Abstract：
:EPR-based potentiometric titrations are a well-established method for determining the reduction potentials of cofactors in large and complex proteins with at least one EPR-active state. However, such titrations require large amounts of protein. Here, we report a new method that requires an order of magnitude less protein than previously described methods, and that provides EPR samples suitable for measurements at both X- and Q-band microwave frequencies. We demonstrate our method by determining the reduction potential of the terminal [4Fe-4S] cluster (N2) in the intramolecular electron-transfer relay in mammalian respiratory complex I. The value determined by our method, Em7=-158mV, is precise, reproducible, and consistent with previously reported values. Our small-volume potentiometric titration method will facilitate detailed investigations of EPR-active centres in non-abundant and refractory proteins that can only be prepared in small quantities.
journal_name
J Inorg Biochemjournal_title
Journal of inorganic biochemistryauthors
Wright JJ,Salvadori E,Bridges HR,Hirst J,Roessler MMdoi
10.1016/j.jinorgbio.2016.04.025subject
Has Abstractpub_date
2016-09-01 00:00:00pages
201-206eissn
0162-0134issn
1873-3344pii
S0162-0134(16)30111-8journal_volume
162pub_type
杂志文章abstract：:Reduced azurin reacts with the resting, oxidized cytochrome c peroxidase of Pseudomonas aeruginosa to yield time courses observed at 420 nm, which consist of the sum of two exponential processes. Each process exhibits a hyperbolic dependence of the observed rate constant on the reduced azurin concentration. The fracti...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(92)80055-z
更新日期：1992-10-01 00:00:00
abstract：:Measurements of binding of certain divalent cations to yeast apoenolase were made using a pH-meter, chromatography, a divalent cation electrode, and ultrafiltration. The binding of the activating metal ions Mg2+ and Co2+ and the nonactivator Ca2+ were studied as functions of the presence or absence of substrate/produc...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(83)85030-2
更新日期：1983-11-01 00:00:00
abstract：:In this paper, Bi2S3 nanospheres with size of 212nm were prepared by a simple hydrothermal process. The selectively enhanced antibacterial effects of Bi2S3 nanospheres with three classes of ineffective antibiotics, β-lactam (cefuroxime, CXM; cefotaxime, CTX and piperacillin, PIP), quinolone (ciprofloxacin, CIP) and am...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2016.12.005
更新日期：2017-03-01 00:00:00
abstract：:N-pyrimidino benzamide-2-carboxylic acid (NPBCA) and its Cu(II), Ni(II), Co(II), Zn(II), and Mn(II) chelates have been synthesized and characterized by using elemental analyses, molar conductance, molecular weight determination, magnetic moment, infrared, and electronic spectra. Antifungal activity of the synthesized ...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(91)80027-f
更新日期：1991-04-01 00:00:00
abstract：:The cyanobacterium Synechococcus sp. PCC 7002 produces a monomeric hemoglobin (GlbN) implicated in the detoxification of reactive nitrogen and oxygen species. GlbN contains a b heme, which can be modified under certain reducing conditions. The modified protein (GlbN-A) has one heme-histidine C-N linkage similar to the...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2017.09.018
更新日期：2017-12-01 00:00:00
abstract：:We have studied the electron paramagnetic resonance (epr) spectra of complexes of apo-yeast enolase with 65Cu+2 in the presence and absence of substrate and magnesium ion. An unusual epr spectrum with large g parallel, large g and A rhombicity and very narrow line-widths (10 G) is seen for the first two 65Cu+2 bound i...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/s0162-0134(00)80255-x
更新日期：1980-12-01 00:00:00
abstract：:To explore the correlating thermodynamic factors to the structural aspects that account for the stability of the RNA triplex, two functional Ru(II) complexes containing the same ancillary ligands and different intercalative ligands, [Ru(bpy)(2)(mip)](2+) (bpy=2,2'-bipyridine, mip=2'-(3",4"-methylene-dioxyphenyl)imidaz...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2012.11.009
更新日期：2013-03-01 00:00:00
abstract：:The structural spectroscopic, and thermal properties of a complex of sulfacetamide (Hsacm) with Cu(II) have been investigated. The complex [Cu(Hsacm)2(NO3)2] crystallizes in the monoclinic system, space group P2(1)/n. The cell dimensions are a = 7.696(7) A, b = 8.017(7) A, c = 19.230(10), beta = 110.80(1) degree, V = ...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(94)85026-7
更新日期：1994-02-01 00:00:00
abstract：:A study has been performed of the kinetics and equilibria involved in complex formation between the macrocyclic polyamine 2,5,8,11-tetraaza[12]-[12](2,9)[1,10]-phenanthrolinophane (Neotrien) and Cu(II) in acidic aqueous solution and ionic strength 0.5 M (NaCl), by means of the stopped-flow method and UV spectrophotome...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2003.08.010
更新日期：2004-01-01 00:00:00
abstract：:Imidazole glycerol phosphate dehydratase (IGPD) catalyses the dehydration of imidazole glycerol phosphate to imidazole acetol phosphate, an important late step in the biosynthesis of histidine. IGPD, isolated as a low molecular weight and inactive apo-form, assembles with specific divalent metal cations to form a cata...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章,评审
doi：10.1016/s0162-0134(00)00025-8
更新日期：2000-05-30 00:00:00
abstract：:The reaction of hydrogen peroxide and certain aromatic aldehydes with cytochrome P450BM3-F87G results in the covalent modification of the heme cofactor of this monooxygenase. Analysis of the resulting heme by electronic absorption spectrophotometry indicates that the reaction in the BM3 isoform is analogous to that in...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/s0162-0134(00)00098-2
更新日期：2000-08-31 00:00:00
abstract：:The study aimed to develop simple assays to study aluminium-ligand interactions in natural/biological systems where equilibrium is rarely reached and thus where the initial seconds or hours of interactions are important. The immediate and non-equilibrium precipitation of aluminium hydroxide, in aqueous solution at neu...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/s0162-0134(01)00311-7
更新日期：2001-11-01 00:00:00
abstract：:The metallodrug chloridotetrakis(ibuprofenato)diruthenium(II,III) ([Ru2(Ibp)4Cl] or RuIbpCl (1), Ibp=carboxylate anion derived from the non-steroidal anti-inflammatory drug ibuprofen) has shown promising results in vitro and in vivo, which point to its potential as an inhibitor of glioma tumour growth in vivo. In orde...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2016.10.003
更新日期：2016-12-01 00:00:00
abstract：:The effect of inositol hexakisphosphate (IHP) on the spectroscopic (EPR and absorbance) properties of the nitric oxide derivative of ferrous naturally glycated human hemoglobin HbA1c (HbA1cNO) has been investigated quantitatively. The results obtained show that 1) both in the absence and presence of IHP, the EPR and a...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(88)85014-1
更新日期：1988-09-01 00:00:00
abstract：:The energy diagram for the catalytic cycle of dioxygen evolution in photosystem II has been recomputed using a slightly different model than the one used previously, since the results showed an erroneous trend in the critical region from S(2) to S(3). By replacing the bicarbonate ligand, which was bridging between cal...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2006.02.007
更新日期：2006-05-01 00:00:00
abstract：:The present Mössbauer spectroscopic studies of isolated bacterioferritin and whole cells of Pseudomonas aeruginosa have shown that the iron core of bacterioferritin is not altered on isolation. These studies have also shown that the bacterioferritin core is typically 85% oxidized within the cell and may contain a sign...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(91)80046-k
更新日期：1991-09-01 00:00:00
abstract：:A series of new iron(III) and copper(II) complexes of bovine serum transferrin (BTf), with carbonate and/or oxalate as the synergistic anion, are presented. The complexes [Fe(2)(CO(3))(2)BTf], [Fe(2)(C(2)O(4))(2)BTf], [Cu(2)(CO(3))(2)BTf] and [Cu(C(2)O(4))BTf] were prepared by standard titrimetric techniques. The oxal...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2003.10.009
更新日期：2004-02-01 00:00:00
abstract：:Previous studies of the interaction of the haem undecapeptide (MP-11) with lipidated human serum albumin in aqueous solution have been extended to a range of MeOH/H2O solution compositions. It is demonstrated that the kinetic mechanism for the interaction does not change from a simple second- and first-order reversibl...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/0162-0134(93)80009-x
更新日期：1993-04-01 00:00:00
abstract：:Lathyrus cicera copper amine oxidase (LCAO) rapidly formed the typical Cu(I)-TPQ semiquinone UV-visible spectrum, identical to that formed by other substrates, upon O(2) exhaustion by turnover with excess tryptamine. A new band at 630 nm formed more slowly, with intensity dependent on aldehyde and H(2)O(2) concentrati...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2012.01.002
更新日期：2012-04-01 00:00:00
abstract：:The new cyclic tetrapeptide c(HGHK) was synthesised in the solid phase and its complexes with copper(II) were studied in aqueous solution at various pH values by means of potentiometric and spectroscopic methods (UV, EPR, CD). Six mononuclear coordination species were clearly identified within the pH range 3-11. Spect...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2004.09.007
更新日期：2004-12-01 00:00:00
abstract：:Uranium is an element belonging to the actinide series. It is ubiquitous in rock, soil, and water. Uranium is found in the ecosystem due to mining and milling industrial activities and processing to nuclear fuel, but also to the extensive use of phosphate fertilizers. Understanding uranium binding in vivo is critical,...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章,评审
doi：10.1016/j.jinorgbio.2019.110936
更新日期：2020-02-01 00:00:00
abstract：:Interaction of Delta,Delta- and Lambda,Lambda-bis-Ru(II) complexes with native DNA was investigated by isotropic absorption and polarized spectroscopy including circular and linear dichroism (CD and LD). Despite the steric hindrance originating from its four bulky phenanthroline ligands at both ends of the molecule, t...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2008.06.012
更新日期：2008-10-01 00:00:00
abstract：: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 transferrin. We have determined the redox potentials for a series of T...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2010.04.004
更新日期：2010-09-01 00:00:00
abstract：:Plastocyanin (PC) from poplar leaves is present in two isoforms, PCa and PCb, which differ in sequence by amino acid replacements at locations remote from the copper center and simultaneously act in the photosynthetic electron-transport chain. We describe ultra-high resolution structures of PCa and high-resolution str...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2012.07.015
更新日期：2012-10-01 00:00:00
abstract：:The coordination modes of Cu(II) to alpha-casein (90-95) and alpha-casein (90-96) peptides with opioid activity isolated from pepsin hydrolisates of alpha-casein were investigated by means of electron paramagnetic resonance, absorption, and circular dichroism spectroscopy and potentiometry. The results allow the ident...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/s0162-0134(96)00147-x
更新日期：1997-04-01 00:00:00
abstract：:Aiming at obtaining new copper complexes with good cytotoxicity against cancer cells, triphenylphosphine (TPP) was introduced to obtain insight into the influence of the co-ligands. In this paper, two copper complexes, Cu(2-pbmq)(CH3OH)Br2 (1) and [Cu(2-pbmq)(TPP)Br]2 (2) were designed, synthesized, and characterized ...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2020.111102
更新日期：2020-09-01 00:00:00
abstract：:Copper based nanoparticles (Cu-based NPs) of different compositions and sizes have been hydrothermally synthesized by varying the reaction time in the presence of the biocompatible surfactants polyoxyethylene (20) sorbitan laurate (Tween 20) and polyethylene glycol 8000 (PEG 8000). Effective control of the above synth...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2013.12.009
更新日期：2014-04-01 00:00:00
abstract：:New heteroditopic, bi- and multidentate imino- and aminophosphine ligands were synthesised and complexed to [AuCl(THT)] (THT=tetrahydrothiophene). X-ray crystallography confirmed Schiff base formation in three products, the successful reduction of the imino-group to the sp(3)-hybridised amine in several instances, and...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2015.01.014
更新日期：2015-04-01 00:00:00
abstract：:In this paper we present the studies on coordination abilities of two short-chain analogues of somatostatin with free N-terminal and protected amino group towards copper (II) ions. The octreotide is the most popular analogue of the somatostatin (peptide hormone) used in medicine. Somatostatin analogues are used in dia...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2012.08.023
更新日期：2012-12-01 00:00:00
abstract：:An in vitro and in vivo study of some copper chelating anti-inflammatory agents for alleviation of inflammation associated with rheumatoid arthritis (RA) has been conducted. Two copper chelating agents, N(1)-(2-aminoethyl)-N(2)-(pyridin-2-ylmethyl)ethane-1,2-diamine ([555-N]) and N-(2-(2-aminoethylamino)ethyl)picolina...
journal_title：Journal of inorganic biochemistry
pub_type： 杂志文章
doi：10.1016/j.jinorgbio.2006.09.006
更新日期：2007-01-01 00:00:00
