1
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Bollmeyer MM, Majer SH, Coleman RE, Lancaster KM. Outer coordination sphere influences on cofactor maturation and substrate oxidation by cytochrome P460. Chem Sci 2023; 14:8295-8304. [PMID: 37564409 PMCID: PMC10411619 DOI: 10.1039/d3sc02288a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 06/22/2023] [Indexed: 08/12/2023] Open
Abstract
Product selectivity of ammonia oxidation by ammonia-oxidizing bacteria (AOB) is tightly controlled by metalloenzymes. Hydroxylamine oxidoreductase (HAO) is responsible for the oxidation of hydroxylamine (NH2OH) to nitric oxide (NO). The non-metabolic enzyme cytochrome (cyt) P460 also oxidizes NH2OH, but instead produces nitrous oxide (N2O). While both enzymes use a heme P460 cofactor, they selectively oxidize NH2OH to different products. Previously reported structures of Nitrosomonas sp. AL212 cyt P460 show that a capping phenylalanine residue rotates upon ligand binding, suggesting that this Phe may influence substrate and/or product binding. Here, we show via substitutions of the capping Phe in Nitrosomonas europaea cyt P460 that the bulky phenyl side-chain promotes the heme-lysine cross-link forming reaction operative in maturing the cofactor. Additionally, the Phe side-chain plays an important role in modulating product selectivity between N2O and NO during NH2OH oxidation under aerobic conditions. A picture emerges where the sterics and electrostatics of the side-chain in this capping position control the kinetics of N2O formation and NO binding affinity. This demonstrates how the outer coordination sphere of cyt P460 is tuned not only for selective NH2OH oxidation, but also for the autocatalytic cross-link forming reaction that imbues activity to an otherwise inactive protein.
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Affiliation(s)
- Melissa M Bollmeyer
- Baker Laboratory Department of Chemistry and Chemical Biology Cornell University 162 Sciences Drive Ithaca NY 14853 USA
| | - Sean H Majer
- Baker Laboratory Department of Chemistry and Chemical Biology Cornell University 162 Sciences Drive Ithaca NY 14853 USA
| | - Rachael E Coleman
- Baker Laboratory Department of Chemistry and Chemical Biology Cornell University 162 Sciences Drive Ithaca NY 14853 USA
| | - Kyle M Lancaster
- Baker Laboratory Department of Chemistry and Chemical Biology Cornell University 162 Sciences Drive Ithaca NY 14853 USA
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2
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Mazumdar R, Saha S, Samanta B, Mondal B. Can a Nitrosyl of a Mn(II)-Porphyrin Complex Release Nitroxyl/HNO? Inorg Chem 2021; 60:18024-18030. [PMID: 34797639 DOI: 10.1021/acs.inorgchem.1c02606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In general, the nitrosyl complexes of Mn(II)-porphyrinate having the {Mn(NO)}6 configuration are not considered as HNO or nitroxyl (NO-) donors because of [MnI-NO+] nature. A nitrosyl complex of Mn(II)-porphyrin, [Mn(TMPP2-)(NO)], 1 [TMPPH2 = 5,10,15,20-tetrakis-4-methoxyphenylporphyrin], is shown to release HNO in the presence of HBF4. It is evidenced from the characteristic reaction of HNO with triphenylphosphine and isolation of the [(TMPP2-)MnIII(H2O)2](BF4), 2. This is attributed to the fact that H+ from HBF4 polarizes the NO group whereas the BF4- interacts with metal ion to stabilize the Mn(III) form. These two effects cooperatively result in the release of HNO from complex 1. In addition, complex 1 behaves as a nitroxyl (NO-) donor in the presence of [Fe(dtc)3] (dtc = diethyldithiocarbamate anion) and [Fe(TPP)(Cl)] (TPP = 5,10,15,20-tetraphenylporphyrinate) to result in [Fe(dtc)2(NO)] and [Fe(TPP)(NO)], respectively.
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Affiliation(s)
- Rakesh Mazumdar
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Shankhadeep Saha
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Bapan Samanta
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Biplab Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
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3
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Rahman MH, Atifi A, Rosenthal J, Ryan MD. Reversible Proton-Coupled Reduction of an Iron Nitrosyl Porphyrin within [DBU-H] +-Based Protic Ionic Liquid Nanodomains. Inorg Chem 2021; 60:10631-10641. [PMID: 34232621 DOI: 10.1021/acs.inorgchem.1c01273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reduction of [Fe(OEP)(NO)] has been studied in the presence of aprotic room-temperature ionic liquids (RTIL) and protic (PIL) ionic liquids dissolved within a molecular solvent (MS). The cyclic voltammetric results showed the formation of RTIL nanodomains at low concentrations of the RTIL/PIL solutions. The pKa values of the two PILs studied (i.e., trialkylammonium and [DBU-H]+-based ionic liquids) differed by four units in THF. While voltammetry in solutions containing all three RTILs showed similar potential shifts of the first reduction of [Fe(OEP)(NO)] to [Fe(OEP)(NO)]- at low concentrations, significant differences were observed at higher concentrations for the ammonium PIL. The trialkylammonium cation had previously been shown to protonate the {FeNO}8 species at room temperature. Visible and infrared spectroelectrochemistry revealed that the [DBU-H]+-based PIL formed hydrogen bonds with [Fe(OEP)(NO)]- rather than formally protonating it. Despite these differences, both PILs were able to efficiently reduce the nitrosyl species to the hydroxylamine complex, which could be further reduced to ammonia. On the voltammetric time scale and when the switching potential was positive of the Fe(II)/Fe(I) potential, the hydroxylamine complex was re-oxidized back to the NO complex via direct oxidation of the coordinated hydroxylamine at low scan rates or initial oxidation of the ferrous porphyrin at high scan rates. The results of this work show that, while [DBU-H]+ does not protonate electrochemically generated [Fe(OEP)(NO)]-, it still plays an important role in efficiently reducing the nitroxyl ligand via a series of proton-coupled electron transfer steps to generate hydroxylamine and eventually ammonia. The overall reaction rates were independent of the PIL concentration, consistent with the nanodomain formation being important to the reduction process.
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Affiliation(s)
- Md Hafizur Rahman
- Chemistry Department, PO Box 1881, Marquette University, Milwaukee, Wisconsin 53201, United States
| | - Abderrahman Atifi
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Joel Rosenthal
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Michael D Ryan
- Chemistry Department, PO Box 1881, Marquette University, Milwaukee, Wisconsin 53201, United States
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4
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Abstract
In this review, DNA and nanomaterial based catalysts for porphyrin metalation reactions are summarized, including the selection of DNAzymes, choice of nanomaterials, their catalytic mechanisms, and applications of the reactions.
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Affiliation(s)
- Hualin Yang
- College of Life Science
- Yangtze University
- Jingzhou
- China
- Department of Chemistry
| | - Yu Zhou
- College of Life Science
- Yangtze University
- Jingzhou
- China
- College of Animal Science
| | - Juewen Liu
- Department of Chemistry
- Waterloo Institute for Nanotechnology
- University of Waterloo
- Waterloo
- Canada
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5
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Brown BN, Robinson KJ, Durfee QC, Kekilli D, Hough MA, Andrew CR. Hydroxylamine Complexes of Cytochrome c': Influence of Heme Iron Redox State on Kinetic and Spectroscopic Properties. Inorg Chem 2020; 59:14162-14170. [PMID: 32970420 DOI: 10.1021/acs.inorgchem.0c01925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydroxylamine (NH2OH or HA) is a redox-active nitrogen oxide that occurs as a toxic intermediate in the oxidation of ammonium by nitrifying and methanotrophic bacteria. Within ammonium containing environments, HA is generated by ammonia monooxygenase (nitrifiers) or methane monooxygenase (methanotrophs). Subsequent oxidation of HA is catalyzed by heme proteins, including cytochromes P460 and multiheme hydroxylamine oxidoreductases, the former contributing to emissions of N2O, an ozone-depleting greenhouse gas. A heme-HA complex is also a proposed intermediate in the reduction of nitrite to ammonia by cytochrome c nitrite reductase. Despite the importance of heme-HA complexes within the biogeochemical nitrogen cycle, fundamental aspects of their coordination chemistry remain unknown, including the effect of the Fe redox state on heme-HA affinity, kinetics, and spectroscopy. Using stopped-flow UV-vis and resonance Raman spectroscopy, we investigated HA complexes of the L16G distal pocket variant of Alcaligenes xylosoxidans cytochrome c'-α (L16G AxCP-α), a pentacoordinate c-type cytochrome that we show binds HA in its Fe(III) (Kd ∼ 2.5 mM) and Fe(II) (Kd = 0.0345 mM) states. The ∼70-fold higher HA affinity of the Fe(II) state is due mostly to its lower koff value (0.0994 s-1 vs 11 s-1), whereas kon values for Fe(II) (2880 M-1 s-1) and Fe(III) (4300 M-1 s-1) redox states are relatively similar. A comparison of the HA and imidazole affinities of L16G AxCP-α was also used to predict the influence of Fe redox state on HA binding to other proteins. Although HA complexes of L16G AxCP-α decompose via redox reactions, the lifetime of the Fe(II)HA complex was prolonged in the presence of excess reductant. Spectroscopic parameters determined for the Fe(II)HA complex include the N-O stretching vibration of the NH2OH ligand, ν(N-O) = 906 cm-1. Overall, the kinetic trends and spectroscopic benchmarks from this study provide a foundation for future investigations of heme-HA reaction mechanisms.
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Affiliation(s)
- Brianna N Brown
- Department of Chemistry and Biochemistry, Eastern Oregon University, La Grande, Oregon 97850, United States
| | - Kelsey J Robinson
- Department of Chemistry and Biochemistry, Eastern Oregon University, La Grande, Oregon 97850, United States
| | - Quentin C Durfee
- Department of Chemistry and Biochemistry, Eastern Oregon University, La Grande, Oregon 97850, United States
| | - Demet Kekilli
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, United Kingdom
| | - Michael A Hough
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, United Kingdom
| | - Colin R Andrew
- Department of Chemistry and Biochemistry, Eastern Oregon University, La Grande, Oregon 97850, United States
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6
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Mondal B, Borah D, Mazumdar R, Mondal B. Nitric Oxide Dioxygenase Activity of a Nitrosyl Complex of Mn(II)-Porphyrinate in the Presence of Superoxide: Formation of a Mn(IV)-oxo Species through a Putative Peroxynitrite Intermediate. Inorg Chem 2019; 58:14701-14707. [PMID: 31617355 DOI: 10.1021/acs.inorgchem.9b02359] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A nitrosyl complex of MnII-porphyrinate, [(F20TPP)MnII(NO)], 1 (F20TPPH2 = 5,10,15,20 tetrakis(pentafluorophenyl)porphyrin), was synthesized and characterized. Spectroscopic and structural characterization revealed complex 1 as a penta-coordinated MnII-nitrosyl with a linear Mn-N-O (180.0°) moiety. Complex 1 does not react with O2. However, it reacts with superoxide (O2-) in THF at -80 °C to result in the corresponding nitrate (NO3-) complex, 2, via the formation of a presumed MnIII-peroxynitrite intermediate. ESI-mass spectrometry and UV-visible and X-band EPR spectroscopic studies suggest the generation of MnIV-oxo species in the reaction through homolytic cleavage of the O-O bond of the peroxynitrite ligand as proposed in NOD activity. The intermediate formation of the MnIII-peroxynitrite was further supported by the well accepted phenol ring nitration which resembles the biologically well-established tyrosine nitration.
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Affiliation(s)
- Baishakhi Mondal
- Department of Chemistry , Indian Institute of Technology Guwahati , Assam 781039 , India
| | - Dibyajyoti Borah
- Department of Chemistry , Indian Institute of Technology Guwahati , Assam 781039 , India
| | - Rakesh Mazumdar
- Department of Chemistry , Indian Institute of Technology Guwahati , Assam 781039 , India
| | - Biplab Mondal
- Department of Chemistry , Indian Institute of Technology Guwahati , Assam 781039 , India
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7
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Rahman MH, Liu Y, Ryan MD. Proton Transfer versus Hydrogen Bonding in a Reduced Iron Porphyrin Nitrosyl Complex. Inorg Chem 2019; 58:13788-13795. [PMID: 31565930 DOI: 10.1021/acs.inorgchem.9b01447] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The 1H NMR spectra of Fe(OEP)(HNO), which was formed from Fe(OEP)(NO)- in the presence of 3,5-dichlorophenol, were studied as a function of temperature. The chemical shift of the HNO proton showed a unique behavior which could be explained based on the equilibrium between the protonated complex, Fe(OEP)(HNO), and the hydrogen-bonded complex, Fe(OEP)(NO)-···HOPh. This equilibrium was consistent with UV/visible spectroscopy and the voltammetric data. UV/visible stopped-flow experiments showed that the hydrogen-bonded complex, which was formed when weak acids such as phenol were added, and the Fe(OEP)(HNO) complex were quite similar. In addition to the HNO proton resonance, the meso-resonances were consistent with the proposed equilibrium. Density functional theory calculations of various Fe(OEP)(NO)-/Fe(OEP)(HNO) species were calculated, and the results were consistent with experimental data.
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Affiliation(s)
- Md Hafizur Rahman
- Chemistry Department , Marquette University , PO Box 1881, Milwaukee , Wisconsin 53201 , United States
| | - Yilin Liu
- Chemistry Department , Marquette University , PO Box 1881, Milwaukee , Wisconsin 53201 , United States
| | - Michael D Ryan
- Chemistry Department , Marquette University , PO Box 1881, Milwaukee , Wisconsin 53201 , United States
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8
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Rahman MH, Ryan MD. Investigation of solvation and solvent coordination effects in iron porphyrin nitrosyls by infrared spectroelectrochemistry and DFT calculations. J PORPHYR PHTHALOCYA 2019. [DOI: 10.1142/s1088424619500317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Visible and infrared spectroelectrochemistry of Fe(OEPone)(NO) (H2OEPone = octaethylporphinone) were examined in methylene chloride and THF. The visible spectra of Fe(OEPone)(NO) were similar in both solvents. Unlike other ferrous porphyrin nitrosyls, a six-coordinate complex was formed with THF as a ligand. This led to two nitrosyl bands in the infrared spectrum. The absorbance of these bands depended on the concentration of THF in the solution. Solvation and coordination effects on the carbonyl and nitrosyl bands were observed for both the nitrosyl and reduced-nitrosyl complexes. DFT calculations were carried out to interpret the spectral changes. Marquette University, Raynor Memorial Libraries, Chemistry Research Data: https://epublications.marquette.edu/chem_data/1/
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Affiliation(s)
- Md. Hafizur Rahman
- Chemistry Department, P.O. Box 1881, Marquette University, Milwaukee, WI 53201, USA
| | - Michael D. Ryan
- Chemistry Department, P.O. Box 1881, Marquette University, Milwaukee, WI 53201, USA
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9
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Smith MA, Majer SH, Vilbert AC, Lancaster KM. Controlling a burn: outer-sphere gating of hydroxylamine oxidation by a distal base in cytochrome P460. Chem Sci 2019; 10:3756-3764. [PMID: 31015919 PMCID: PMC6457333 DOI: 10.1039/c9sc00195f] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 02/14/2019] [Indexed: 01/19/2023] Open
Abstract
One amino acid makes the difference between a metalloenzyme and a metalloprotein in two otherwise effectively identical cytochrome P460s.
Ammonia oxidizing bacteria (AOB) use the cytotoxic, energetic molecule hydroxylamine (NH2OH) as a source of reducing equivalents for cellular respiration. Despite disproportionation or violent decomposition being typical outcomes of reactions of NH2OH with iron, AOB and anammox heme P460 proteins including cytochrome (cyt) P460 and hydroxylamine oxidoreductase (HAO) effect controlled, stepwise oxidation of NH2OH to nitric oxide (NO). Curiously, a recently characterized cyt P460 variant from the AOB Nitrosomonas sp. AL212 is able to form all intermediates of cyt P460 catalysis, but is nevertheless incompetent for NH2OH oxidation. We now show via site-directed mutagenesis, activity assays, spectroscopy, and structural biology that this lack of activity is attributable to the absence of a critical basic glutamate residue in the distal pocket above the heme P460 cofactor. This substitution is the only distinguishing characteristic of a protein that is otherwise effectively structurally and spectroscopically identical to an active variant. This highlights and reinforces a fundamental principal of metalloenzymology: metallocofactor inner-sphere geometric and electronic structures are in many cases insufficient for imbuing reactivity; a precisely defined outer coordination sphere contributed by the polypeptide matrix can be the key differentiator between a metalloenzyme and an unreactive metalloprotein.
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Affiliation(s)
- Meghan A Smith
- Department of Chemistry and Chemical Biology , Baker Laboratory , Cornell University , Ithaca , NY 14853 , USA .
| | - Sean H Majer
- Department of Chemistry and Chemical Biology , Baker Laboratory , Cornell University , Ithaca , NY 14853 , USA .
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology , Baker Laboratory , Cornell University , Ithaca , NY 14853 , USA .
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology , Baker Laboratory , Cornell University , Ithaca , NY 14853 , USA .
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10
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Atifi A, Mak PJ, Ryan MD. Proton-coupled reduction of an iron nitrosyl porphyrin in the protic ionic liquid nanodomain. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.10.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Rahman MH, Ryan MD. The use of RRDE voltammetry to study acid-base reactions in unbuffered solutions. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.05.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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12
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Rahman MH, Ryan MD. Insight into Solvent Coordination of an Iron Porphyrin Hydroxylamine Complex from Spectroscopy and DFT Calculations. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Md. Hafizur Rahman
- Chemistry Department Marquette University PO Box 1881 53201 Milwaukee WI USA
| | - Michael D. Ryan
- Chemistry Department Marquette University PO Box 1881 53201 Milwaukee WI USA
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13
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Rahman MH, Ryan MD. Redox and Spectroscopic Properties of Iron Porphyrin Nitroxyl in the Presence of Weak Acids. Inorg Chem 2017; 56:3302-3309. [DOI: 10.1021/acs.inorgchem.6b02665] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Md. Hafizur Rahman
- Marquette University Chemistry Department, PO Box 1881, Milwaukee, Wisconsin 53201, United States
| | - Michael D. Ryan
- Marquette University Chemistry Department, PO Box 1881, Milwaukee, Wisconsin 53201, United States
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14
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Kalita A, Kumar V, Mondal B. Nitric oxide reactivity of copper(II) complexes of bidentate amine ligands. Inorganica Chim Acta 2015. [DOI: 10.1016/j.ica.2015.02.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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Porter TR, Mayer JM. Radical Reactivity of the Fe(III)/(II) Tetramesitylporphyrin Couple: Hydrogen Atom Transfer, Oxyl Radical Dissociation, and Catalytic Disproportionation of a Hydroxylamine. Chem Sci 2014; 5:372-380. [PMID: 24729854 PMCID: PMC3981745 DOI: 10.1039/c3sc52055b] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The chemistry of low-valent iron porphyrin complexes with oxyl radical reagents has been explored. (Meso-tetramesityl porphyrinato) iron(III) hydroxide, (TMP)FeIII(OH) reacts with the hydroxylamine TEMPO-H (1-hydroxy-2,2,6,6-tetramethylpiperdine) to yield the ferrous porphyrin, (TMP)FeII, together with H2O and TEMPO. This reaction has a second order rate constant k1 = 76 ± 5 M-1 1 s-1 and likely occurs by concerted e-/H+ transfer. Hydrazines PhNHNHPh and PhNHNH2 similarly yield (TMP)FeII. A subsequent reaction between TEMPO (2,2,6,6-tetramethylpiperdinyl radical) and (TMP)FeII is observed to reversibly form the TEMPO-ligated ferric porphyrin, (TMP)FeIII(TEMPO). A combination of 1H NMR and optical spectroscopies were used to determine the thermodynamic parameters for TEMPO binding: K4 (25°C) = 535 ± 20 M-1, ΔH°4 = -7.0 ± 1.5 kcal mol-1, ΔS°4= -11 ± 5 cal mol-1 K-1, ΔG‡4(235K) = 21.3 ± 0.5 kcal mol-1, ΔG‡-4(235K) = 16.9 ± 0.5 kcal mol-1. The Fe-O bond is remarkably weak. The stable phenoxyl radical 2,4,6- t Bu3C6H2O• (ArO•) forms a stronger bond to (TMP)FeII to irreversibly make a similar FeIII(OR) complex. Both (TMP)FeII and (TMP)FeIII(OH) are catalysts for the disproportionation of excess TEMPO-H to TEMPO and TEMP-H (2,2,6,6-tetramethylpiperdine). The lack of reactivity between (TMP)FeII and the alkylated TEMPO-H analogue, TEMPO-CH3, suggests that the disproportionation involves a hydrogen atom transfer step. These results highlight the importance and versatility of the heme FeIII/II couple that is often overshadowed by its higher-valent counterparts.
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Affiliation(s)
| | - James M. Mayer
- Department of Chemistry, University of Washington, Seattle, WA
98195-1700
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16
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Goodrich LE, Roy S, Alp EE, Zhao J, Hu MY, Lehnert N. Electronic Structure and Biologically Relevant Reactivity of Low-Spin {FeNO}8 Porphyrin Model Complexes: New Insight from a Bis-Picket Fence Porphyrin. Inorg Chem 2013; 52:7766-80. [DOI: 10.1021/ic400977h] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lauren E. Goodrich
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109,
United States
| | - Saikat Roy
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109,
United States
| | - E. Ercan Alp
- Advanced
Photon Source, Argonne National Laboratory, Argonne, Illinois 60439,
United States
| | - Jiyong Zhao
- Advanced
Photon Source, Argonne National Laboratory, Argonne, Illinois 60439,
United States
| | - Michael Y. Hu
- Advanced
Photon Source, Argonne National Laboratory, Argonne, Illinois 60439,
United States
| | - Nicolai Lehnert
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109,
United States
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17
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McQuarters AB, Goodrich LE, Goodrich CM, Lehnert N. Disproportionation of O-Benzylhydroxylamine Catalyzed by a Ferric Bis-Picket Fence Porphyrin Complex. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201300125] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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19
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Gutiérrez MM, Olabe JA, Amorebieta VT. Nucleophilic Addition Reactions of the Nitroprusside Ion – The Case of
O
‐Methylhydroxylamine. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- María M. Gutiérrez
- Department of Chemistry, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes y Roca, Mar del Plata B7602AYL, Argentina, http://www.mdp.edu.ar
| | - José A. Olabe
- Department of Inorganic, Analytical and Physical Chemistry and INQUIMAE/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, Buenos Aires C1428EHA, Argentina
| | - Valentín T. Amorebieta
- Department of Chemistry, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes y Roca, Mar del Plata B7602AYL, Argentina, http://www.mdp.edu.ar
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20
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Sarma M, Kumar V, Kalita A, Deka RC, Mondal B. Nitric oxide reactivity of copper(ii) complexes of bidentate amine ligands: effect of chelate ring size on the stability of a [CuII–NO] intermediate. Dalton Trans 2012; 41:9543-52. [DOI: 10.1039/c2dt30721a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Kalita A, Kumar P, Deka RC, Mondal B. Role of Ligand to Control the Mechanism of Nitric Oxide Reduction of Copper(II) Complexes and Ligand Nitrosation. Inorg Chem 2011; 50:11868-76. [DOI: 10.1021/ic201582w] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Apurba Kalita
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati,
Assam 781039, India
| | - Pankaj Kumar
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati,
Assam 781039, India
| | - Ramesh C. Deka
- Department
of Chemical Sciences, Tezpur University, Napaam, Tezpur 784028, Assam, India
| | - Biplab Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati,
Assam 781039, India
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22
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Gutiérrez MM, Olabe JA, Amorebieta VT. Disproportionation of O-methylhydroxylamine catalyzed by aquapentacyanoferrate(II). Inorg Chem 2011; 50:8817-25. [PMID: 21859073 DOI: 10.1021/ic2007155] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aquapentacyanoferrate(II) ion, [Fe(II)(CN)(5)H(2)O](3-), catalyzes the disproportionation reaction of O-methylhydroxylamine, NH(2)OCH(3), with stoichiometry 3NH(2)OCH(3) → NH(3) + N(2) + 3CH(3)OH. Kinetic and spectroscopic evidence support an initial N coordination of NH(2)OCH(3) to [Fe(II)(CN)(5)H(2)O](3-) followed by a homolytic scission leading to radicals [Fe(II)(CN)(5)(•)NH(2)](3-) (a precursor of Fe(III) centers and bound NH(3)) and free methoxyl, CH(3)O(•), thus establishing a radical path leading to N-methoxyamino ((•)NHOCH(3)) and 1,2-dimethoxyhydrazine, (NHOCH(3))(2). The latter species is moderately stable and proposed to be the precursor of N(2) and most of the generated CH(3)OH. Intermediate [Fe(III)(CN)(5)L](2-) complexes (L = NH(3), H(2)O) form dinuclear cyano-bridged mixed-valent species, affording a catalytic substitution of the L ligands promoted by [Fe(II)(CN)(5)L](3-). Free or bound NH(2)OCH(3) may act as reductants of [Fe(III)(CN)(5)L](2-), thus regenerating active sites. At increasing concentrations of NH(2)OCH(3) a coordinated diazene species emerges, [Fe(II)(CN)(5)N(2)H(2)](3-), which is consumed by the oxidizing CH(3)O(•), giving N(2) and CH(3)OH. Another side reaction forms [Fe(II)(CN)(5)N(O)CH(3)](3-), an intermediate containing the nitrosomethane ligand, which is further oxidized to the nitroprusside ion, [Fe(II)(CN)(5)NO](2-). The latter is a final oxidation product with a significant conversion of the initial [Fe(II)(CN)(5)H(2)O](3-) complex. The side reaction partially blocks the Fe(II)-aqua active site, though complete inhibition is not achieved because the radical path evolves faster than the formation rates of the Fe(II)-NO(+) bonds.
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Affiliation(s)
- María M Gutiérrez
- Department of Chemistry, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes y Roca, Mar del Plata B7602AYL, Argentina
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23
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Munro OQ, Camp GL, Carlton L. Structural,
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Rh NMR and DFT Studies of a Bis(phosphane)Rh
III
–Porphyrin Derivative. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200800837] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Orde Q. Munro
- School of Chemistry, University of KwaZulu‐Natal, Private Bag X01, Scottsville, 3209, Pietermaritzburg, South Africa, Fax: +27‐33‐260‐5009
| | - Greville L. Camp
- School of Chemistry, University of KwaZulu‐Natal, Private Bag X01, Scottsville, 3209, Pietermaritzburg, South Africa, Fax: +27‐33‐260‐5009
| | - Laurence Carlton
- School of Chemistry, University of the Witwatersrand, P. O. Wits 2050, Johannesburg, South Africa, Fax: +27‐11‐717‐6749
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24
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Spectroscopic properties and cyclic voltammetry on a series of meso-tetra(p-alkylamidophenyl)porphyrin liquid crystals and their Mn complexes. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2008.01.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Belock CW, Cetin A, Barone NV, Ziegler CJ. Transition metal coordination chemistry ofN,N-bis(2-{pyrid-2-ylethyl})hydroxylamine. Inorg Chem 2008; 47:7114-20. [PMID: 18646844 DOI: 10.1021/ic702406n] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although directly relevant to metal mediated biological nitrification as well as the coordination chemistry of peroxide, the metal complexes of hydroxylamines and their functionalized variants remain largely unexplored. The chelating hydroxylamine ligand N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine can be readily generated via a solvent free reaction in high purity; however, the ligand is prone to decomposition which can hamper metal reaction. N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine forms stable complexes with chromium(III), manganese(II), nickel(II), and cadmium(II) ions, coordinating in a side-on mode in the case of chromium and via the nitrogen in the case of the latter three metal ions. The hydroxylamine ligand can also be reduced to form N,N-bis(2-{pyrid-2-ylethyl})amine upon exposure to a stoichiometric amount of the metal salts cobalt(II) nitrate, vanadium(III) chloride, and iron(II) chloride. In the reaction with cobalt nitrate, the reduced ligand then chelates to the metal to form [N,N-bis(2-{pyrid-2-ylethyl})amine]dinitrocobalt(II). Upon reaction with vanadium(III) chloride and iron(III) chloride, the reduced ligand is isolated as the protonated free base, resulting from a metal-mediated decomposition reaction.
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Affiliation(s)
- Christopher W Belock
- Department of Chemistry, Knight Chemical Laboratory, University of Akron, Akron, Ohio 44325-3601, USA
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26
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Kostera J, Youngblut MD, Slosarczyk JM, Pacheco AA. Kinetic and product distribution analysis of NO* reductase activity in Nitrosomonas europaea hydroxylamine oxidoreductase. J Biol Inorg Chem 2008; 13:1073-83. [PMID: 18553112 DOI: 10.1007/s00775-008-0393-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2007] [Accepted: 05/25/2008] [Indexed: 10/22/2022]
Abstract
Hydroxylamine oxidoreductase (HAO) from the ammonia-oxidizing bacterium Nitrosomonas europaea normally catalyzes the four-electron oxidation of hydroxylamine to nitrite, which is the second step in ammonia-dependent respiration. Here we show that, in the presence of methyl viologen monocation radical (MV(red)), HAO can catalyze the reduction of nitric oxide to ammonia. The process is analogous to that catalyzed by cytochrome c nitrite reductase, an enzyme found in some bacteria that use nitrite as a terminal electron acceptor during anaerobic respiration. The availability of a reduction pathway to ammonia is an important factor to consider when designing in vitro studies of HAO, and may also have some physiological relevance. The reduction of nitric oxide to ammonia proceeds in two kinetically distinct steps: nitric oxide is first reduced to hydroxylamine, and then hydroxylamine is reduced to ammonia at a tenfold slower rate. The second step was investigated independently in solutions initially containing hydroxylamine, MV(red), and HAO. Both steps show first-order dependence on nitric oxide and HAO concentrations, and zero-order dependence on MV(red) concentration. The rate constants governing each reduction step were found to have values of (4.7 +/- 0.3) x 10(5) and (2.06 +/- 0.04) x 10(4) M(-1) s(-1), respectively. A second reduction pathway, with second-order dependence on nitric oxide, may become available as the concentration of nitric oxide is increased. Such a pathway might lead to production of nitrous oxide. We estimate a maximum value of (1.5 +/- 0.05) x 10(10) M(-2) s(-1) for the rate constant of the alternative pathway, which is small and suggests that the pathway is not physiologically important.
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Affiliation(s)
- Joshua Kostera
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
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27
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Ford PC, Fernandez BO, Lim MD. Mechanisms of Reductive Nitrosylation in Iron and Copper Models Relevant to Biological Systems. Chem Rev 2005; 105:2439-55. [PMID: 15941218 DOI: 10.1021/cr0307289] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Peter C Ford
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, 93106-9510, USA.
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28
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OLABE JOSÉA. REDOX REACTIVITY OF COORDINATED LIGANDS IN PENTACYANO(L)FERRATE COMPLEXES. ADVANCES IN INORGANIC CHEMISTRY 2004. [DOI: 10.1016/s0898-8838(03)55002-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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29
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Affiliation(s)
- Jens K S Møller
- Food Chemistry, Department of Dairy and Food Science, Royal Veterinary and Agricultural University, Rolighedsvej 30, DK-1958 Frederiksberg C., Denmark
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30
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Liang JL, Huang JS, Zhou ZY, Cheung KK, Che CM. Interaction between dioxoruthenium(VI) porphyrins and hydroxylamines: coordination of N-substituted hydroxylamine to ruthenium and X-ray crystal structures of ruthenium complexes with a unidentate nitrosoarene ligand. Chemistry 2001; 7:2306-17. [PMID: 11446633 DOI: 10.1002/1521-3765(20010601)7:11<2306::aid-chem23060>3.0.co;2-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The interactions between dioxoruthenium(VI) porphyrins 1 with N-phenylhydroxylamine or unsubstituted hydroxylamine are described. Reaction of complexes 1 with excess PhNHOH leads to isolation of bis(nitrosobenzene)ruthenium(II) porphyrins 3 and mono(nitrosobenzene)ruthenium(II) porphyrins 4. Both the types of ruthenium complexes are characterized by 1H NMR, IR, and UV/Vis spectroscopy, and mass spectrometry. The X-ray structure determinations on [Ru(II)(TPP)(PhNO)2] (3a), [Ru(II)(2,6-Cl-TPP)(PhNO)2] (3e), and [Ru(II)(4-MeO-TPP)(PhNO)(PhNH2)] (4d) (TPP tetraarylporphyrin) disclose a unidentate nitrosoarene coordination in all these complexes, with Ru-N(PhNO) bond lengths of 2.003(3) (3a, average), 1.991(3) (3e, average), and 2.042(2) A (4d). In the case of 4d, the Ru-N(PhNH2) bond length is found to be 2.075(3) A. Mechanistic investigations reveal the formation of intermediates [Ru(II)(Por)(PhNO)(PhNHOH)] (5; Por=porphyrin), a ruthenium complex with N-substituted hydroxylamine ligand, in the "1 + PhNHOH" system. The Ru-NH(OH)Ph moiety in 5 undergoes no rapid exchange with free PhNHOH in solution at room temperature, as revealed by 1H NMR spectroscopy. Unlike the interaction between complexes 1 and PhNHOH, reaction of such complexes with NH2OH affords nitrosylruthenium(II) porphyrins [Ru(II)(Por)(NO)(OH)] (6).
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Affiliation(s)
- J L Liang
- Department of Chemistry, The University of Hong Kong.
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31
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Asirvatham S, Khan M, Nicholas K. Reductive nitrosylation of MoO2(dedtc)2 by hydroxylamine. Inorganica Chim Acta 2000. [DOI: 10.1016/s0020-1693(00)00131-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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32
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Marques HM, Munro OQ, Munro T, de Wet M, Vashi PR. Coordination of N-Donor Ligands by the Monomeric Ferric Porphyrin N-Acetylmicroperoxidase-8. Inorg Chem 1999. [DOI: 10.1021/ic981293o] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Helder M. Marques
- Centre for Molecular Design, Department of Chemistry, University of the Witwatersrand, P.O. Wits, 2050 Johannesburg, South Africa
| | - Orde Q. Munro
- Centre for Molecular Design, Department of Chemistry, University of the Witwatersrand, P.O. Wits, 2050 Johannesburg, South Africa
| | - Tracey Munro
- Centre for Molecular Design, Department of Chemistry, University of the Witwatersrand, P.O. Wits, 2050 Johannesburg, South Africa
| | - Marina de Wet
- Centre for Molecular Design, Department of Chemistry, University of the Witwatersrand, P.O. Wits, 2050 Johannesburg, South Africa
| | - Preeti R. Vashi
- Centre for Molecular Design, Department of Chemistry, University of the Witwatersrand, P.O. Wits, 2050 Johannesburg, South Africa
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33
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Taguchi F. New molecule-based catalyst to produce H2 by metallo-porphine dispersed into polymer membrane. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s1381-1169(98)00218-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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34
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Shi C, Anson FC. (5,10,15,20-Tetramethylporphyrinato)cobalt(II): A Remarkably Active Catalyst for the Electroreduction of O2 to H2O. Inorg Chem 1998. [DOI: 10.1021/ic971255p] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chunnian Shi
- Arthur Amos Noyes Laboratories, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Fred C. Anson
- Arthur Amos Noyes Laboratories, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
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