Insight on the interaction of an agmatinase-like protein with Mn(2+) activator ions.
, López V, Schenk G, Uribe E Abstract Agmatinase is an enzyme that catalyzes the hydrolysis of agmatine, a compound that is associated with numerous functions in the brain of mammalian organisms such as neurotransmitter, anticonvulsant, antinociceptive, anxiolytic and antidepressant-like actions. To date the only characterized agmatinases with significant enzymatic activity were extracted from bacterial organisms. These agmatinases are closely related to another ureahydrolase, arginase; both have binuclear Mn(2+) centers in their active sites. An agmatinase-like protein (ALP) from rat brain was identified t...
Source: Journal of Inorganic Biochemistry - January 23, 2015 Category: Biochemistry Authors: Quiñones M, Cofre J, Benítez J, García D, Romero N, González A, Carvajal N, García M, López V, Schenk G, Uribe E Tags: J Inorg Biochem Source Type: research

Controlling diabetes by chromium complexes: The role of the ligands.
Abstract Diabetes, particularly type II diabetes, is a severe disease condition which affects human health worldwide, with a dramatically increasing trend in Asian countries including China. Currently, no efficient drugs other than those with observable side effects are available. Chromium complexes, with the most known representative chromium picolinate, have been listed as one of most attractive health supplements to attenuate this disease condition in western countries. Recent efforts have been made to develop new chromium complexes with novel ligands. Although fair amounts of reviews have been published to emp...
Source: Journal of Inorganic Biochemistry - January 19, 2015 Category: Biochemistry Authors: Peng M, Yang X Tags: J Inorg Biochem Source Type: research

Quercetin encapsulation in modified silica nanoparticles: potential use against Cu(II)-induced oxidative stress in neurodegeneration.
Abstract Neurodegenerative diseases entail deeply complex processes, intimately associated with progressive brain damage reflecting cellular demise. Biochemical reactivity linked to such processes in Alzheimer's disease involves, among others, metal-induced oxidative stress contributing to neuronal cell death. Prominent among redox active metals inducing oxidative stress is Cu(II). Poised to develop molecular technology counteracting oxidative stress, efforts were launched to prepare bioactive hybrid nanoparticles, capable of working as host-carriers of potent antioxidants, such as the natural flavonoid quercetin....
Source: Journal of Inorganic Biochemistry - January 10, 2015 Category: Biochemistry Authors: Nday CM, Halevas E, Jackson GE, Salifoglou A Tags: J Inorg Biochem Source Type: research

Sulfur and selenium antioxidants: Challenging radical scavenging mechanisms and developing structure-activity relationships based on metal binding.
Abstract Because sulfur and selenium antioxidants can prevent oxidative damage, numerous animal and clinical trials have investigated the ability of these compounds to prevent the oxidative stress that is an underlying cause of cardiovascular disease, Alzheimer's disease, and cancer, among others. One of the most common sources of oxidative damage is metal-generated hydroxyl radical; however, very little research has focused on determining the metal-binding abilities and structural attributes that affect oxidative damage prevention by sulfur and selenium compounds. In this review, we describe our ongoing investiga...
Source: Journal of Inorganic Biochemistry - December 29, 2014 Category: Biochemistry Authors: Zimmerman MT, Bayse CA, Ramoutar RR, Brumaghim JL Tags: J Inorg Biochem Source Type: research

Characterization and biotransformation in the plasma and red blood cells of V(IV)O(2+) complexes formed by ceftriaxone.
era G, Garribba E Abstract The coordination mode and geometry in aqueous solution of oxidovanadium(IV) complexes formed by a third-generation cephalosporin, ceftriaxone (H3cef), were studied by spectroscopic (EPR, electron paramagnetic resonance), pH-potentiometric and computational (DFT, density functional theory) methods. The behavior of the model systems containing 6-hydroxy-2-methyl-3-thioxo-3,4-dihydro-1,2,4-triazine-5(2H)-one (H2hmtdt) and 3-benzylthio-6-hydroxy-2-methyl-1,2,4-triazine-5(2H)-one (Hbhmt) was examined for comparison. The stability of the tautomers of ceftriaxone and 6-hydroxy-2-methyl-3-thioxo...
Source: Journal of Inorganic Biochemistry - December 29, 2014 Category: Biochemistry Authors: Sanna D, Fabbri D, Serra M, Buglyó P, Bíró L, Ugone V, Micera G, Garribba E Tags: J Inorg Biochem Source Type: research

pH-metric chemical speciation modeling and studies of in vitro antidiabetic effects of bis[(imidazolyl)carboxylato]oxidovanadium(IV) complexes.
Abstract A range of bidentate N,O-donor ligands of the imidazolyl-carboxylate moiety, which partially mimic naturally occurring bioligands, were prepared and reacted with the oxidovanadium(IV) ion to form the corresponding bis-coordinated oxidovanadium(IV) complexes. The aqueous pH-metric chemical speciation was investigated using glass electrode potentiometry, which allowed for the determination of protonation and stability constants of the ligands and complexes, respectively. The species distribution diagrams generated from this information gave evidence that the bis[(imidazolyl)carboxylato]oxovanadium(IV) compl...
Source: Journal of Inorganic Biochemistry - December 27, 2014 Category: Biochemistry Authors: Gundhla IZ, Walmsley RS, Ugirinema V, Mnonopi NO, Hosten E, Betz R, Frost CL, Tshentu ZR Tags: J Inorg Biochem Source Type: research

Evaluation of the cell cytotoxicity and DNA/BSA binding and cleavage activity of some dioxidovanadium(V) complexes containing aroylhydrazones.
Abstract Three dioxidovanadium(V) complexes [VO2L(1-3)] (1-3) [HL(1)=1-napthoyl hydrazone of 2-acetyl pyridine, HL(2)=2-furoyl hydrazone of 2-acetyl pyridine and H2L(3)=isonicotinoyl hydrazone of 2-hydroxy benzaldehyde] have been reported. All the complexes were characterized by various spectroscopy (IR, UV-visible and NMR) and the molecular structures of 1 and 2 were characterized by single crystal X-ray diffraction technique. Structural report established five-coordinate geometries, distorted toward square pyramidal for each of 1 and 2, based on a tridentate -O,N,N coordinating anion and two oxido-O atoms. The e...
Source: Journal of Inorganic Biochemistry - December 27, 2014 Category: Biochemistry Authors: Dash SP, Panda AK, Pasayat S, Majumder S, Biswas A, Kaminsky W, Mukhopadhyay S, Bhutia SK, Dinda R Tags: J Inorg Biochem Source Type: research

Prospects of molybdenum and rhenium octahedral cluster complexes as X-ray contrast agents.
Abstract Investigation of new X-ray contrast media for radiography is an important field of science since discovering of X-rays in 1895. Despite the wide diversity of available X-ray contrast media the toxicity, especially nephrotoxicity, is still a big problem to be solved. The octahedral metal-cluster complexes of the general formula [{M6Q8}L6] can be considered as quite promising candidates for the role of new radiocontrast media due to the high local concentration of heavy elements, high tuning ability of ligand environment and low toxicity. To exemplify this, the X-ray computed tomography experiments for the ...
Source: Journal of Inorganic Biochemistry - December 27, 2014 Category: Biochemistry Authors: Krasilnikova AA, Shestopalov MA, Brylev KA, Kirilova IA, Khripko OP, Zubareva KE, Khripko YI, Podorognaya VT, Shestopalova LV, Fedorov VE, Mironov YV Tags: J Inorg Biochem Source Type: research

Enhancing the copper(II) complexes cytotoxicity to cancer cells through bound to human serum albumin.
Abstract We use Schiff-base salicylaldehyde benzoylhydrazone (HL) as the ligand for copper(II), resulting in the complexes [CuCl(L)]·H2O (C1), [CuNO3(L)]·H2O (C2) and [CuBr(L)]2 (C3). We characterize the Cu(II) compounds' interactions with human serum albumin (HSA) using fluorescence spectroscopy and molecular docking. These studies revealed that Cu(II) compounds propensity bound to IIA subdomain of HSA possible by hydrophobic interactions and hydrogen bond. Cu(II) compounds produce intracellular reactive oxygen species (ROS) in cancer cells. Complexes of HSA and copper(II) compounds enhance about 2-...
Source: Journal of Inorganic Biochemistry - December 19, 2014 Category: Biochemistry Authors: Gou Y, Zhang Y, Qi J, Zhou Z, Yang F, Liang H Tags: J Inorg Biochem Source Type: research

Ferric microperoxidase-11 catalyzes peroxynitrite isomerization.
Abstract Microperoxidase-11 (MP11) is an undecapeptide derived from horse heart cytochrome c offering the possibility to study the reactivity of the heme group relatively unshielded by the protein. Here, the peroxynitrite isomerization to NO3(-) catalyzed by ferric MP11 (MP11-Fe(III)) is reported. Data were obtained between pH3.6 and 8.1, at 20.0°C. The value of the second-order rate constant (kon) for peroxynitrite isomerization to NO3(-) by MP11-Fe(III) decreases from (1.1±0.1)×10(5)M(-1)s(-1), at pH3.6, to (6.1±0.6)×10(3)M(-1)s(-1), at pH8.1. The pH dependence of kon (pKa=6.9) sugg...
Source: Journal of Inorganic Biochemistry - December 19, 2014 Category: Biochemistry Authors: Ascenzi P, Leboffe L, Santucci R, Coletta M Tags: J Inorg Biochem Source Type: research

Aqueous vanadium ion dynamics relevant to bioinorganic chemistry: A review.
Abstract Aqueous solutions of the four highest vanadium oxidation states exhibit four diverse colors, which only hint at the diverse reactions that these ions can undergo. Cationic vanadium ions form complexes with ligands; anionic vanadium ions form complexes with ligands and self-react to form isopolyanions. All vanadium species undergo oxidation-reduction reactions. With a few exceptions, elucidation of the dynamics of these reactions awaited the development of fast reaction techniques before the kinetics of elementary ligation, condensation, reduction, and oxidation of the aqueous vanadium ions could be invest...
Source: Journal of Inorganic Biochemistry - December 15, 2014 Category: Biochemistry Authors: Kustin K Tags: J Inorg Biochem Source Type: research

Structural determination of Cu and Fe-Citrate complexes: theoretical investigation and analysis by ESI-MS.
Abstract The combined use of ESI-MS (electrospray ionization-mass spectrometry) and theoretical calculations for the determination of citrate:metal (metal=Cu and Fe) structures are reported. Mass spectrometry allowed to determine the stoichiometry 1:1 and 2:1 of the complexes, corroborating the theoretical calculations. The species found in the ratio 2:1 had their calculated structures readjusted, from what was originally simulated, since the deprotonation of citric acid differed from what was before simulated. The thermodynamic stability (ΔH(aq.)(0)) of the complexes optimized at the B3LYP/LANL2DZ level was...
Source: Journal of Inorganic Biochemistry - December 15, 2014 Category: Biochemistry Authors: Bertoli AC, Carvalho R, Freitas MP, Ramalho TC, Mancini DT, Oliveira MC, de Varennes A, Dias A Tags: J Inorg Biochem Source Type: research

Binding of trivalent chromium to serum transferrin is sufficiently rapid to be physiologically relevant.
Abstract Transferrin, the major iron transport protein in the blood, also transports trivalent chromium in vivo. Recent in vitro studies have, however, suggested that the binding of chromic ions to apotransferrin is too slow to be biologically relevant. Nevertheless, the in vitro studies have generally failed to adequately take physiological bicarbonate concentrations into account. In aqueous buffer (with ambient (bi)carbonate concentrations), the binding of chromium to transferrin is too slow to be physiologically relevant, taking days to reach equilibrium with the protein's associated conformational changes. How...
Source: Journal of Inorganic Biochemistry - December 11, 2014 Category: Biochemistry Authors: Deng G, Wu K, Cruce AA, Bowman MK, Vincent JB Tags: J Inorg Biochem Source Type: research

Effect of ancillary ligands on the interaction of ruthenium(II) complexes with the triplex RNA poly(U)·poly(A)*poly(U).
Effect of ancillary ligands on the interaction of ruthenium(II) complexes with the triplex RNA poly(U)·poly(A)*poly(U). J Inorg Biochem. 2014 Dec 11;143C:56-63 Authors: Li J, Sun Y, Xie L, He X, Tan L Abstract Two new Ru(II) complexes with 1,8-naphthalimide group, [Ru(phen)2(pnip)](2+) (Ru1; phen=1,10-phenanthroline, pnip=2-[N-(p-phenyl)-1,8-napthalimide]imidazo[4',5'-f][1,10]phenanthroline) and [Ru(bpy)2(pnip)](2+) (Ru2; bpy=2,2'-bipyridine), have been synthesized and characterized. The interactions of Ru1 and Ru2 with the triplex RNA poly(U)•poly(A)*poly(U) (where • denotes the Wats...
Source: Journal of Inorganic Biochemistry - December 11, 2014 Category: Biochemistry Authors: Li J, Sun Y, Xie L, He X, Tan L Tags: J Inorg Biochem Source Type: research

Structural biology of the lanthanides-mining rare earths in the Protein Data Bank.
Abstract With its about 100,000 three-dimensional structures, the Protein Data Bank is a copious source of information: it contains also some hundreds of structures of macromolecules complexed with lanthanide cations, which are examined here. These cations, which are found in a wide variety of protein types, were introduced to determine the structures, by exploiting their anomalous dispersion (in crystallographic studies, where they are also used as crystallization additives) or the paramagnetic pseudocontact shifts (in NMR analyses). The coordination numbers in the first coordination sphere are very variable, tho...
Source: Journal of Inorganic Biochemistry - December 11, 2014 Category: Biochemistry Authors: Djinovic-Carugo K, Carugo O Tags: J Inorg Biochem Source Type: research

Cu(II)-dipeptide complexes of 2-(4'-thiazolyl)benzimidazole: Synthesis, DNA oxidative damage, antioxidant and in vitro antitumor activity.
Abstract Two new Cu(II)-dipeptide complexes of 2-(4'-thiazolyl)benzimidazole, [Cu(Gly-Gly)(TBZ)(Cl)]·4H2O (1) and [Cu(Gly-l-Leu)(TBZ)(Cl)]·H2O (2) (Gly-Gly=glycyl-glycine anion, Gly-l-Leu=glycyl-l-leucine anion and TBZ=2-(4'-thiazolyl)benzimidazole) have been synthesized and characterized by elemental analyses, molar conductance measurements and spectroscopy methods (IR, UV-visible, electrospray ionization mass spectra (ESI-MS) and EPR). The DNA binding and cleavage properties of the complexes monitored by multi-spectroscopic techniques (UV absorption, fluorescence and circular dichroism), viscosity ...
Source: Journal of Inorganic Biochemistry - December 10, 2014 Category: Biochemistry Authors: Fu X, Zhang J, Liu D, Gan Q, Gao H, Mao Z, Le X Tags: J Inorg Biochem Source Type: research

Stereospecific ligands and their complexes. XXII. Synthesis and antitumor activity of palladium(II) complexes with some esters of (S,S)-ethylenediamine-N,N'-di-(2,2'-di(4-hydroxy-benzyl))-acetic acid.
Abstract Four new ligands and their palladium(II) complexes of general formula R2-S,S-eddtyr (L1-L4) and [PdCl2(R2-S,S-eddtyr)] (C1-C4) (R=ethyl, n-propyl, n-butyl and n-pentyl; S,S-eddtyr·2HCl=ethylenediamine-N,N'-di-(2,2'-di(4-hydroxy-benzyl))-acetic acid dihydrochloride have been synthesized and characterized by microanalysis, infrared, (1)H and (13)C NMR spectroscopy. Cytotoxicity for ligands and complexes on two different cell lines (human breast cancer, MDA-MB-231 and human lung cancer, A549 cell lines) and human chronic lymphocytic leukemia cells (CLL) was investigated using MTT (3-[4,5-dimethylthiaz...
Source: Journal of Inorganic Biochemistry - December 10, 2014 Category: Biochemistry Authors: Stojković DL, Jevtić VV, Radić GP, Todorović DV, Petrović M, Zarić M, Nikolić I, Baskić D, Trifunović SR Tags: J Inorg Biochem Source Type: research

The reaction of dichlorodiammineplatinum(II), [PtCl2(NH3)2], isomers with zinc fingers.
Abstract The interaction of cis-DDP and trans-DDP (DDP=[PtCl2(NH3)2]) with the C-terminal zinc finger (ZF2) of the HIVNCp7 nucleocapsid protein was investigated by fluorescence, circular dichroism, mass spectrometry, and {(1)H, (15)N} HSQC (heteronuclear single quantum coherence) NMR spectroscopy. The rate of reaction differed significantly for the two compounds, with the trans isomer reacting in a significantly faster manner, as expected. {(1)H, (15)N} HSQC NMR of (15)N-labeled compounds with the ZF2 showed the appearance of several new (15)N peaks, consistent with sulfur binding and formation of Pt-S species. Ma...
Source: Journal of Inorganic Biochemistry - December 10, 2014 Category: Biochemistry Authors: Tsotsoros SD, Qu Y, Farrell NP Tags: J Inorg Biochem Source Type: research

Photoinduced DNA damage and cytotoxicity by a triphenylamine-modified platinum-diimine complex.
Abstract Many planar photosensitizers tend to self-aggregate via van der Waals interactions between π-conjugated systems. The self-aggregation of the photosensitizer may reduce the efficiency of the photosensitizer to generate singlet oxygen, thereby diminishing its photodynamic activity. Efforts have been made to improve the photodynamic activity of bis-(o-diiminobenzosemiquinonato)platinum(II) which has planar geometry by the introduction of the sterically hindered triphenylamine moiety into the ligand. Herein we report the photoinduced DNA damage and cytotoxicity by a triphenylamine-modified platinum-diimine...
Source: Journal of Inorganic Biochemistry - December 9, 2014 Category: Biochemistry Authors: Zhang Z, Dai R, Ma J, Wang S, Wei X, Wang H Tags: J Inorg Biochem Source Type: research

Hydrogen generation: Aromatic dithiolate-bridged metal carbonyl complexes as hydrogenase catalytic site models.
Abstract The design, syntheses and characteristics of metal carbonyl complexes with aromatic dithiolate linkers reported as bioinspired hydrogenase catalytic site models are described and reviewed. Among these the complexes capable of hydrogen generation have been discussed in detail. Comparisons have been made with carbonyl complexes having alkyl dithiolates as linkers between metal centers. PMID: 25528677 [PubMed - as supplied by publisher] (Source: Journal of Inorganic Biochemistry)
Source: Journal of Inorganic Biochemistry - December 3, 2014 Category: Biochemistry Authors: Pandey IK, Natarajan M, Kaur-Ghumaan S Tags: J Inorg Biochem Source Type: research

Chelating ability and biological activity of hesperetin Schiff base.
Abstract Hydrazone hesperetin Schiff base (HHSB) - N-[(±)-[5,7-dihydroxy-2-(3-hydroxy-4-methoxy-phenyl)chroman-4-ylidene]amino]benzamide has been synthesized and its crystal structure was determined. This compound was used for the formation of Cu(II) complexes in solid state and in solution which were characterized using different spectroscopic methods. The analyses of potentiometric titration curves revealed that monomeric and dimeric complexes of Cu(II) are formed above pH7. The ESI-MS (electrospray ionization-mass spectrometry) spectra confirmed their formation. The EPR and UV-visible spectra evidenced t...
Source: Journal of Inorganic Biochemistry - November 28, 2014 Category: Biochemistry Authors: Lodyga-Chruscinska E, Symonowicz M, Sykula A, Bujacz A, Garribba E, Rowinska-Zyrek M, Oldziej S, Klewicka E, Janicka M, Krolewska K, Cieslak M, Brodowska K, Chruscinski L Tags: J Inorg Biochem Source Type: research

Structural and theoretical studies on rhodium and iridium complexes with 5-nitrosopyrimidines. Effects on the proteolytic regulatory enzymes of the renin-angiotensin system in human tumoral brain cells.
Martínez-Martos JM, Moreno-Carretero MN Abstract The reactions of [RhCl(CO)(PPh3)2], [RhCl(CO)2]2 and [IrCl(CO)(PPh3)2] with different 5-nitrosopyrimidines afforded sixteen complexes which have been structurally characterized by elemental analysis, IR and NMR ((1)H and (13)C) spectral methods and luminescence spectroscopy. The crystal and molecular structures of [Rh(III)Cl(VIOH-1)2(PPh3)], [Rh(III)Cl(DVIOH-1)2(PPh3)] and [Rh(II)(DVIOH-1)2(PPh3)2] have been established from single crystal x-ray structure analyses. The three complexes are six-coordinated with both violurato ligands into an equatorial N5,O4-b...
Source: Journal of Inorganic Biochemistry - November 22, 2014 Category: Biochemistry Authors: Illán-Cabeza NA, Jiménez-Pulido SB, Ramírez-Expósito MJ, García-García AR, Peña-Ruiz T, Martínez-Martos JM, Moreno-Carretero MN Tags: J Inorg Biochem Source Type: research

Synthesis, crystal and solution structures and antimicrobial screening of palladium(II) complexes with 2-(phenylselanylmethyl)oxolane and 2-(phenylselanylmethyl)oxane as ligands.
Abstract Two novel Pd(II) complexes with 2-(phenylselanylmethyl)oxolane and 2-(phenylselanylmethyl)oxane as ligands were synthesized. The crystal and molecular structure of the complexes has been determined by single crystal X-ray diffraction. It turned out for both complexes that the two ligands are coordinated to Pd via Se atoms in a trans-fashion and the other two trans-positions are occupied by Cl ions. Detailed 1D- and 2D-NMR analyses revealed the existence of equilibrating trans-diastereomeric species differing in the configuration at four chiral centers (selenium and carbon) in the solution of the complexes...
Source: Journal of Inorganic Biochemistry - November 20, 2014 Category: Biochemistry Authors: Bugarčić ZM, Divac VM, Kostić MD, Janković NZ, Heinemann FW, Radulović NS, Stojanović-Radić ZZ Tags: J Inorg Biochem Source Type: research

Mn(II) complexes of scorpiand-like ligands. A model for the MnSOD active centre with high in vitro and in vivo activity.
ntilde;a A, García-España E Abstract Manganese complexes of polyamines consisting of an aza-pyridinophane macrocyclic core functionalised with side chains containing quinoline or pyridine units have been characterised by a variety of solution techniques and single crystal x-ray diffraction. Some of these compounds have proved to display interesting antioxidant capabilities in vitro and in vivo in prokaryotic (bacteria) and eukaryotic (yeast and fish embryo) organisms. In particular, the Mn complex of the ligand containing a 4-quinoline group in its side arm which, as it happens in the MnSOD enzymes, ...
Source: Journal of Inorganic Biochemistry - November 15, 2014 Category: Biochemistry Authors: Clares MP, Serena C, Blasco S, Nebot A, Del Castillo L, Soriano C, Domènech A, Sánchez-Sánchez AV, Soler-Calero L, Mullor JL, García-España A, García-España E Tags: J Inorg Biochem Source Type: research

XAS examination of glutathione-cobalt complexes in solution.
Abstract In the present work, we have investigated the coordination modes of cobalt with glutathione (γ-l-glutamyl-l-cysteinyl-glycine, GSH). A systematic study of cobalt-GSH complexes at basic and neutral pH has been undertaken with a multi-spectroscopic approach combined with quantum chemistry calculations. XAS (x-ray absorption spectroscopy) has been performed at the cobalt K edge in order to shed light into the cation coordination sphere and formal oxidation states. XANES (x-ray absorption near edge structure) enabled to show that in basic and neutral media, cobalt oxidation state is equal to +III and +I...
Source: Journal of Inorganic Biochemistry - November 1, 2014 Category: Biochemistry Authors: Bresson C, Spezia R, Solari PL, Jankowski CK, Den Auwer C Tags: J Inorg Biochem Source Type: research

Silver(I) compounds of the anti-inflammatory agents salicylic acid and p-hydroxyl-benzoic acid which modulate cell function.
Abstract Silver nitrate reacts with salicylic acid (salH2) or p-hydroxy-benzoic acid (p-HbzaH2) and equimolar amount of NaOH to yield a white precipitations which are then treated with tri(p-tolyl)phosphine (tptp) or tri(m-tolyl)phosphine (tmtp) to yield the complexes [Ag(tptp)2(salH)] (1), [Ag(tptp)2(p-Hbza)] (2) and [Ag(tmtp)2(salH)] (3). Complexes 1 and 3 are also obtained when aspirin (aspH) is used. The acetic ester of salicylic acid is hydrolyzed to form the complexes 1 and 3. However, when aspirin and tptp are used, a mixture of products was obtained which contains both 1 and an ionic complex of formula {[A...
Source: Journal of Inorganic Biochemistry - October 27, 2014 Category: Biochemistry Authors: Banti CN, Giannoulis AD, Kourkoumelis N, Owczarzak AM, Kubicki M, Hadjikakou SK Tags: J Inorg Biochem Source Type: research

Iron-salophen complexes involving azole-derived ligands: A new group of compounds with high-level and broad-spectrum in vitro antitumor activity.
aacute;vníček Z Abstract A series of iron(II/III) salophen (salph) complexes involving monodentate azole-derived ligands, having the composition [Fe(II)(salph)(HL1)] (1) and [Fe(III)(salph)(L)] (2-6), where HL1=imidazole, L=1,2,4-triazol-1-ido (L2), benzo[d][1,2,3]triazol-1-ido (L3), 5-aminotetrazol-1-ido (L4), 5-phenyltetrazol-1-ido (L5), and 5-methyltetrazol-1-ido (L6) ligand, was prepared and characterized by elemental analyses, infrared, Mössbauer and X-ray photolelectron spectroscopy, magnetic data and electrospray-ionization mass spectrometry. X-ray structure of 1 revealed a distorted square-pyr...
Source: Journal of Inorganic Biochemistry - October 25, 2014 Category: Biochemistry Authors: Vančo J, Sindelář Z, Dvořák Z, Trávníček Z Tags: J Inorg Biochem Source Type: research

Two novel compounds of vanadium and molybdenum with carnitine exhibiting potential pharmacological use.
Abstract The reaction of sodium orthovanadate with carnitine hydrochloride molecule results in the precipitation of decavanadate compound of carnitine whereas the reaction of metallic molybdenum with hydrogen peroxide and carnitine results in the peroxo-molybdenum complex of carnitine. The decavanadate compound as well as the molybdenum complex of carnitine have been characterized by means of elemental analysis, IR, electronic spectra, (1)H NMR, 2D-COSY-NMR (=correlation spectroscopy) and thermo-gravimetric analysis (TGA). In addition decavanadate compound of carnitine was fully characterized by X-ray crystallogra...
Source: Journal of Inorganic Biochemistry - October 22, 2014 Category: Biochemistry Authors: Galani A, Tsitsias V, Stellas D, Psycharis V, Raptopoulou CP, Karaliota A Tags: J Inorg Biochem Source Type: research

A monofunctional platinum(II)-based anticancer agent from a salicylanilide derivative: Synthesis, antiproliferative activity, and transcription inhibition.
This study not only enriches the family of monofunctional platinum-based anticancer agents but also guides the design of more potent monofunctional platinum complexes. PMID: 25450026 [PubMed - as supplied by publisher] (Source: Journal of Inorganic Biochemistry)
Source: Journal of Inorganic Biochemistry - October 18, 2014 Category: Biochemistry Authors: Wang B, Wang Z, Ai F, Tang WK, Zhu G Tags: J Inorg Biochem Source Type: research

New 8-hydroxyquinoline galactosides. The role of the sugar in the antiproliferative activity of copper(II) ionophores.
Abstract 8-Hydroxyquinoline derivatives and their metal complexes have recently awakened interest as promising therapeutic agents in cancer therapy. We have previously synthesized and evaluated glucoconjugated 8-hydroxyquinolines as copper ionophores activated by β-glucosidases. In order to further evaluate the crucial role of the sugar, we designed and synthesized a series of new galactoconjugates of 8-hydroxyquinolines and investigated their biological properties in comparison with the 8-hydroxyquinoline analogs. The effect of copper(II) ions on their biological activities was evaluated. In particular, two ...
Source: Journal of Inorganic Biochemistry - October 17, 2014 Category: Biochemistry Authors: Oliveri V, Viale M, Aiello C, Vecchio G Tags: J Inorg Biochem Source Type: research

Association of a Zn(2+) containing metallo β-lactamase with the anticancer antibiotic mithramycin.
Association of a Zn(2+) containing metallo β-lactamase with the anticancer antibiotic mithramycin. J Inorg Biochem. 2014 Oct 14;142C:75-83 Authors: Lahiri S, Panja A, Dasgupta D Abstract Pathogenic bacteria that are resistant to β-lactam antibiotics mostly utilize serine β-lactamases to degrade the antibiotics. Current studies have shown that different subclasses of metallo β-lactamases (E[MBL]) are involved in the defense mechanism of drug resistant bacteria. Here we report that the Zn(2+) containing subclass B1 E[MBL] from Bacillus cereus binds to a naturally occurring anti-cance...
Source: Journal of Inorganic Biochemistry - October 14, 2014 Category: Biochemistry Authors: Lahiri S, Panja A, Dasgupta D Tags: J Inorg Biochem Source Type: research

Flavodiiron nitric oxide reductases: Recent developments in the mechanistic study and model chemistry for the catalytic reduction of NO.
This article discusses the importance and the currently understood mechanistic aspects of FNORs. Structural and functional models for the active site of FNORs are discussed along with their success and limitations. Possible future prospects of the modeling chemistry are also suggested. PMID: 25458587 [PubMed - as supplied by publisher] (Source: Journal of Inorganic Biochemistry)
Source: Journal of Inorganic Biochemistry - October 13, 2014 Category: Biochemistry Authors: Khatua S, Majumdar A Tags: J Inorg Biochem Source Type: research

Acid-base characterization, coordination properties towards copper(II) ions and DNA interaction studies of ribavirin, an antiviral drug.
Abstract We have studied processes of copper(II) ion binding by ribavirin, an antiviral agent used in treating hepatitis C, which is accompanied usually by an increased copper level in the serum and liver tissue. Protonation equilibria and Cu(II) binding were investigated using the UV-visible, EPR and NMR spectroscopic techniques as well as the DFT (density functional theory) calculations. The spectroscopic data suggest that the first complex is formed in the water solution at pH as low as 0.5. In this compound Cu(II) ion is bound to one of the nitrogen atoms from the triazole ring. Above pH6.0, the metal ion is s...
Source: Journal of Inorganic Biochemistry - October 12, 2014 Category: Biochemistry Authors: Nagaj J, Starosta R, Jeżowska-Bojczuk M Tags: J Inorg Biochem Source Type: research

CYP2J2 epoxygenase membrane anchor plays an important role in facilitating electron transfer from CPR.
Abstract CYP2J2 epoxygenase is a membrane-bound cytochrome P450 primarily expressed in the heart and plays a significant role in cardiovascular diseases. The interactions of CYP2J2 with its redox partner, cytochrome P450 reductase (CPR), and with its substrates are quite complex and can have a significant effect on the kinetics of substrate metabolism. Here we show that the N-terminus of CYP2J2 plays an important role in the formation of CYP-CPR complex for subsequent electron transfer. We demonstrate that when CYP2J2-CPR are pre-incubated before the onset of reduction, the kinetics of reduction is triphasic and i...
Source: Journal of Inorganic Biochemistry - October 6, 2014 Category: Biochemistry Authors: Meling DD, McDougle DR, Das A Tags: J Inorg Biochem Source Type: research

Pulse radiolysis studies of the reactions of nitrogen dioxide with the vitamin B12 complexes cob(II)alamin and nitrocobalamin.
We report kinetic studies on the reactions of NO2 with two forms of vitamin B12 - cob(II)alamin and nitrocobalamin. UV-visible spectroscopy and HPLC analysis of the product solution show that NO2 cleanly oxidizes the metal center of cob(II)alamin to form nitrocobalamin, with a second-order rate constant of (3.5±0.3)×10(8)M(-1)s(-1) (pH7.0 and 9.0, room temperature, I=0.20M). The stoichiometry of the reaction is 1:1. No reaction is detected by UV-visible spectroscopy and HPLC analysis of the product solution when nitrocobalamin is exposed to up to 2.0molequiv. NO2. PMID: 25450018 [PubMed - as supplied by p...
Source: Journal of Inorganic Biochemistry - October 6, 2014 Category: Biochemistry Authors: Dassanayake RS, Cabelli DE, Brasch NE Tags: J Inorg Biochem Source Type: research

DFT study on the oxygen transfer mechanism in nitroethenediamine based H2-receptor antagonists using the bis-dithiolene complex as the model catalyst for N-oxide reductase enzyme.
This study established the structural and energetic details associated with the Mo(IV) bis-dithiolene complex that catalyzes the degradation of nitroethenediamine based drug molecules. PMID: 25450022 [PubMed - as supplied by publisher] (Source: Journal of Inorganic Biochemistry)
Source: Journal of Inorganic Biochemistry - September 28, 2014 Category: Biochemistry Authors: Dhaked DK, Bharatam PV Tags: J Inorg Biochem Source Type: research

Semax, an ACTH4-10 peptide analog with high affinity for copper(II) ion and protective ability against metal induced cell toxicity.
izzarelli E Abstract Heptapeptide Semax, encompassing the sequence 4-7 of N-terminal domain of the adrenocorticotropic hormone (ACTH) and a C-terminal Pro-Gly-Pro tripeptide, belongs to a short regulatory peptides family. This compound has been found to affect learning processes and to exert marked neuroprotective activities on cognitive brain functions. Dys-homeostasis of metal ions is involved in several neurodegenerative disorders and growing evidences have showed that brain is a specialized organ able to concentrate metal ions. In this work, the metal binding ability and protective activity of Semax and its me...
Source: Journal of Inorganic Biochemistry - September 28, 2014 Category: Biochemistry Authors: Tabbì G, Magrì A, Giuffrida A, Lanza V, Pappalardo G, Naletova I, Nicoletti VG, Attanasio F, Rizzarelli E Tags: J Inorg Biochem Source Type: research

Selective interaction of Hpn-like protein with nickel, zinc and bismuth in vitro and in cells by FRET.
Abstract Hpn-like (Hpnl) is a unique histidine- and glutamine-rich protein found only in Helicobacter pylori and plays a role on nickel homeostasis. We constructed the fluorescent sensor proteins CYHpnl and CYHpnl_1-48 (C-terminal glutamine-rich region truncated) using enhanced cyan and yellow fluorescent proteins (eCFP and eYFP) as the donor-acceptor pair to monitor the interactions of Hpnl with metal ions and to elucidate the role of conserved Glu-rich sequence in Hpnl by fluorescence resonance energy transfer (FRET). CYHpnl and CYHpnl_1-48 exhibited largest responses towards Ni(II) and Zn(II) over other metals ...
Source: Journal of Inorganic Biochemistry - September 28, 2014 Category: Biochemistry Authors: Chang YY, Lai YT, Cheng T, Wang H, Yang Y, Sun H Tags: J Inorg Biochem Source Type: research

Introduction of a covalent histidine-heme linkage in a hemoglobin: A promising tool for heme protein engineering.
Abstract The hemoglobins of the cyanobacteria Synechococcus and Synechocystis (GlbNs) are capable of spontaneous and irreversible attachment of the b heme to the protein matrix. The reaction, which saturates the heme 2-vinyl by addition of a histidine residue, is reproduced in vitro by preparing the recombinant apoprotein, adding ferric heme, and reducing the iron to the ferrous state. Spontaneous covalent attachment of the heme is potentially useful for protein engineering purposes. Thus, to explore whether the histidine-heme linkage can serve in such applications, we attempted to introduce it in a test protein. ...
Source: Journal of Inorganic Biochemistry - September 28, 2014 Category: Biochemistry Authors: Rice SL, Preimesberger MR, Johnson EA, Lecomte JT Tags: J Inorg Biochem Source Type: research

Design, synthesis and SAR studies of novel 1,2-bis(aminomethyl)cyclohexane platinum(II) complexes with cytotoxic activity. Studies of interaction with DNA of iodinated seven-membered 1,4-diaminoplatinocycles.
re MT Abstract A selected library of nine novel platinum(II) complexes having differently functionalized 1,2-bis(aminomethyl)cyclohexane carrier ligands with a 1,4-diamino framework and iodides as labile ligands have been synthesized and evaluated in vitro for their tumor cell growth inhibitory activity, in front of one pair of human carcinoma cell lines A2780 and A2780cisR. These cell lines were chosen based on studying all the known main mechanisms of resistance of cisplatin. A2780cisR cells are resistant through a combination of reduced drug transport enhanced DNA repair/tolerance and elevated glutathione (GSH)...
Source: Journal of Inorganic Biochemistry - September 28, 2014 Category: Biochemistry Authors: Gay M, Montaña AM, Batalla C, Mesas JM, Alegre MT Tags: J Inorg Biochem Source Type: research

An investigation into the interactions of gold nanoparticles and anti-arthritic drugs with macrophages, and their reactivity towards thioredoxin reductase.
Abstract Gold(I) complexes are an important tool in the arsenal of established approaches for treating rheumatoid arthritis (RA), while some recent studies have suggested that gold nanoparticles (Au NPs) may also be therapeutically efficacious. These observations prompted the current biological studies involving gold(I) anti-RA agents and Au NPs, which are aimed towards improving our knowledge of how they work. The cytotoxicity of auranofin, aurothiomalate, aurothiosulfate and Au NPs towards RAW264.7 macrophages was evaluated using the MTT assay, with the former compound proving to be the most toxic. The extent of...
Source: Journal of Inorganic Biochemistry - September 28, 2014 Category: Biochemistry Authors: James LR, Xu ZQ, Sluyter R, Hawksworth EL, Kelso C, Lai B, Paterson DJ, de Jonge MD, Dixon NE, Beck JL, Ralph SF, Dillon CT Tags: J Inorg Biochem Source Type: research

2,6-Bis(2,6-diethylphenyliminomethyl)pyridine coordination compounds with cobalt(II), nickel(II), copper(II), and zinc(II): synthesis, spectroscopic characterization, X-ray study and in vitro cytotoxicity.
dijk J, Barba-Behrens N Abstract Coordination compounds with cobalt(II), nickel(II), copper(II) and zinc(II) and the ligand 2,6-bis(2,6-diethylphenyliminomethyl)pyridine (L) were synthesized and fully characterized by IR and UV-Vis-NIR spectroscopy, elemental analysis, magnetic susceptibility and X-ray diffraction for two representative cases. These novel compounds were designed to study their activity as anti-proliferative drugs against different human cancer cell lines. The tridentate ligand forms heptacoordinated compounds from nitrate metallic salts, where the nitrate acts in a chelating form to complete the s...
Source: Journal of Inorganic Biochemistry - September 22, 2014 Category: Biochemistry Authors: Martinez-Bulit P, Garza-Ortíz A, Mijangos E, Barrón-Sosa L, Sánchez-Bartéz F, Gracia-Mora I, Flores-Parra A, Contreras R, Reedijk J, Barba-Behrens N Tags: J Inorg Biochem Source Type: research

Syntheses, crystal structures and antioxidant study of Zn(II) complexes with morin-5'-sulfonic acid (MSA).
Abstract The study of modified synthetic procedure of water soluble morin-5'-sulfonic acid sodium salt (NaMSA) involving less aggressive chemicals and carried out at mild conditions was described. The NaMSA salt is a convenient source of anionic morin-5'-sulfonic ligand (MSA) in ion exchange reactions. The coordination ability of MSA ligand towards the zinc cations was investigated in aqueous solution and in solid state. Novel zinc complexes of morin-5'-sulfonate were obtained by a reaction of Zn(NO3)2 with morin-5'-sulfonate in water. Resulting compounds were characterized by single-crystal X-ray diffraction anal...
Source: Journal of Inorganic Biochemistry - September 18, 2014 Category: Biochemistry Authors: Pieniążek E, Kalembkiewicz J, Dranka M, Woźnicka E Tags: J Inorg Biochem Source Type: research

Mercury binding by methanobactin from Methylocystis strain SB2.
In this report, Hg binding by the structurally unique methanobactin from Methylocystis strain SB2 (mb-SB2) was examined and compared to mb-OB3b. Mb-SB2 is shown to bind the common forms of Hg found in aqueous environments, Hg(2+), Hg(CN)2 and CH3Hg(+). The spectral and thermodynamic properties of binding for each form of mercury differed. UV-visible absorption spectra suggested that Hg(2+) binds to both the oxazolone and imidazolone rings of mb-SB2, whereas CH3Hg(+) appeared to only bind to the oxazolone ring. Hg(CN)2 showed spectral properties between Hg(2+) and CH3Hg(+). Isothermal titration calorimetry (ITC) showed both...
Source: Journal of Inorganic Biochemistry - September 18, 2014 Category: Biochemistry Authors: Baral BS, Bandow NL, Vorobev A, Freemeier BC, Bergman BH, Herdendorf TJ, Fuentes N, Ellias L, Turpin E, Semrau JD, DiSpirito AA Tags: J Inorg Biochem Source Type: research

Mercury metallation of the copper protein azurin and structural insight into possible heavy metal reactivity.
Abstract Mercury(II) metallation of Pseudomonas aeruginosa azurin has been characterized structurally and biochemically. The X-ray crystal structure at 1.5Å of mercury(II) metallated azurin confirms the coordination of mercury at the copper binding active site and a second surface site. These findings are further validated by NMR, Matrix-assisted laser desorption/ionization spectrometry (MALDI), and UV-visible spectroscopic methods indicating copper displacement from the wild-type protein. Bioinformatic analysis has identified homologous human protein domains computationally, and compared them to the structu...
Source: Journal of Inorganic Biochemistry - September 16, 2014 Category: Biochemistry Authors: Zampino AP, Masters FM, Bladholm EL, Panzner MJ, Berry SM, Leeper TC, Ziegler CJ Tags: J Inorg Biochem Source Type: research

Ruthenium(II) polypyridyl complexes induce BEL-7402 cell apoptosis by ROS-mediated mitochondrial pathway.
Abstract A new ligand dmdppz and its four ruthenium(II) polypyridyl complexes [Ru(dmb)2(dmdppz)](ClO4)2 (1), [Ru(bpy)2(dmdppz)](ClO4)2 (2), [Ru(phen)2(dmdppz)](ClO4)2 (3) and [Ru(dmp)2(dmdppz)](ClO4)2 (4) (where dmb, bpy, phen, dmp and dmdppz stand for 4,4'-dimethyl-2,2'-bipyridine, 2,2'-bipyridine, 1,10-phenanthroline, 2,9-dimethyl-1,10-phenanthroline and 5,8-dimethoxylpyrido[3,2-a:2',3'-c]phenazine, respectively) have been synthesized and characterized. Their DNA binding behaviors show that the complexes bind to calf thymus DNA by intercalation. The complexes exhibit efficient photocleavage of pBR322 DNA on irra...
Source: Journal of Inorganic Biochemistry - September 16, 2014 Category: Biochemistry Authors: Jiang GB, Zheng X, Yao JH, Han BJ, Li W, Wang J, Huang HL, Liu YJ Tags: J Inorg Biochem Source Type: research

A new bis-3-hydroxy-4-pyrone as a potential therapeutic iron chelating agent. Effect of connecting and side chains on the complex structures and metal ion selectivity.
uk Z, Antonietta Zoroddu M, Peana M Abstract This work reports the synthesis, characterization and study of complex formation equilibria of the new ligand 6,6'-(2-(diethylamino)ethylazanediyl)bis(methylene)bis(5-hydroxy-2-hydroxymethyl-4H-pyran-4-one) with Fe(III), Al(III), Cu(II) and Zn(II). On the basis of previous encouraging results with tetradentate bis-kojic acid chelators, this ligand was designed to improve the pharmacokinetic properties: increase the solubility, neutral at physiological pH7.4, and enhancement of membrane crossing ability. Fe(III) and Al(III) complexation gave evidence of high metal-seques...
Source: Journal of Inorganic Biochemistry - September 16, 2014 Category: Biochemistry Authors: Nurchi VM, Crisponi G, Arca M, Crespo-Alonso M, Lachowicz JI, Mansoori D, Toso L, Pichiri G, Amelia Santos M, Marques SM, Niclós-Gutiérrez J, González-Pérez JM, Domínguez-Martín A, Choquesillo-Lazarte D, Szewczuk Z, Antonietta Zoroddu M, Peana M Tags: J Inorg Biochem Source Type: research

Synthesis, characterization, and antitumor activity of unusual pseudo five coordinate gold(III) complexes: Distinct cytotoxic mechanism or expensive ligand delivery systems?
Abstract Gold(III) complexes bearing bidentate ligands based on the 1,10-phenanthroline and 2,2'-bipyridine scaffolds have shown promising anticancer activity against a variety of tumor cell lines. In particular, our laboratory has previously found that a pseudo five coordinate gold(III) complex possessing the 2,9-di-sec-butyl-1,10-phenanthroline ligand {[((di-sec-butyl)phen)AuCl3]} exhibits antitumor activity against a panel of five different lung and head-neck tumor cell lines. However, the [((di-sec-butyl)phen)AuCl3] complex was determined to be less active than the free 2,9-di-sec-butyl-1,10-phenanthroline lig...
Source: Journal of Inorganic Biochemistry - September 6, 2014 Category: Biochemistry Authors: Olsen PM, Ruiz C, Lussier D, Le BK, Angel N, Smith M, Hwang CB, Khatib R, Jenkins J, Adams K, Getcher J, Tham F, Chen ZG, Wilson EH, Eichler JF Tags: J Inorg Biochem Source Type: research

Novel copper(II) complexes as new promising antitumour agents. A crystal structure of [Cu(1,10-phenanthroline-5,6-dione)2(OH2)(OClO3)](ClO4).
Abstract The cytotoxic properties of copper(II) complexes with 1,10-phenanthroline (phen) can be modified by substitution in the phen backbone. For this purpose, Cu(II) complexes with phen, 1,10-phenanthrolin-5,6-dione (phendione) and 1,10-phenanthrolin-5,6-diol (phendiol) have been synthesised and characterised. The crystal structure of [Cu(phendione)2(OH2)(OClO3)](ClO4) is discussed. The complex formation equilibria between Cu(II) and phen or phendione were studied by potentiometric measurements at 25 and 37°C in 0.1M ionic strength (NaCl). The antitumour activity of the compounds has been tested in vitro ag...
Source: Journal of Inorganic Biochemistry - September 4, 2014 Category: Biochemistry Authors: Pivetta T, Trudu F, Valletta E, Isaia F, Castellano C, Demartin F, Tuveri R, Vascellari S, Pani A Tags: J Inorg Biochem Source Type: research

Synthesis and biological assays on cancer cells of dinuclear gold complexes with novel functionalised di(N-heterocyclic carbene) ligands.
Abstract New dinuclear di(N-heterocyclic carbene) silver(I), gold(I) and gold(III) complexes have been synthesised and their antiproliferative effects towards various cancer cell lines have been screened. The di(N-heterocyclic carbene) ligands have a propylene linker between the carbene moieties and the imidazole backbone has been functionalised with a 1-benzyl- or 1-PEG-1,2,3-triazole ring (PEG=poly(ethylene glycol)) via a CuAAC (copper azido alkyne cycloaddition) reaction. The resulting gold(I) and gold(III) complexes display an antiproliferative activity superior to that of the unfunctionalised pristine complex...
Source: Journal of Inorganic Biochemistry - September 4, 2014 Category: Biochemistry Authors: Baron M, Bellemin-Laponnaz S, Tubaro C, Basato M, Bogialli S, Dolmella A Tags: J Inorg Biochem Source Type: research