an additional structurization "engineered" by Natu ... Full text Cite

Engineering oxidative stability in human hemoglobin based on the Hb providence (βK82D) mutation and genetic cross-linking.

Journal Article The Biochemical journal · December 2017 Previous work suggested that hemoglobin (Hb) tetramer formation slows autoxidation and hemin loss and that the naturally occurring mutant, Hb Providence (HbProv; βK82D), is much more resistant to degradation by H2O2 We have examined s ... Full text Cite

Aqueous solution equilibrium and kinetic studies of iron siderophore and model siderophore complexes

Chapter · January 1, 2017 The emphasis in this review is on chemical studies which are relevant to siderophore-mediated iron uptake by microorganisms. Since almost all chelators which have been established to function as siderophores contain either the hydroxamate (I) or catecholat ... Full text Cite

Amperometric glucose sensor fabricated from glucose oxidase and a mediator coimmobilized on a colloidal gold hydrogel electrode

Conference · January 1, 2017 An amperometric sensor capable of detecting glucose without the addition of exogeneous reagents has application in the hospital, laboratory, and home health care markets. There has been significant recent activity in the development of glucose oxidase (GOD ... Full text Cite

Ferrous iron content of intravenous iron formulations.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · June 2016 The observed biological differences in safety and efficacy of intravenous (IV) iron formulations are attributable to physicochemical differences. In addition to differences in carbohydrate shell, polarographic signatures due to ferric iron [Fe(III)] and fe ... Full text Cite

Preface. Biometals 2014--Proceedings of the 9th International Symposium Biometals 2014 at Duke University, Durham, NC, USA.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · June 2015 Full text Cite

Bordetella pertussis FbpA binds both unchelated iron and iron siderophore complexes.

Journal Article Biochemistry · June 2014 Bordetella pertussis is the causative agent of whooping cough. This pathogenic bacterium can obtain the essential nutrient iron using its native alcaligin siderophore and by utilizing xeno-siderophores such as desferrioxamine B, ferrichrome, and enterobact ... Full text Cite

Redox properties of human hemoglobin in complex with fractionated dimeric and polymeric human haptoglobin.

Journal Article Free radical biology & medicine · April 2014 Haptoglobin (Hp) is an abundant and conserved plasma glycoprotein, which binds acellular adult hemoglobin (Hb) dimers with high affinity and facilitates their rapid clearance from circulation after hemolysis. Humans possess three main phenotypes of Hp, des ... Full text Cite

Surface-bound iron: a metal ion buffer in the marine brown alga Ectocarpus siliculosus?

Journal Article Journal of experimental botany · February 2014 Although the iron uptake and storage mechanisms of terrestrial/higher plants have been well studied, the corresponding systems in marine algae have received far less attention. Studies have shown that while some species of unicellular algae utilize unique ... Full text Cite

Borate as a synergistic anion for Marinobacter algicola ferric binding protein, FbpA: a role for boron in iron transport in marine life.

Journal Article Journal of the American Chemical Society · October 2013 Boron in the ocean is generally considered a nonbiological element due to its relatively high concentration (0.4 mM) and depth independent concentration profile. Here we report an unexpected role for boron in the iron transport system of the marine bacteri ... Full text Cite

Oxygen binding to partially nitrosylated hemoglobin.

Journal Article Biochimica et biophysica acta · September 2013 Reactions of nitric oxide (NO) with hemoglobin (Hb) are important elements in protection against nitrosative damage. NO in the vasculature is depleted by the oxidative reaction with oxy Hb or by binding to deoxy Hb to generate partially nitrosylated Hb (Hb ... Full text Cite

Regulation of iron transport related genes by boron in the marine bacterium Marinobacter algicola DG893.

Journal Article Metallomics : integrated biometal science · August 2013 While there has been extensive interest in the use of boron isotope ratios as a surrogate of pH in paleoclimate studies in the context of climate change-related questions, the high (0.4 mM) concentration and the depth-independent (conservative or non-nutri ... Full text Cite

Molecular controls of the oxygenation and redox reactions of hemoglobin.

Journal Article Antioxidants & redox signaling · June 2013 SignificanceThe broad classes of O(2)-binding proteins known as hemoglobins (Hbs) carry out oxygenation and redox functions that allow organisms with significantly different physiological demands to exist in a wide range of environments. This is a ... Full text Cite

α-Hemoglobin stabilizing protein (AHSP) markedly decreases the redox potential and reactivity of α-subunits of human HbA with hydrogen peroxide.

Journal Article The Journal of biological chemistry · February 2013 α-Hemoglobin stabilizing protein (AHSP) is a molecular chaperone that binds monomeric α-subunits of human hemoglobin A (HbA) and modulates heme iron oxidation and subunit folding states. Although AHSP·αHb complexes autoxidize more rapidly than HbA, the red ... Full text Cite

Characterization of the aqueous iron(III) chelation chemistry of a potential Trojan Horse antimicrobial agent: chelate structure, stability and pH dependent speciation.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · October 2012 The aqueous solution equilibria of a β-lactam antimicrobial agent containing a 3-hydroxy, 4-pyridinone group (L (PF)) binding to Fe(III) in aqueous solution has been characterized through spectrophotometric and potentiometric titrat ... Full text Cite

Haptoglobin alters oxygenation and oxidation of hemoglobin and decreases propagation of peroxide-induced oxidative reactions.

Journal Article Free radical biology & medicine · September 2012 We compared oxygenation and anaerobic oxidation reactions of a purified complex of human hemoglobin (Hb) and haptoglobin (Hb-Hp) to those of uncomplexed Hb. Under equilibrium conditions, Hb-Hp exhibited active-site heterogeneity and noncooperative, high-af ... Full text Cite

Amelioration of metal-induced toxicity in Caenorhabditis elegans: utility of chelating agents in the bioremediation of metals.

Journal Article Toxicological sciences : an official journal of the Society of Toxicology · September 2012 The presence of toxic amounts of transition metals in the environment may originate from a range of human activities and natural processes. One method for the removal of toxic levels of metals is through chelation by small molecules. However, chelation is ... Full text Cite

Synthesis and redox characterization of phosphazene terpolymers with pendant ferrocene groups

Journal Article Macromolecules · May 8, 2012 The synthesis, characterization, and electrochemistry of a series of five ferrocene-containing phosphazene terpolymers derived from the poly(alkyl/arylphosphazene) random copolymer, [(Ph)(Me)PN] 0.6[Me 2PN] 0.4, 5, are described. The new terpolymers, 6 {[( ... Full text Cite

Evidence of Fe3+ interaction with the plug domain of the outer membrane transferrin receptor protein of Neisseria gonorrhoeae: implications for Fe transport.

Journal Article Metallomics : integrated biometal science · April 2012 Neisseria gonorrhoeae is an obligate pathogen that hijacks iron from the human iron transport protein, holo-transferrin (Fe(2)-Tf), by expressing TonB-dependent outer membrane receptor proteins, TbpA and TbpB. Homologous to other TonB-dependent outer membr ... Full text Cite

FbpA--a bacterial transferrin with more to offer.

Journal Article Biochimica et biophysica acta · March 2012 BackgroundGram negative bacteria require iron for growth and virulence. It has been shown that certain pathogenic bacteria such as Neisseria gonorrhoeae possess a periplasmic protein called ferric binding protein (FbpA), which is a node in the tra ... Full text Cite

Slow histidine H/D exchange protocol for thermodynamic analysis of protein folding and stability using mass spectrometry.

Journal Article Analytical chemistry · February 2012 Described here is a mass spectrometry-based protocol to study the thermodynamic stability of proteins and protein-ligand complexes using the chemical denaturant dependence of the slow H/D exchange reaction of the imidazole C(2) proton in histidine side cha ... Full text Cite

Iron Transport in Living Cells

Journal Article · January 13, 2012 Full text Cite

Fe(III)-complexes of the tripodal trishydroxamate siderophore basidiochrome: potential biological implications.

Journal Article Journal of inorganic biochemistry · December 2011 One method of mobilization of iron by mycorrhizal organisms is through the secretion of small organic chelators called siderophores. Hydroxamate donor chelators are a common type of siderophore that is frequently used by fungal organisms. The primary sider ... Full text Cite

Steric factors moderate conformational fluidity and contribute to the high proton sensitivity of Root effect hemoglobins.

Journal Article Biochimica et biophysica acta · October 2011 The structural basis of the extreme pH dependence of oxygen binding to Root effect Hbs is a long-standing puzzle in the field of protein chemistry. A previously unappreciated role of steric factors in the Root effect was revealed by a comparison of pH effe ... Full text Cite

Characterization of Fe(III) sequestration by an analog of the cytotoxic siderophore brasilibactin A: implications for the iron transport mechanism in mycobacteria.

Journal Article Metallomics : integrated biometal science · May 2011 Mycobacteria such as M. tuberculosis represent a significant health concern throughout much of the developing world. In mycobacteria and other pathogenic bacteria, an important virulence factor is the ability of the bacterium to obtain iron from its host. ... Full text Cite

Design, synthesis, and study of a mycobactin-artemisinin conjugate that has selective and potent activity against tuberculosis and malaria.

Journal Article Journal of the American Chemical Society · February 2011 Although the antimalarial agent artemisinin itself is not active against tuberculosis, conjugation to a mycobacterial-specific siderophore (microbial iron chelator) analogue induces significant and selective antituberculosis activity, including activity ag ... Full text Cite

Siderophore-redox active ionophore host-guest assemblies: A prototype for selective metal ion compartmentalization

Journal Article Inorganica Chimica Acta · October 25, 2010 The reduction potentials for two Wurster's crowns, aza crown ethers which incorporate the redox active N,N,N′,N′-tetraalkyl-1,4- phenylenediamine into the structure of 18-crown-6, were studied in the presence of the siderophore ferrioxamine B, FeHDFB+. Add ... Full text Cite

Extreme differences between hemoglobins I and II of the clam Lucina pectinalis in their reactions with nitrite.

Journal Article Biochimica et biophysica acta · October 2010 The clam Lucina pectinalis supports its symbiotic bacteria by H₂S transport in the open and accessible heme pocket of Lucina Hb I and by O₂ transport in the narrow and crowded heme pocket of Lucina Hb II. Remarkably, air-equilibrated samples of Lucina Hb I ... Full text Cite

Synthesis and iron sequestration equilibria of novel exocyclic 3-hydroxy-2-pyridinone donor group siderophore mimics.

Journal Article Inorganic chemistry · September 2010 The synthesis of a novel class of exocyclic bis- and tris-3,2-hydroxypyridinone (HOPO) chelators built on N(2) and N(3) aza-macrocyclic scaffolds and the thermodynamic solution characterization of their complexes with Fe(III) are described. The chelators f ... Full text Open Access Cite

Redox potentials of Ti(IV) and Fe(III) complexes provide insights into titanium biodistribution mechanisms.

Journal Article Journal of inorganic biochemistry · September 2010 Transferrin, the human iron transport protein, binds Ti(IV) even more tightly than it binds Fe(III). However, the fate of titanium bound to transferrin is not well understood. Here we present results which address the fate of titanium once bound to transfe ... Full text Cite

Role of citrate and phosphate anions in the mechanism of iron(III) sequestration by ferric binding protein: kinetic studies of the formation of the holoprotein of wild-type FbpA and its engineered mutants.

Journal Article Biochemistry · July 2010 Ferric binding protein A (FbpA) plays a central role in the iron acquisition processes of pathogenic Neisseria gonorrheae, Neisseria meningitidis, and Haemophilus influenzae. FbpA functions as an iron shuttle within the periplasmic space of these Gram-nega ... Full text Open Access Cite

Kinetics and mechanism of exogenous anion exchange in FeFbpA-NTA: significance of periplasmic anion lability and anion binding activity of ferric binding protein A.

Journal Article Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry · February 2010 The bacterial transferrin ferric binding protein A (FbpA) requires an exogenous anion to facilitate iron sequestration, and subsequently to shuttle the metal across the periplasm to the cytoplasmic membrane. In the diverse conditions of the periplasm, nume ... Full text Cite

The redox hypothesis in siderophore-mediated iron uptake.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · August 2009 The viability of iron(III/II) reduction as the initial step in the in vivo release of iron from its thermodynamically stable siderophore complex is explored. ... Full text Cite

Characterization of second coordination shell ionophore-siderophore host-guest assemblies and binding selectivities in binary and complex mixtures by electrospray ionization mass spectrometry

Journal Article Journal of Inclusion Phenomena and Macrocyclic Chemistry · June 1, 2009 An ESI-MS method for the determination of host-guest association constants and binding selectivities for systems of binary and complex mixtures, respectively, is presented in an effort to quantitatively study the strength of host-guest interactions, while ... Full text Cite

Hijacking transferrin bound iron: protein-receptor interactions involved in iron transport in N. gonorrhoeae.

Journal Article Metallomics : integrated biometal science · January 2009 Neisseria gonorrhoeae has the capacity to acquire iron from its human host by removing this essential nutrient from serum transferrin. The transferrin binding proteins, TbpA and TbpB constitute the outer membrane receptor complex responsible for binding tr ... Full text Cite

Ga3+ as a mechanistic probe in Fe3+ transport: characterization of Ga3+ interaction with FbpA.

Journal Article Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry · August 2008 The obligate human pathogens Haemophilus influenzae, Neisseria gonorrhoeae, and N. meningitidis utilize a highly conserved, three-protein ATP-binding cassette transporter (FbpABC) to shuttle free Fe(3+) from the periplasm and across the cytoplasmic membran ... Full text Cite

An investigation of hemopexin redox properties by spectroelectrochemistry: biological relevance for heme uptake.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · June 2008 Hemopexin (HPX) has two principal roles: it sequesters free heme in vivo for the purpose of preventing the toxic effects of this moiety, which is largely due to heme's ability to catalyze free radical formation, and it transports heme intracellularly thus ... Full text Cite

Synthesis, siderophore activity and iron(III) chelation chemistry of a novel mono-hydroxamate, bis-catecholate siderophore mimic: N(alpha),-N(epsilon)-Bis[2,3-dihydroxybenzoyl]-l-lysyl-(gamma-N-methyl-N-hydroxyamido)-L-glutamic acid.

Journal Article Journal of inorganic biochemistry · April 2008 The synthesis and characterization of a novel tripodal mono-hydroxamate, bis catecholate siderophore mimic, N(alpha),-N(epsilon)-bis[2,3-dihydroxybenzoyl]-l-lysyl-(gamma-N-methyl-N-hydroxyamido)-l-glutamic acid (H(6)L), is described. The structure of H(6)L ... Full text Cite

Ex vivo analysis of synergistic anion binding to FbpA in Gram-negative bacteria.

Journal Article Biochemistry · April 2008 Ferric binding protein, FbpA, is a member of the transferrin superfamily whose function is to move an essential nutrient, iron, across the periplasm and into the cytosol through formation of a ternary complex containing Fe (3+) and a synergistic anion, X. ... Full text Cite

Synthesis and biological activity of saccharide based lipophilic siderophore mimetics as potential growth promoters for mycobacteria.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · February 2008 Siderophores based on sugar backbones substituted at the 2,3,4- or 2,3,6 positions with hydroxamic or retro-hydroxamic acid chelating units were synthesized and characterized. The alkyl terminus of the iron-coordinating side chain units facilitate lipophil ... Full text Cite

Iron chelation equilibria, redox, and siderophore activity of a saccharide platform ferrichrome analogue.

Journal Article Inorganic chemistry · October 2007 A complete characterization of the aqueous solution Fe(III) and Fe(II) coordination chemistry of a saccharide-based ferrichrome analogue, 1-O-methyl-2,3,6-tris-O-[4-(N-hydroxy-N-ethylcarbamoyl)-n-butyryl]-alpha-D-glucopyranoside (H3LN236), is reported incl ... Full text Cite

Genetic diversity of coastal bottlenose dolphins revealed by structurally and functionally diverse hemoglobins.

Journal Article Gene · August 15, 2007 Studies of structure-function relationships in the respiratory proteins of marine mammals revealed unexpected variations in the number and types of hemoglobins (Hbs) present in coastal bottlenose dolphins, Tursiops truncatus. We obtained blood samples from ... Full text Link to item Cite

Allosteric effects on oxidative and nitrosative reactions of cell-free hemoglobins.

Journal Article IUBMB life · August 2007 A review of the oxidative and nitrosative reactions of cell-free hemoglobin-based oxygen carriers (HBOCs) shows that these reactions are intimately linked and are subject to allosteric control. Cross-linking reactions used to produce HBOCs introduce confor ... Full text Cite

Sulfate as a synergistic anion facilitating iron binding by the bacterial transferrin FbpA: the origins and effects of anion promiscuity.

Journal Article Journal of the American Chemical Society · August 2007 The ferric binding protein, FbpA, has been demonstrated to facilitate the transport of naked Fe3+ across the periplasmic space of several Gram-negative bacteria. The sequestration of iron by FbpA is facilitated by the presence of a synergistic anion, such ... Full text Cite

The Haemophilus influenzae hFbpABC Fe3+ transporter: analysis of the membrane permease and development of a gallium-based screen for mutants.

Journal Article Journal of bacteriology · July 2007 The obligate human pathogen Haemophilus influenzae utilizes a siderophore-independent (free) Fe(3+) transport system to obtain this essential element from the host iron-binding protein transferrin. The hFbpABC transporter is a binding protein-dependent ABC ... Full text Cite

Environmental factors influence the production of enterobactin, salmochelin, aerobactin, and yersiniabactin in Escherichia coli strain Nissle 1917.

Journal Article International journal of medical microbiology : IJMM · December 2006 The probiotic Escherichia coli strain Nissle 1917 produces four siderophores: the catecholates enterobactin and salmochelin, the hydroxamate aerobactin, and the mixed-type siderophore yersiniabactin. We studied the influence of pH, temperature, and carbon ... Full text Cite

Ternary complex formation facilitates a redox mechanism for iron release from a siderophore.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · April 2006 While the naturally occurring reducing agents glutathione (GSH) and ascorbate (H2A) alone are ineffective at reducing iron(III) sequestered by the siderophore ferrioxamine B, the addition of an iron(II) chelator, sulfonated bathophenanthroline (BPDS), faci ... Full text Cite

An ELF and AIM study of NO2 and N2O4

Journal Article Chemical Physics · August 8, 2005 The B3LYP/cc-pvtz approach is used to obtain Kohn-Sham wavefunctions for NO2 and N2O4 and several related compounds. ELF and AIM analyses on these systems lead to a better understanding of the unusual character of the NN bond in N2O4 in which competing Lew ... Full text Cite

Kinetics of iron release from ferric binding protein (FbpA): mechanistic implications in bacterial periplasm-to-cytosol Fe3+ transport.

Journal Article Biochemistry · July 2005 The ferric binding protein (FbpA) transports iron across the periplasmic space of certain Gram-negative bacteria and is an important component involved in iron acquisition by pathogenic Neisseria spp. (Neisseria gonorrheae and Neisseria meningitidis). Prev ... Full text Cite

Use of phosphorus ligand NMR probes to investigate electronic and second-sphere solvent effects in ligand substitution reactions at manganese(II) and manganese(III).

Journal Article Inorganic chemistry · May 2005 Manganese/ligand association dynamics were studied using a series of structurally related anionic phosphorus ester ligand probes [CH(3)OP(O)(X)(Y)(-), where X = CH(3)O, CH(3)CH(2), or H and Y = O, S, or BH(3)]. Reactions of the probe ions with Mn(H(2)O)(6) ... Full text Cite

Coordination chemistry and redox processes in siderophore-mediated iron transport

Journal Article Geomicrobiology Journal · April 1, 2005 In this mini-review we present an environmental iron mobility/transport scheme consisting of inter-related controls, whereby the first coordination shell of iron modulates the iron redox potential (E1/2), and the oxidation state of iron controls the chemis ... Full text Cite

Critical redox and allosteric aspects of nitric oxide interactions with hemoglobin.

Journal Article Antioxidants & redox signaling · December 2004 Nitric oxide (NO) is an important signaling molecule. Relatively long-lived NO adducts at the heme and SH groups of hemoglobin (Hb) could enable NO to carry out long-range signaling functions. In spite of significant advances, there remain as yet unresolve ... Full text Cite

SUPREX (Stability of Unpurified Proteins from Rates of H/D Exchange) analysis of the thermodynamics of synergistic anion binding by ferric-binding protein (FbpA), a bacterial transferrin.

Journal Article Biochemistry · December 2004 SUPREX (stability of unpurified proteins from rates of H/D exchange) is a H/D exchange- and matrix-assisted laser desorption/ionization (MALDI)-based technique for characterizing the equilibrium unfolding/refolding properties of proteins and protein-ligand ... Full text Cite

Phosphate ester hydrolysis is catalyzed by a bacterial transferrin: potential implications for in vivo iron transport mechanisms.

Journal Article Journal of inorganic biochemistry · November 2004 Two synergistic anions, p-nitrophenyl phosphate ester (NPP) and SO(4)(2-), were found to form new stable assemblies with Fe(3+) and a bacterial transferrin, FbpA (FbpA=ferric binding protein). Fe(3+)FbpA-SO(4) undergoes rapid anion exchange in the presence ... Full text Cite

New insights into the proton-dependent oxygen affinity of Root effect haemoglobins.

Journal Article Acta physiologica Scandinavica · November 2004 A long-standing puzzle with regard to protein structure/function relationships is the proton-dependent modification of haemoglobin (Hb) structure that causes oxygen to be unloaded from Root effect Hbs into the swim bladders and eyes of fish even against hi ... Full text Cite

Iron chelation properties of an extracellular siderophore exochelin MS.

Journal Article Inorganic chemistry · October 2004 The coordination chemistry of an extracellular siderophore produced by Mycobacterium smegmatis, exochelin MS (ExoMS), is reported along with its pK(a) values, Fe(III) and Fe(II) chelation constants, and aqueous solution speciation as determined by spectrop ... Full text Cite

Kinetics and mechanism of axial ligand substitution of alkyl cobaloximes by substituted pyridines in different solvents

Journal Article Chemtracts · October 1, 2004 These researchers demonstrated that the trans-alkyl group in the vitamin B 12 model RCo(dmgH) 2(solvent) affects the rate and nature of the ligand exchange reaction, based on the ability of the alkyl ligand to donate electron density to the Co(III) center. ... Cite

Kinetics and mechanism of iron(III) complexation by ferric binding protein: the role of phosphate.

Journal Article Biochemistry · May 2004 Iron transport across the periplasmic space to the cytoplasmic membrane of certain Gram-negative bacteria is mediated by a ferric binding protein (Fbp). This requires Fe(3+) loading of Fbp at the inner leaflet of the outer membrane. A synergistic anion is ... Full text Cite

Beryllium(II) binding to ATP and ADP: potentiometric determination of the thermodynamic constants and implications for in vivo toxicity.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · April 2004 Highly toxic beryllium(II) is divalent metal ion with a high charge density, making it a potential target for binding to bio-molecules rich in O donor groups. In aqueous solution Be2+ binds to ATP and ADP to form 1:1 Be2+:ATP and Be2+:ADP complexes in rela ... Full text Cite

Redox properties of human transferrin bound to its receptor.

Journal Article Biochemistry · January 2004 Virtually all organisms require iron, and iron-dependent cells of vertebrates (and some more ancient species) depend on the Fe(3+)-binding protein of the circulation, transferrin, to meet their needs. In its iron-donating cycle, transferrin is first captur ... Full text Cite

Crystal and molecular structures of ionophore-siderophore host-guest supramolecular assemblies relevant to molecular recognition.

Journal Article Journal of the American Chemical Society · December 2003 Ionophore-siderophore host-guest assemblies composed of 18-crown-6 and ferrioxamine B, benzo-18-crown-6 and ferrioxamine B, and cis-syn-cis-dicyclohexano-18-crown-6 and ferrioxamine B were successfully crystallized, and their structures were determined by ... Full text Cite

High-Resolution Structure of an Alternate Form of the Ferric Ion Binding Protein from Haemophilus influenzae

Journal Article Chemtracts · November 1, 2003 Even though a closed form of the holo H9Q FbpA mutant was not realized in this study, the X-ray crystallography portrays an interesting open form of FbpA that can bind Fe3+ along with a large chelator molecule (EDTA). The observation that Fe3+ can bind to ... Cite

Kinetics and mechanism of iron release from the bacterial ferric binding protein nFbp: exogenous anion influence and comparison with mammalian transferrin.

Journal Article Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry · November 2003 Ferric binding protein, Fbp, serves an essential biological function in shuttling naked (hydrated) Fe(3+) across the periplasmic space of many Gram-negative bacteria. In this process, iron must be released at the cytoplasmic membrane to a permease. How iro ... Full text Cite

The case of the missing NO-hemoglobin: spectral changes suggestive of heme redox reactions reflect changes in NO-heme geometry.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · October 2003 When low levels of gaseous nitric oxide (NO) are equilibrated with deoxygenated Hb, all NO added can be accounted for in terms of hexacoordinate and pentacoordinate forms of NO-Hb, despite recent reports on NO disappearance from heme groups to form nitroxy ... Full text Cite

Carrier-facilitated bulk liquid membrane transport of iron(iii) hydroxamate complexes utilizing a labile recognition agent and amine recognition in the second coordination sphere

Journal Article Journal of the Chemical Society. Dalton Transactions · September 25, 2003 Carrier-facilitated bulk liquid membrane transport from an aqueous source phase through a chloroform membrane phase to an aqueous receiving phase was studied for various Fe(iii) hydroxamate complexes (siderophore mimics) using second coordination sphere re ... Full text Cite

Carrier-facilitated bulk liquid membrane transport of iron(III)-siderophore complexes utilizing first coordination sphere recognition.

Journal Article Inorganic chemistry · September 2003 Carrier-facilitated bulk liquid membrane (BLM) transport from an aqueous source phase through a chloroform membrane phase to an aqueous receiving phase was studied for various hydrophilic synthetic and naturally occurring Fe(III)-siderophore complexes usin ... Full text Cite

Synthesis and in vitro antioxidant properties of manganese(III) beta-octabromo-meso-tetrakis(4-carboxyphenyl)porphyrin.

Journal Article Journal of inorganic biochemistry · July 2003 Manganese(III) meso-tetrakis(4-carboxypheny)porphyrin (MnTBAP) is a readily available and widely used agent to scavenge reactive oxygen species. A major limitation of MnTBAP is its relatively weak potency due to its low metal centered redox potential. The ... Full text Cite

Kinetics and mechanism of iron(III)-nitrilotriacetate complex reactions with phosphate and acetohydroxamic acid.

Journal Article Inorganic chemistry · June 2003 The kinetics and mechanism of the substitution of coordinated water in nitrilotriacetate complexes of iron(III) (Fe(NTA)(OH(2))(2) and Fe(NTA)(OH(2))(OH)(-)) by phosphate (H(2)PO(4)(-) and HPO(4)(2)(-)) and acetohydroxamic acid (CH(3)C(O)N(OH)H) were inves ... Full text Cite

Iron chelation properties of an extracellular siderophore exochelin MN.

Journal Article Journal of the American Chemical Society · June 2003 The coordination chemistry of an extracellular siderophore produced by Mycobacterium neoaurum, exochelin MN (ExoMN), is reported along with its pK(a) values, Fe(III) and Fe(II) chelation constants, and aqueous solution speciation as determined by spectroph ... Full text Cite

The influence of the synergistic anion on iron chelation by ferric binding protein, a bacterial transferrin.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · April 2003 Although the presence of an exogenous anion is a requirement for tight Fe(3+) binding by the bacterial (Neisseria) transferrin nFbp, the identity of the exogenous anion is not specific in vitro. nFbp was reconstituted as a stable iron containing protein by ... Full text Cite

Fe(III) coordination properties of a new saccharide-based exocyclic trihydroxamate analogue of ferrichrome.

Journal Article Inorganic chemistry · January 2003 The coordination chemistry of a saccharide-based ferrichrome analogue, 1-O-methyl-2,3,4-tris-O-[4-(N-hydroxy-N-methylcarbamoyl)-n-butyrate]-alpha-d-glucopyranoside (H(3)L), is reported, along with its pK(a) values, Fe(III) and Fe(II) chelation constants, a ... Full text Cite

Chemical aspects of siderophore mediated iron transport.

Journal Article Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine · December 2002 In this mini-review we describe selected aspects of the coordination chemistry relevant to siderophore mediated iron transport and bioavailability. Specific emphasis is placed on a discussion of in vitro kinetic and thermodynamic data that are relevant to ... Full text Cite

Heme redox properties of S-nitrosated hemoglobin A0 and hemoglobin S: implications for interactions of nitric oxide with normal and sickle red blood cells.

Journal Article J Biol Chem · April 26, 2002 S-Nitrosated hemoglobin is remarkably stable and can be cycled between deoxy, oxygenated, or oxidized forms without significant loss of NO. Here we show that S-nitrosation of adult human hemoglobin (Hb A(0)) or sickle cell Hb (Hb S) results in an increased ... Full text Link to item Cite

Thermodynamics, kinetics, and mechanism of the stepwise dissociation and formation of Tris(L-lysinehydroxamato)iron(III) in aqueous acid.

Journal Article Inorg Chem · March 25, 2002 pK(a) values for the hydroxamic acid, alpha-NH(3)(+), and epsilon-NH(3)(+) groups of L-lysinehydroxamic acid (LyHA, H(3)L(2+)) were found to be 6.87, 8.89, and 10.76, respectively, in aqueous solution (I = 0.1 M, NaClO(4)) at 25 degrees C. O,O coordination ... Full text Link to item Cite

Fe(III) coordination properties of two new saccharide-based enterobactin analogues: methyl 2,3,4-tris-O-[N-[2,3-di(hydroxy)benzoyl-glycyl]-aminopropyl]-alpha-D-glucopyranoside and methyl 2,3,4-tris-O-[N-[2,3-di-(hydroxy)-benzoyl]-aminopropyl]-alpha-D-glucopyranoside.

Journal Article Inorganic chemistry · December 2001 The synthesis of two saccharide-based enterobactin analogues, methyl 2,3,4-tris-O[-N[2,3-di(hydroxy)benzoyl-glycyl]-aminopropyl]-alpha-D-glucopyranoside (H(6)L(A)) and methyl 2,3,4-tris-O-[N-[2,3-di(hydroxy)benzoyl]-aminopropyl]-alpha-D-glucopyranoside (H( ... Full text Cite

31P NMR probes of chemical dynamics: paramagnetic relaxation enhancement of the (1)H and (31)P NMR resonances of methyl phosphite and methylethyl phosphate anions by selected metal complexes.

Journal Article Inorganic chemistry · December 2001 Methyl phosphite ((CH(3)O)P(H)(O)(2)(-); MeOPH) and methylethyl phosphate ((CH(3)O)P(OCH(2)CH(3))(O)(2)(-); MEP) are two members of a class of anionic ligands whose (31)P T(2) relaxation rates are remarkably sensitive to paramagnetic metal ions. The temper ... Full text Cite

Synthesis, ligand pK(a), and Fe(III) complexation constants for a series of bipodal dihydroxamic acids.

Journal Article Inorg Chem · November 5, 2001 The synthesis of four bipodal dihydroxamic acids containing an apical C atom and amide linkages is described, where Ia,b represent "normal" and "retro" hydroxamate isomers: (R)CH[C(=O)NH(CH(2))(2)NHC(=O)(CH(2))(n)()R'](2) (Ia, R = CH(3), R' = N(OH)(C=O)CH( ... Full text Link to item Cite

Optimization of the lariat ether carboxylic acid host structure for ferrioxamine B: demonstration of a second coordination shell chelate effect.

Journal Article Inorganic chemistry · November 2001 Host-guest supramolecular assembly formation constants involving the second-sphere complexation of the siderophore ferrioxamine B (FeHDFB(+)) by a lariat ether carboxylic acid host (L(n+2)COOH) in wet chloroform were obtained from liquid-liquid extractions ... Full text Cite

Crystal structure of ferrioxamine B: a comparative analysis and implications for molecular recognition.

Journal Article Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry · October 2001 Ferrioxamine B was successfully co-crystallized with ethanolpentaaquomagnesium(II) and perchlorate ions as counter ions, C27H62Cl3FeMgN6O26, and the crystal structure has been determined by single-crystal X-ray diffraction. The crystals are monoclinic, spa ... Full text Cite

Use of SDS micelles to stabilize a ternary intermediate in the reaction of ferrioxamine B and 1,10-phenanthroline.

Journal Article Inorganic chemistry · October 2001 Spectrophotometric measurements of the reaction of ferrioxamine B (FeHDFB(+)) with 1,10-phenanthroline (phen) reveal the presence of a ternary intermediate complex in both aqueous solution and an aqueous solution of 0.16 M sodium dodecyl sulfate (SDS). The ... Full text Cite

Electron-induced inversion of helical chirality in copper complexes of N,N-dialkylmethionines

Journal Article Chemtracts · August 6, 2001 The researchers have successfully demonstrated that by generating a change in the redox state of the central metal ion, in a conformationally biased complex, they are able to effect a change in the ligand-binding mode. This change in the first coordination ... Cite

Microbial iron transport via a siderophore shuttle: A membrane ion transport paradigm

Journal Article Chemtracts · August 6, 2001 The siderophore-mediated iron transport in A. hydrophila was found to occur by means of a siderophore transport system with a very low specificity. At least two groups of transport systems were found to be present in A. hydrophila, of which one of them was ... Cite

Kinetics and mechanism of a catalytic chloride ion effect on the dissociation of model siderophore hydroxamate-iron(III) complexes.

Journal Article Inorganic chemistry · August 2001 Proton-driven ligand dissociation kinetics in the presence of chloride, bromide, and nitrate ions have been investigated for model siderophore complexes of Fe(III) with the mono- and dihydroxamic acid ligands R(1)C(=O)N(OH)R(2) (R(1) = CH(3), R(2) = H; R(1 ... Full text Cite

Fe3+ coordination and redox properties of a bacterial transferrin.

Journal Article The Journal of biological chemistry · January 2001 The Fe(3+) binding site of recombinant nFbp, a ferric-binding protein found in the periplasmic space of pathogenic Neisseria, has been characterized by physicochemical techniques. An effective Fe(3+) binding constant in the presence of 350 microm phosphate ... Full text Cite

Aqueous solution speciation of Fe(III) complexes with dihydroxamate siderophores alcaligin and rhodotorulic acid and synthetic analogues using electrospray ionization mass spectrometry.

Journal Article Inorg Chem · January 1, 2001 Aqueous solutions of Fe3+ complexes of cyclic (alcaligin) and linear (rhodotorulic acid) dihydroxamate siderophores and synthetic linear eight-carbon-chain and two-carbon-chain dihydroxamic acids ([CH3N(OH)C=O)]2(CH2)n; H2Ln; n = 2 and 8) were investigated ... Full text Link to item Cite

Can octahedral t2g6 complexes substitute associatively? The case of the isoelectronic Ruthenium(II) and Rhodium(III) hexaaquaions

Journal Article Chemtracts · January 1, 2001 The hexaaquaions of Rh(III) and Ru(II) seem to undergo water exchange via disparate mechanisms in spite of being isoelectronic in nature. The possibility for a t2g6 ion to undergo ligand substitution reaction via an Ia mechanism definitely complicates simp ... Cite

Kinetics and mechanism of iron(III) dissociation from the dihydroxamate siderophores alcaligin and rhodotorulic acid.

Journal Article Inorganic chemistry · December 2000 The kinetics and mechanism of siderophore ligand dissociation from their fully chelated Fe(III) complexes is described for the highly preorganized cyclic tetradentate alcaligin and random linear tetradentate rhodotorulic acid in aqueous solution at 25 degr ... Full text Cite

Concentration-dependent effects of anions on the anaerobic oxidation of hemoglobin and myoglobin.

Journal Article The Journal of biological chemistry · December 2000 The redox potentials of hemoglobin and myoglobin and the shapes of their anaerobic oxidation curves are sensitive indicators of globin alterations surrounding the active site. This report documents concentration-dependent effects of anions on the ease of a ... Full text Cite

Mutations at the histidine 249 ligand profoundly alter the spectral and iron-binding properties of human serum transferrin N-lobe: Mutation of the iron ligand His 249 to Glu in the N-lobe of human transferrin abolishes the dilysine "Trigger" but does not significantly affect iron release

Journal Article Chemtracts · December 1, 2000 Desired mutations were successfully introduced to the N-lobe of human transferrin in which Glu, Gln, and Ala replaced His 249. The structural analysis of H249E mutant was successfully carried out and was compared with the wild type. The pH stability of the ... Cite

Treatment of iron deficiency anemia: are monomeric iron compounds suitable for parenteral administration?

Journal Article The Journal of laboratory and clinical medicine · November 2000 Iron deficiency is the most common nutritional problem worldwide, especially in the developing countries. Oral iron supplementation programs have failed because of noncompliance and gastrointestinal toxicity, thereby necessitating parenteral administration ... Full text Cite

Multiple-path dissociation mechanism for mono- and dinuclear tris(hydroxamato)iron(III) complexes with dihydroxamic acid ligands in aqueous solution.

Journal Article Inorganic chemistry · September 2000 Linear synthetic dihydroxamic acids ([CH3N(OH)C=O)]2(CH2)n; H2Ln) with short (n = 2) and long (n = 8) hydrocarbon-connecting chains form mono- and dinuclear complexes with Fe(III) in aqueous solution. At conditions where the formation of Fe2(Ln)3 is favore ... Full text Cite

Microcalorimetric determination of thermodynamic parameters for ionophore-siderophore host-guest complex formation.

Journal Article Inorganic chemistry · March 2000 Thermodynamic parameters (delta H, delta S, and delta G) were determined by microcalorimetry in wet chloroform for host-guest assembly formation involving second-sphere complexation of the siderophore ferrioxamine B by crown ether (18-crown-6, cis-dicycloh ... Full text Cite

Electrochemical Behavior of the Fe(III) Complexes of the Cyclic Hydroxamate Siderophores Alcaligin and Desferrioxamine E.

Journal Article Inorg Chem · February 8, 1999 The redox behavior of Fe(III) complexes of the cyclic hydroxamate siderophores alcaligin and desferrioxamine E was investigated by cyclic voltammetry. The limiting, pH independent redox potential (E(1/2) vs NHE) is -446 mV for alcaligin above pH 9 and -477 ... Full text Link to item Cite

Internal electron transfer between hemes and Cu(II) bound at cysteine beta93 promotes methemoglobin reduction by carbon monoxide.

Journal Article The Journal of biological chemistry · February 1999 Previous studies showed that CO/H2O oxidation provides electrons to drive the reduction of oxidized hemoglobin (metHb). We report here that Cu(II) addition accelerates the rate of metHb beta chain reduction by CO by a factor of about 1000. A mechanism wher ... Full text Cite

Spectroelectrochemistry of heme proteins: effects of active-site heterogeneity on Nernst plots.

Journal Article Bioelectrochemistry and bioenergetics (Lausanne, Switzerland) · February 1999 In order to detect and model the effect of functional chain heterogeneity on Nernst plots for heme proteins, we examined the redox properties of various myoglobins (Mbs) and their mixtures using an improved spectroelectrochemical method. Specific redox res ... Full text Cite

Interpretation of activation volumes for water exchange reactions revisited: Ab initio calculations for Al3+, Ga3+, and In3+, and new experimental data

Journal Article Chemtracts · February 1, 1999 Rates of water exchange (k298) for spherically symmetric metal ions can be simulated by ab initio calculations, and are influenced by the size of the metal ion (ri) and overall charge of the aqua complex (Z). For these aquated ions where ligand-field effec ... Cite

Bulk liquid membrane transport of ferrioxamine B by neutral and ionizable carriers

Journal Article Journal of the Chemical Society - Dalton Transactions · December 7, 1998 Bulk liquid membrane (BLM) transport of ferrioxamine B (FeHDFB+) across an artificial hydrophobia membrane facilitated by neutral and ionizable carriers was studied. Under controlled conditions, ferrioxamine B transport by neutral ionophores follows a simp ... Full text Cite

Pronounced axial thiolate ligand effect on the reactivity of high-valent oxo-iron porphyrin intermediate

Journal Article Chemtracts · May 1, 1998 These researchers provide experimental evidence which shows that the influence of thiolate ligation on the oxidizing ability of the high-valent oxo-iron intermediate likely comes from the ability of the thiolate ligand to stabilize an oxygen radical struct ... Cite

Conformational fluctuations in deoxy hemoglobin revealed as a major contributor to anionic modulation of function through studies of the oxygenation and oxidation of hemoglobins A0 and Deer Lodge beta2(NA2)His --> Arg.

Journal Article Biochemistry · January 1998 Organisms rely on regulation at the molecular level, such as the allosteric regulation of hemoglobin (Hb) function by anions, to meet challenges presented by changing environmental and physiological conditions. A comparison of the effects of anions on oxyg ... Full text Cite

Lariat Ether Carboxylic Acids as Ionizable Hosts in the Second Coordination Sphere of the Siderophore Ferrioxamine B in Chloroform

Journal Article Inorganic Chemistry · January 1, 1998 A new series of lariat ether carboxylic acids (LnCOOH) was synthesized with different lengths of side arm (6, 9, and 12 atom spacers between the benzo-18-crown-6 crown ether ring and the carboxylic acid functional group). These lariat ethers were used as n ... Full text Cite

The release of iron from different asbestos structures by hydrogen peroxide with concomitant O2 generation.

Journal Article Biometals · January 1998 Treatment of aqueous suspensions of different asbestos fibers (amosite, anthophyllite, chrysotile, and crocidolite) at 0-4 degrees C and pH 7.2 with H2O2 results in the consumption of H2O2 with concomitant release of iron and production of O2. During incub ... Full text Link to item Cite

Molecular Recognition of Ferrioxamine B by Host-Guest Complex Formation with Lasalocid A in Chloroform

Journal Article Inorganic Chemistry · January 1, 1998 The polyether carboxylic acid antibiotic lasalocid A was employed as an ionophore in the extraction of ferrioxamine B (FeHDFB+ from H2O to CHC13 at aqueous pH 3 and pH 9. Lasalocid can selectively recognize and extract FeHDFB+ in the presence of the cation ... Full text Cite

A Determination of the Reduction Potentials for Diferric and C- and N-Lobe Monoferric Transferrins at Endosomal pH (5.8)

Journal Article Inorganic Chemistry · January 1, 1998 Human transferrin is a bilobal protein, with two Fe(III) binding sites displaying different spectroscopic, kinetic, and thermodynamic properties despite identical ligand donor groups. We present a spectroelectrochemical determination of the formal Fe(III/I ... Full text Cite

Solvent effect on second-sphere coordination of ferrioxamine B with substituted 18-crown-6 and 30-crown-10 crown ethers in dichloromethane as compared to chloroform

Journal Article Inorganica Chimica Acta · July 15, 1997 Stability constants for the second-sphere association of picrate and perchlorate salts of ferrioxamine B (FeHDFB+) with the substituted crown ethers (CE) 18-crown-6, cis-dicyclohexano-18-crown-6, benzo-18-crown-6, dibenzo-18-crown-6 and dibenzo-30-crown-10 ... Full text Cite

Hypothesis: iron chelation plays a vital role in neutrophilic inflammation.

Journal Article Biometals · April 1997 Neutrophil influx into tissues occurs in many diverse diseases and can be associated with both beneficial and injurious effects. We hypothesize that the stimulus for certain neutrophilic inflammatory responses can be reduced to a series of competing reacti ... Full text Link to item Cite

Mediator-free amperometric determination of toxic substances based on their inhibition of immobilized horseradish peroxidase.

Journal Article Biotechnology progress · September 1996 We have demonstrated the feasibility of quantitatively detecting selected toxic materials through their inhibitory effect on an enzyme electrode that utilizes colloidal gold-immobilized horseradish peroxidase and does not require a mediator. Quantitative d ... Full text Cite

Second-Sphere Coordination of Ferrioxamine B and Association of Deferriferrioxamine B, CH(3)(CH(2))(4)NH(3)(+), NH(4)(+), K(+), and Mg(2+) with Synthetic Crown Ethers and the Natural Ionophores Valinomycin and Nonactin in Chloroform.

Journal Article Inorg Chem · April 10, 1996 The interaction of ferrioxamine B, FeHDFB(+), through a protonated amine side chain, with various host ionophore structures to form a host-guest complex in the second coordination shell has been investigated. Host-guest association constants (K(a)) in wate ... Full text Link to item Cite

Molecular recognition of stable metal complexes through second-sphere coordination by macrocycles

Journal Article Pure and Applied Chemistry · January 1, 1996 An investigation of second coordination shell complexation of ferrioxamine B by crown ethers, natural ionophores, and other macrocycles through host-guest complexation of the pendant protonated amine group is presented. The influence of guest structure, ho ... Full text Cite

Second-Sphere Coordination of Ferrioxamine B and Association of Deferriferrioxamine B, CH3(CH2)4NH3+, NH4+, K+, and Mg2+ with Synthetic Crown Ethers and the Natural lonophores Valinomycin and Nonactin in Chloroform

Journal Article Inorganic Chemistry · 1996 The interaction of ferrioxamine B, FeHDFB+, through a protonated amine side chain, with various host ionophore structures to form a host-guest complex in the second coordination shell has been investigated. Host-guest association constants (Ka) in water sa ... Cite

A xanthine oxidase/colloidal gold enzyme electrode for amperometric biosensor applications

Journal Article Biosensors and Bioelectronics · January 1, 1996 An electrode has been prepared based on xanthine oxidase adsorbed to colloidal gold and evaporated onto the surface of glassy carbon. This electrode responds to xanthine or hypoxanthine in the absence of added mediator by electrochemical oxidation of the e ... Full text Cite

Stereochemical factors affecting second-sphere co-ordination of ferrioxamine B with cis-syn-cis and cis-anti-cis isomers of dicyclohexano-18-crown-6 in chloroform and a comparison with alkali-metal and ammonium cations

Journal Article Journal of the Chemical Society, Dalton Transactions · December 1, 1995 Second-sphere co-ordination of ferrioxamine B [Fe(HL)]+ by dicyclohexano-18-crown-6 (eicosahydrodibenzo[b,k][1,4,7,10,13,16]hexaoxacyclooctadecine) occurs through host-guest complex formation with the protonated amine side chain (CH2)5NH3+. The influence o ... Full text Cite

A spectroelectrochemical method for differentiation of steric and electronic effects in hemoglobins and myoglobins.

Journal Article The Journal of biological chemistry · June 1995 Spectroelectrochemical techniques are described which enable us to compare anion effects on redox curves of structurally distinct hemoglobins with oxygenation curves obtained under equivalent conditions. Nernst plots for tetrameric vertebrate Hbs show evid ... Full text Cite

Influence of the Anion on the Stability of Second-Sphere Coordination of Ferrioxamine B with cis-Dicyclohexano-18-crown-6 in Chloroform

Journal Article Inorganic Chemistry · February 1, 1995 The influence of the anion X− on the stability of the supramolecular assembly FeHDFB+,CE,X− (I) where FeHDFB+ is ferrioxamine B, CE is dicyclohexano-18-crown-6, and X− is ClO4−, NO3−, Cl−, or picrate was investigated. The formation constants for these host ... Full text Cite

Dihydroxamic acid complexes of iron (III): ligand pKa and coordinated water hydrolysis constants

Journal Article Inorganica Chimica Acta · January 1, 1995 A series of dihydroxamic acid ligands of the formula [RN(OH)C(O)]2(CH2)n, (n = 2, 4, 6, 7, 8; R = CH3, H) has been studied in 2.0 M aqueous sodium perchlorate at 25.0 °C. These ligands may be considered as synthetic analogs to the siderophore rhodotorulic ... Full text Cite

Detection thresholds of potassium salts are related to the molar conductivity of the anion.

Journal Article Brain research bulletin · January 1995 In a previous study, we found that human taste detection thresholds for Na+ salts were linearly correlated with molar conductivity values at infinite dilution of their anions. In the present study, detection threshold concentrations for potassium salts wer ... Full text Cite

A Monomer-to-Dimer Shift in a Series of 1:1 Ferric Dihydroxamates Probed by Electrospray Mass Spectrometry

Journal Article Inorganic Chemistry · December 1, 1994 Electrospray mass spectrometry (ESMS) was used to determine the stoichiometry of a series of 1:1 iron(III) complexes with model dihydroxamic acids H2L, [CH3N(OH)C(O)]2(CH2)n, and with the natural dihydroxamate siderophore rhodotorulic acid, RA. Parent (or ... Full text Cite

Phagocyte-generated superoxide reduces Fe3+ to displace it from the surface of asbestos.

Journal Article Archives of biochemistry and biophysics · December 1994 Injury after exposure to mineral oxide dusts is considered to be mediated by free radical generation. In vitro production of hydroxyl radical by a fibrous silicate increases with the [Fe3+] complexed to the dust surface. The study hypothesis tested was tha ... Full text Cite

Mechanistic Studies on the Dissociation of Mono- and Bimetallic 1:1 Ferric Dihydroxamate Complexes: Probing Structural Effects in Siderophore Dissociation Reactions

Journal Article Inorganic Chemistry · October 1, 1994 A pH-jump kinetic technique was used to monitor the dissociation of a series of iron(III) complexes with dihydroxamic acids [CH3N(OH)C(O)]2(CH2)n having a 1:1 metal-to-ligand ratio. For the initial step involving dissociation of one hydroxamate group from ... Full text Cite

Dissociation Kinetics of (N-Methylacetohydroxamato)iron(III) Complexes: A Model for Probing Electronic and Structural Effects in the Dissociation of Siderophore Complexes

Journal Article Inorganic Chemistry · August 1, 1994 The proton-initiated dissociation kinetics and equilibria of the mono, bis, and tris complexes of iron(III) with N-methylacetohydroxamic acid (NMHA) were studied under conditions of 2.0 M NaClO4/HClO4 at 25 °C. The proton-dependent rate constants k3, k2, a ... Full text Cite

Hydrolysis of Ferrioxamine B in Aqueous Micellar Solution

Journal Article Inorganic Chemistry · July 1, 1994 The association constant for the Fe(III) complex of the linear trihydroxamic acid siderophore ferrioxamine B (FeHDFB+; HDFB2- = H3N-[(CH2)5-N(O)C(O)-(CH2)2C(O)NH-)]2(CH2)5-N(O)C(O)-CH3) binding to sodium dodecyl sulfate (SDS) micelles was determined by ult ... Full text Cite

Supramolecular Assembly Formation of Ferrioxamine B and Its Al(III), Ga(III), and In(III) Analogues with Dicyclohexano-18-Crown-6 in Chloroform

Journal Article Journal of the American Chemical Society · June 1, 1994 We have shown that the crown ether dicyclohexano-18-crown-6 recognizes the terminal amine group of deferriferrioxamine B (H4DFB+) and its Al(III), Ga(III), Fe(III), and In(III) complexes (MHDFB+) by host-guest complex formation. Host-guest formation consta ... Full text Cite

DNA strand breaks following in vitro exposure to asbestos increase with surface-complexed [Fe3+].

Journal Article Archives of biochemistry and biophysics · May 1994 Surface functional groups on silicate dusts complex iron cations which can cycle through reduction and oxidation states to generate free radicals. These oxidants have a capacity to produce DNA strand breaks and mutations which are primary events in cancer ... Full text Cite

Electrospray Mass Spectrometry Study of 1:1 Ferric Dihydroxamates

Journal Article Inorganic Chemistry · March 1, 1994 Full text Cite

Formation of Plasma Polymer Thin Films Containing Reactive Metal Chelate Sites

Journal Article Chemistry of Materials · February 1, 1994 We report here the successful incorporation of chemically active Co2+ and Ni2+ centers into plasma polymer thin films. Metal center incorporation was accomplished by simultaneous plasma polymerization of sublimed Co2+ or Ni2+ complexes with gaseous “comono ... Full text Cite

A spectroelectrochemical method for evaluating factors which regulate the redox potential of hemoglobins

Journal Article Inorganica Chimica Acta · January 1, 1994 Spectroelectrochemical techniques were used to evaluate the redox potential of various hemoglobins under various experimental conditions. We use Ru(NH3)63+ as a redox mediator, which exchanges electrons with heme iron through an outer-sphere mechanism. Use ... Full text Cite

Synthesis and structural studies of new polyhydroxamic iron(III) complexes for the use in nuclear magnetic resonance imaging. Part II: Study of the complexes formed in situ from hydroxamic acids

Journal Article Canadian Journal of Chemistry · 1994 Numerous analogous dihydroxamates of rhodotorulic acid have been prepared, and their mode of complexation of iron(III) and the stability of these complexes studied as a function of pH, for comparison wimh ferrioxamine B and the complex of acetohydroxamic a ... Cite

Synthesis and structural studies of new polyhydroxamic iron(III) complexes for the use in nuclear magnetic resonance imaging. Part II: Study of the complexes formed in situ from hydroxamic acids

Journal Article Canadian Journal of Chemistry · January 1, 1994 Numerous analogous dihydroxamates of rhodotorulic acid have been prepared, and their mode of complexation of iron(III) and the stability of these complexes studied as a function of pH, for comparison wimh ferrioxamine B and the complex of acetohydroxamic a ... Full text Cite

Redox Properties of Phosphazene Polymers with Pendant Ferrocene Groups

Journal Article Inorganic Chemistry · January 1, 1993 The electrochemistry of a series of phosphazene polymers {[Ph(Me)=N] x[Ph{R′RC(OH)CH2}P=N]y}n where R′ is (η5C5H4)Fe(η5C5H5) with varying degrees of ferrocene substitution (3, x = 0.94, y = 0.06, R = H; 4, x = 0.80, y = 0.20, R = H; 5, x = 0.64, y = 0.36 ... Full text Cite

A carrageenan hydrogel stabilized colloidal gold multi-enzyme biosensor electrode utilizing immobilized horseradish peroxidase and cholesterol oxidase/cholesterol esterase to detect cholesterol in serum and whole blood.

Journal Article Biosensors & bioelectronics · January 1993 The preparation of two immobilized enzyme electrodes is described. One electrode contains horseradish peroxidase absorbed to colloidal gold and deposited on a glassy carbon electrode along with cholesterol oxidase entrapped in a carrageenan hydrogel. The s ... Full text Cite

Role of surface complexed iron in oxidant generation and lung inflammation induced by silicates.

Journal Article The American journal of physiology · November 1992 Inhalation of silicates induces a variety of lung diseases in humans. The molecular mechanism(s) by which these dusts cause disease is not known. Because several naturally occurring mineral oxides have large amounts of transition metal ions on their surfac ... Full text Cite

Colloidal gold as a biocompatible immobilization matrix suitable for the fabrication of enzyme electrodes by electrodeposition.

Journal Article Biotechnology and bioengineering · August 1992 Glucose oxidase, horseradish peroxidase, xanthine oxidase, and carbonic anhydrase have been adsorbed to colloidal gold sols with good retention of enzymatic activity. Adsorption of xanthine oxidase on colloidal gold did not result in a change in enzymatic ... Full text Cite

Direct electron transfer at horseradish peroxidase-colloidal gold modified electrodes

Journal Article Journal of Electroanalytical Chemistry · June 10, 1992 The reduction of H2O2 on horseradish peroxidase (HRP) and horseradish peroxidase-gold sol (HRP-Au) modified electrodes has been studied with and without an electron transfer mediator. The amplification effect owing to the enzyme-catalyzed turnover of subst ... Full text Cite

Triallylphosphine plasma polymerization and reaction of the product with volatile transition metal compounds

Journal Article Journal of Applied Polymer Science · January 1, 1992 The plasma polymerization of triallylphosphine in order to form a crosslinked polymer thin film is described. The plasma polymer thin film has been characterized and shown to contain a high proporation of CC and P groups conserved from the monomer. The ac ... Full text Cite

Comparison of colloidal gold electrode fabrication methods: the preparation of a horseradish peroxidase enzyme electrode.

Journal Article Biosensors & bioelectronics · January 1992 In order to prepare biosensing electrodes which respond to hydrogen peroxide, horseradish peroxidase has been adsorbed to colloidal gold sols and electrodes prepared by deposition of these enzyme-gold sols onto glassy carbon using three methods: evaporatio ... Full text Cite

Preparation of a plasma polymer containing phosphine complexed nickel by concurrent nickel evaporation

Journal Article Journal of Applied Polymer Science · January 1, 1992 This article describes one of the first examples of concurrent metal evaporation and substituted hydrocarbon plasma polymerization as a general method for preparing thin films containing a metal coordinated to a plasma polymer. In this report, the evaporat ... Full text Cite

Characterization of carrageenan hydrogel electrode coatings with immobilized cationic metal complex redox couples

Journal Article Journal of Physical Chemistry · January 1, 1992 The redox behavior of cationic metal complexes immobilized in a κ-carrageenan hydrogel matrix, which acts as a cation-exchange polymeric electrode coating, is described. Ru(bpy)32+, Ru(en)33+, Ru(NH3)63+, and Co(bpy)33+ (bpy = 2,2′-bipyridine; en = ethylen ... Full text Cite

Electrochemistry and Photocurrents of the Tris(bipyridine)ruthenium(II) and Methyl Viologen Cations Immobilized in Carrageenan Hydrogel

Journal Article Inorganic Chemistry · November 1, 1991 A procedure for immobilization of both a photochromophore, tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)32+), and a quencher, methyl viologen (MV2+), within a carrageenan hydrogel matrix at an electrode surface is described. Ru(bpy)32+ and MV2+ exhibited dif ... Full text Cite

The effect of an applied potential on the activity of carbonic anhydrase immobilized on graphite rods.

Journal Article Biotechnology and bioengineering · March 1991 The effect of both a positive and a negative applied potential on the p-NPA hydrolysis activity of bovine carbonic anhydrase (BCA) immobilized on graphite rods has been investigated. Background experiments show that the pH-activity profile for BCA free in ... Full text Cite

Thresholds for sodium salts in young and elderly human subjects: Correlation with molar conductivity of anion

Journal Article Chemical Senses · December 1, 1990 Taste detection thresholds in humans for eight out of ten sodium salts studied arc linearly correlated with molar conductivity values at infinite dilution of their anions. Thus, detection thresholds for these salts appear to be determineted by the charge m ... Full text Cite

The use of the methyl viologen neutral species as a mediator

Journal Article Journal of Electroanalytical Chemistry · November 26, 1990 The use of methyl viologen (MV) neutral species as a mediator for the reduction of CH3I and the methanogenic bacterial nickel-containing cofactor F430 is reported. Solutions of MV0 were generated using a potential step electrolysis procedure in which MV.+ ... Full text Cite

Iron bioavailability and the coordination chemistry of hydroxamic acids

Journal Article Coordination Chemistry Reviews · November 1, 1990 The mechanism of iron bioavailability and the principles underlying siderophore affinity and specificity for iron are briefly reviewed. The kinetics and mechanism of iron dissociation from ferrioxamine B under conditions of low pH, or competing ligands, is ... Full text Cite

Hypothesis: is lung disease after silicate inhalation caused by oxidant generation?

Journal Article Lancet (London, England) · October 1990 Inhaled silicate dusts may cause lung disease through their surface coordination of iron with subsequent oxidant generation via the Fenton reaction. Pneumoconiosis, irritant bronchitis, focal emphysema, and carcinoma may be produced by oxidants either dire ... Full text Cite

Activity of carbonic anhydrase immobilized on porous silica beads in organic media

Journal Article Biotechnology and Applied Biochemistry · April 18, 1990 Cite

Electrochemistry of heat-extracted methanogenic bacterial cofactor F430

Journal Article Inorganica Chimica Acta · April 17, 1990 Full text Cite

The influence of rigid cyclic phosphine ligands in cis-Rh(COD)-(phosphine)2+ on inner coordination shell dynamics and catalyzed olefin hydrogenation/isomerization

Journal Article Journal of Organometallic Chemistry · March 13, 1990 Conformational barriers in cis-phosphine-rhodium(I) complexes with two pairs of isomeric ligands (Rh(COD)(L)2+, L = anti- or syn-9-phenylphosphabicyclo[4.2.1]nona-2,4,7-triene (1 or 2) or L = anti- or syn-9-phenylphosphatricyclo[4.2.1.02,5]nona-7-ene (3 or ... Full text Cite

Plasma polymers containing uniformly dispersed nickel

Journal Article Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering · January 1, 1990 In this communication the authors describe the formation and characterization of a plasma polymer containing transition metal atoms coordinated to phosphine functional groups. The phosphine group containing film was prepared by the plasma polymerization of ... Cite

Preparation of plasma polymers containing ligated transition metal atoms

Journal Article Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering · January 1, 1990 The focus of the work reported in this paper is to form transition metal containing plasma polymers existing ideally as a single phase. In such preparations the transition metal atoms are complexed by functional groups within a plasma polymer. Electrochemi ... Cite

The design of magnetic resonance contrast agents: New iron (III) dihydroxamate complexes

Journal Article Tetrahedron Letters · January 1, 1990 We have prepared a series of dihydroxamates and their iron (III) complexes in view of obtaining new NMR imaging agents. Four new dihydroxamic acid ligands have been synthesized by condensation of 4-substituted-2,6-pyridine dicarboxylic acids with N-aminopr ... Full text Cite

A Comparison of Some Aspects of the Aqueous Coordination Chemistry of Aluminum(lll) and Iron(lll)

Journal Article Comments on Inorganic Chemistry · September 1, 1988 The aqueous coordination chemistry of Al3~ and Fe3+is compared. The differences in electronegativities (xm), ionic radii (ri) and electron configuration (dn) for the two ions are shown to influence trends in aquo ion structure and reactivity, hydrolysis, a ... Full text Cite

Preparation and activity of carbonic anhydrase immobilized on porous silica beads and graphite rods.

Journal Article Biotechnology and bioengineering · May 1988 Techniques for the immobilization of bovine carbonic anhydrase (BCA) on porous silica beads and graphite are presented. Surface coverage on porous silica beads was found to be 1.5 x 10(-5) mmol BCA/m(2), and on graphite it was 1.7 x 10(-3) mmol BCA/m(2) no ... Full text Cite

Hydroxamic Acid Ligand-Exchange Kinetics at Hexaaquoaluminum Ion

Journal Article Inorganic Chemistry · November 1, 1987 Hydroxamic acid (HA) ligand-exchange kinetics have been investigated at 25 °C over the [H+] range 1.0-0.001 M (I = 1.0 M (HClO4/NaClO4)). A series of five synthetic hydroxamic acids (R1C(O)N(OH)R2) were chosen for study with varying R1and R2substituents as ... Full text Cite

Synthesis and characterization of iron(llI) chelating analogues of siderophores on organic solid supports

Journal Article Inorganica Chimica Acta · October 15, 1987 A series of iron(III)-selective chelating resins have been modeled after the structural features of the naturally occurring siderophore compounds with hydroxamate, catecholate and salicylate iron binding groups. Amberlite IRC-50 was derivatized via an acid ... Full text Cite

Kinetics and mechanism of aluminum(III)/siderophore ligand exchange: mono(deferriferrioxamine B)aluminum(III) formation and dissociation in aqueous acid solution

Journal Article Inorganica Chimica Acta · January 1, 1987 The kinetics and mechanism of a linear trihydroxamic acid siderophore (deferriferrioxamine B, H4DFB+) ligand exchange with Al(H2O)63+ to form mono(deferriferrioxamine B)aluminum(III) (Al(H2O)4H3DFB)3+ have been investigated at 25 °C over the [H+] range 0.0 ... Full text Cite

The synthesis, x-ray crystal structure, and solution characterization of a bis(diphosphine)-bridged dirhodium(I) complex containing a Rh2P4 six-membered ring

Journal Article Journal of the Chemical Society, Dalton Transactions · January 1, 1986 The preparation of [{Rh(cod)}2(μ-L1)2][BF4] 2 (1) from (CH2CMe=CH2P)2 (L1) and [Rh(cod)2]-BF4 (cod = cyclo-octa-1,5-diene) is described. The compound crystallizes in the monoclinic space group P21/c (C52h), with a = 9.650(1), b = 11.609(1), c = 21.884(3) Å ... Full text Cite

Retention of phosphorus configuration on forming irontetracarbonyl complexes with phosphines in the 9-phosphabicyclo[4.2.1]nonatriene and 7-phosphanorbornene systems

Journal Article Tetrahedron Letters · January 1, 1986 Dimers of phospholes with syn or anti configuration at the bridging phosphorus react with Fe2(CO)9 to give complexes, R3PFe(CO)4, with complete retention of configuration. Contrary to a report in the literature, isomers of 9-phenylbicyclo[4.2.1]nonatriene ... Full text Cite

Comparison of the Kinetics, Mechanism, and Thermodynamics of Aqueous Iron(III) Chelation and Dissociation by Hydroxamic Oxo and Thio Acid Ligands

Journal Article Inorganic Chemistry · July 1, 1985 The kinetics and thermodynamics of aqueous iron(III) complexation by 4-CH3OC6H4C(X)N(OH)H (X = O, S) to form Fe-(H2O)4(4-CH30C6H4C(X)N(0)H)2+ are reported. These data provide a direct comparison between the iron(III) chelation chemistry of hydroxamic oxo a ... Full text Cite

Fourier transform infrared photothermal spectroscopic characterization of Prussian blue surface modified electrodes. Countercation effects

Journal Article Journal of Physical Chemistry · January 1, 1985 Fourier transform infrared photothermal spectroscopy was used in conjunction with cyclic voltammetry to characterize graphite electrodes which were surface modified by the deposition of an iron-containing plasma polymer or iron-containing plasma deposit fo ... Full text Cite

Temperature-Dependent Acid Dissociation Constants (KaΔHa, ΔSa) for some C-Aryl Hydroxamic Acids: The Influence of C and N Substituents on Hydroxamate Anion Solvation in Aqueous Solution

Journal Article Journal of Organic Chemistry · January 1, 1985 The acid dissociation constants (Ka) of a series of substituted N-methylbenzohydroxaraic acids, 4-XC6H4C-(O)N(OH)CH3(X = H, CH3O, CH3, NO2) and 4-methoxybenzohydroxamic acid, 4-CH3OC6H4C(O)N(OH)H, have been determined in aqueous solution (I = 2.0) over a r ... Full text Cite

Transition metal containing plasma polymers

Journal Article Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films · January 1, 1985 The plasma polymerization of the C2 hydrocarbons in the presence of Fe(CO)5vapor can lead to the formation of soluble cluster complexes (I) and/or high oxidation state iron both in the form of the oxide (II) and associated with the carboxylate or β-diketon ... Full text Cite

CHEMICAL PROPERTIES OF METALLATED PLASMA POLYMERS.

Journal Article Applied Polymer Symposia · December 1, 1984 Transition-metal-containing plasma polymers and plasma deposits were formed by plasma-polymerizing pentacarbonyliron(0) or cyclopentadienyldicarbonylcobalt(I) either as sole monomers or as one component of a mixture with a C//2 hydrocarbon (ethane, ethylen ... Cite

Plasma polymerization of iron pentacarbonyl with C2 hydrocarbons

Journal Article Thin Solid Films · July 6, 1984 Iron-containing plasma polymers are deposited from a plasma using iron pentacarbonyl (Fe(CO)5) plus C2 hydrocarbons as comonomers and are characterized using a variety of techniques. The plasma polymers are found to contain high proportions of highly dispe ... Full text Cite

Preparation of tris(η5-cyclopentadienylcobaltmonocarbonyl) cluster complex by a plasma technique

Journal Article Inorganica Chimica Acta · March 15, 1984 The glow discharge reaction of cyclopentadienyldicarbonylcobalt(I) CpCo(CO)2 was carried out in an inductively coupled cylindrical reactor at various flow rates and rf power levels. The deposition rate at low ratios of power to flow rate (W/F) is highest n ... Full text Cite

Alkali metal cation effects in a prussian blue surface-modified electrode

Journal Article Inorganic Chemistry · January 1, 1984 Graphite electrodes were surface modified first by coating them in a glow discharge with iron pentacarbonyl (the resulting deposit called an iron-containing plasma deposit) or iron pentacarbonyl and ethane in a 1:1 molar ratio (the resulting deposit called ... Full text Cite

Kinetics, mechanism, and thermodynamics of aqueous iron(III) chelation and dissociation: Influence of carbon and nitrogen substituents in hydroxamic acid ligands

Journal Article Inorganic Chemistry · January 1, 1984 Thermodynamic and kinetic studies were performed to investigate the complexation of aqueous high-spin iron(III) by 12 bidentate hydroxamic acids, R1C(G)N(OH)R2, (R1 = CH3, C6H5, 4-NO2C6H4, 4-CH3C6H4, 4-CH3OC6H4; R2 = CH3, C6H5, 4-CH3C6H4, 4-ClC6H4,4-IC6H4, ... Full text Cite

Factors that influence siderophoremediated iron bioavailability: catalysis of interligand iron (III) transfer from ferrioxamine B to EDTA by hydroxamic acids.

Journal Article Journal of inorganic biochemistry · August 1983 Deferriferrioxamine B (H3DFB) is a linear trihydroxamic acid siderophore with molecular formula NH2(CH2)5[N(OH)C(O)(CH2)2C(O)NH(CH2)5]2N(OH)C(O)CH3 that forms a kinetically and thermodynamically stable complex with iron(III), ferrioxamine B. Under the cond ... Full text Cite

Use of a Metal-Containing Plasma Polymer Coating to Prepare a Prussian Blue Surface Modified Electrode

Journal Article Inorganic Chemistry · January 1, 1983 Graphite electrodes are surface modified by coating them in a glow-discharge plasma chamber with iron pentacarbonyl (the resulting deposit is called an iron-containing plasma deposit) or iron pentacarbonyl and ethane in a 1:1 molar ratio (the resulting dep ... Full text Cite

CHEMICAL PROPERTIES OF METALLATED PLASMA POLYMERS.

Journal Article Organic Coatings and Applied Polymer Science Proceedings · December 1, 1982 Cite

Temperature-Dependent Acid Dissociation Constants (Ka, ΔHa, ΔSa) for a Series of Nitrogen-Substituted Hydroxamic Acids in Aqueous Solution

Journal Article Journal of Organic Chemistry · January 1, 1982 The acid dissociation constants (Ka) of a series of eight substituted N-phenylacetohydroxamic acids, CH3C—(O)N(OH)C6H4X (X = H, 4-CH3, 4-Cl, 4-I, 3-I, 3-CN, 4-CN, 4-C(O)CH3), have been determined in aqueous solution (I = 2.0) for a range of temperatures. T ... Full text Cite

Kinetics and Mechanism of the Stepwise Dissociation of Iron(III) from Ferrioxamine B in Aqueous Acid

Journal Article Journal of the American Chemical Society · January 1, 1982 Deferriferrioxamine B (H3DFB) is a linear trihydroxamic acid siderophore with molecular formula NH2(CH2)5[N(OH)C(O)(CH2)2C(O)NH(CH2)5]2N(OH)C(O)CH3. In aqueous solution at pH 5, the siderophore forms a hexadentate chelate with iron(III), ferrioxamine B (Fe ... Full text Cite

Cobaloxime(II)-initiated coupling of α,α,α-trihalomethylbenzenes

Journal Article Journal of Organometallic Chemistry · July 28, 1981 Bis(dimethylglyoximato) complexes of cobalt(II), cobaloxime(II), under mild conditions initiate coupling of α,α,α-trihalomethylbenzenes to form PhCX2CX2Ph (X Cl), PhCXCXPh (X Cl, Br) and mixtures of halocobaloxime products. Stoichiometry, product distribut ... Full text Cite

Acid Dissociation Constants (Ka) and Their Temperature Dependencies (AHa, ASa) for a Series of Carbon- and Nitrogen-Substituted Hydroxamic Acids in Aqueous Solution

Journal Article Journal of Organic Chemistry · January 1, 1980 The acid dissociation constants (Ka) of a series of six C- and N-substituted hydroxamic acids, R1C(O)N(OH)R2 (R1 = CH3, C6H5; R2 = H, CH3, C6H5), have been determined in aqueous solution (I = 2.0) for a range of temperatures. In contrast to many other orga ... Full text Cite

Reaction of indoles with molecular oxygen catalyzed by metalloporphyrins

Journal Article Journal of Molecular Catalysis · January 1, 1980 Cobalt(II), cobalt(III), and manganese(III) meso-tetraphenylporphins catalyse the oxygenation of simple alkyl-substituted indoles, the latter complex being the most active catalyst. Spectroscopic data (uv, n.m.r., e.s.r.) indicate that during the reaction ... Full text Cite

Mechanism of Ligand Substitution on High-Spin Iron(III) by Hydroxamic Acid Chelators. Thermodynamic and Kinetic Studies on the Formation and Dissociation of a Series of Monohydroxamatoiron(III) Complexes

Journal Article Journal of the American Chemical Society · September 1, 1979 Thermodynamic and kinetic studies were performed to investigate the complexation of aqueous high-spin iron(III) by six bidentate hydroxamic acids, R1C(O)N(OH)R2(R1 = CH3 or C6H5 and R2 = H, CH3, or C6H5) in acid medium. Both complex formation and dissociat ... Full text Cite

The selection and evaluation of new chelating agents for the treatment of iron overload.

Journal Article The Journal of pharmacology and experimental therapeutics · January 1979 A large-scale systematic evaluation of potential iron chelators for the treatment of hemosiderosis was conducted. The compounds were identified and evaluated using a hypertransfused mouse screen in which deferrioxamine B was a standard. This screen was des ... Cite

Synthesis and Characterization of Neutral Thiocyanato-and Selenocyanato-Bridged Cobaloximes

Journal Article Inorganic Chemistry · January 1, 1979 Pseudohalides react with alkylcobaloximes to produce labile complexes [Co(dmgH)2(CNX)(R)]- (X=O, S, Se) where the linkage isomer preference is dependent upon X, the alkyl group R, and the solvent. Isomer equilibration occurs rapidly in solution and is not ... Full text Cite

Synthesis and Characterization of Neutral Cyano-Bridged Dicobaloximes. (Alkyl)cobaloxime-μ-cyano-(ligand)cobaloxime

Journal Article Inorganic Chemistry · September 1, 1976 The reaction of an alkylaquocobaloxime, Co(dmgH)2(R)(H2O), with a cyano(ligand)cobaloxime, Co(dmgH)2(CN)(B), has been found to produce a series of cyano-bridged dicobaloximes of the general formula R-Co(dmgH)2-NC-Co(dmgH)2-B (I). A series of 30 such cyano- ... Full text Cite

Synthesis of Monocyanocobaloximes

Journal Article Inorganic Chemistry · March 1, 1976 Full text Cite

Intermolecular Hydrogen Bonding in Protonated Diacidocobaloximes

Journal Article Inorganic Chemistry · November 1, 1975 The protonated diacidocobaloximes Co(dmgH)(dmgH2)(X)(Y), where X = Y = Cl-, X = Y = SCN-, X = Y = CN-, or X = SCN- and Y = CN-, have been shown from their infrared spectra to crystallize in such a way that intermolecular hydrogen bonding occurs. This inter ... Full text Cite

Kinetics of Oxidation of a Cuprous 2,2′,2″-Terpyridine Complex by Molecular Oxygen

Journal Article Inorganic Chemistry · July 1, 1975 2,2′,2″-Terpyridine (terpy) has been found to form a bis cuprous complex, Cu(terpy)2+, in aqueous acetonitrile solution. The reaction with molecular oxygen was found to proceed with a two-electron reduction of O2. [formula omitted] The kinetics of this rea ... Full text Cite

Radical decay kinetics in ferrocytochrome c model membranes. A spin label study.

Journal Article Journal of the American Chemical Society · March 1975 Full text Cite

Synthesis and Characterization of Protonated Alkylcobaloximes and Related Compounds

Journal Article Inorganic Chemistry · March 1, 1975 Five alkylaquocobaloximes1 have been protonated in aqueous solution to yield a series of crystalline compounds of the general formula [Co(dmgH)(dmgH)(R)(Cl)]H2O where R- = CH3-, C2H5-, n-C3H7-, l-C3H7-, or C6H11-. Protonation can also be achieved under str ... Full text Cite

Preparation and X-ray crystal structure of a novel tetranuclear copper(I) ethylenethiourea cluster complex, μ4-ethylenethiourea-cyclo- tetrakis-μ-(ethylenethiourea)tetrakis[ethylenethioureacopper(I)] nitrate hexahydrate

Journal Article Journal of the Chemical Society, Chemical Communications · January 1, 1974 The structure, geometry, and bonding in [Cu4(C3H 6N2S)9(NO3)4],6H 2O have been established by X-ray analysis which reveals discrete Cu4(C3H6N2S)94+ cations containing an alternating Cu-S eight-membered ring with a unique ethylenethiourea ligand in an axial ... Full text Cite

The synthesis of neutral cyano bridged dicobaloximes

Journal Article Inorganic and Nuclear Chemistry Letters · January 1, 1974 Full text Cite

Isolation and characterization of chloro(ethyl) dimethylglyoximatodimethylglyoximecobalt(III) hydrate. A protonated cobaloxime

Journal Article Journal of the Chemical Society, Chemical Communications · December 1, 1973 A monoprotonated cobaloxime, [EtCo(dmg)(dmgH)Cl]H2O, has been isolated and characterized by i.r., u.v., and X-ray methods which indicate a dimethylglyoxime oxygen as the site of protonation. ... Full text Cite

Isomeric Tetracyanoethylene Adducts of N,N'-Ethylenebis(acetylacetoniminato)cobalt(II)

Journal Article Inorganic Chemistry · August 1, 1971 The reaction of tetracyanoethylene (TCNE) with N,N'-ethylenebis(acetylacetoniminato)cobalt(II), Co(acacen), in various solvents is described. A microcrystalline air-sensitive reaction product has been isolated in the presence of pyridine (py), in a green a ... Full text Cite

Substitution Kinetics of Alkylbis(dimethylglyoximato)aquocoball(III) in Aqueous Solution1 Sir

Journal Article Journal of the American Chemical Society · April 1, 1970 Full text Cite

Monomeric Oxygen Adducts of N,N′-Ethylenebis(acetylacetoniminato) ligandcobalt (II). Preparation and Properties

Journal Article Journal of the American Chemical Society · January 1, 1970 .Abstract: A series of monomeric molecular oxygen carriers of the general formula Co(acacen)(B)O2 (acacen = (CH3C(O-)=CHC(CH3)=NCH2-)2; B = N,N-dimethylformamide, pyridine, 4-aminopyridine, 4-methylpyridine, and 4-cyanopyridine) were prepared in nonaqueous ... Full text Cite

Monomeric cobalt-oxygen complexes.

Journal Article Science (New York, N.Y.) · June 1969 Some Schiff base complexes of cobalt(II) form stable cobalt-oxygen species in solution instead of the usual cobalt-oxygen-cobalt bridged complexes. These one-to-one adducts were isolated as crystalline solids and characterized by means of elemental analysi ... Full text Cite

Preparation and Chemistry of α-Chloroalkyllithium Compounds. Their Role as Carbenoid Intermediates1

Journal Article Journal of the American Chemical Society · January 1, 1965 The reaction of polychloromethanes with n-butyllithium in tetrahydrofuran at low temperatures (–100°) via a-metalation or halogen-metal interconversion has been used to prepare a new class of organolithium reagents, the α-chloroalkyllithium compounds I-IV. ... Full text Cite