Disease relevance of manganic ion

• E. coli, and other gram negative microorganisms, contain a periplasmic Cu, ZnSOD that may serve to protect against extracellular O2-. Mn(III) complexes of multidentate macrocyclic nitrogenous ligands catalyze the dismutation of O2- and are being explored as potential pharmaceutical agents [1].
• Inhibition of oxidative phosphorylation by NaCN or application of antioxidants vitamin E or superoxide dismutase mimetic (Mn(III) tetrakis(4-benzoic acid) porphyrin chloride) abrogated and incubation with xanthine/xanthine oxidase mimicked the effects of hyperglycemia [2].
• The structure of Mn(III) superoxide dismutase (Mn(III)SOD) from Thermus thermophilus, a tetramer of chains 203 residues in length, has been refined by restrained least-squares methods [3].
• Azotobacter vinelandii bacterioferritin (AvBF) containing 800-1500 Co or Mn atoms as Co(III) and Mn(III) oxyhydroxide cores (Co-AvBF, Mn-AvBF) was synthesized by the same procedure used previously for horse spleen ferritin (HoSF) [4].
• Replacement of Mn(III) with Cu(II) in Bacillus stearothermophilus superoxide dismutase. Similarity of the active site to the zinc site of copper/zinc superoxide dismutase [5].

High impact information on manganic ion

• The Mn(III) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin (Mn(III)TE-2-PyP(5+)) is a potent superoxide dismutase (SOD) mimic in vitro and was beneficial in rodent models of oxidative stress pathologies [6].
• These observations are consistent with a mononuclear Mn(II) center in the native state, which is converted during catalysis to an EPR silent Mn(III) state [7].
• Stable Mn(III) porphyrins mimic superoxide dismutase in vitro and substitute for it in vivo [8].
• The order of inducing effect on hydrazine-dependent DNA damage (Mn(III) greater than Mn(II) approximately Cu(II) much greater than Co(II) approximately Fe(III)) was related to that of the accelerating effect on the O2 consumption rate of hydrazine autoxidation [9].
• To gain further insight into the nature of the azide/Mn(3+) interaction in RT N(3)-Mn(3+)SOD, several viable active-site models designed to promote either dissociation of coordinated solvent, Asp167, or azide were generated using DFT computations [10].

Chemical compound and disease context of manganic ion

• Brain accumulation and toxicity of Mn(II) and Mn(III) exposures [11].
• Comparative studies of the toxicity, stability, and retention of the water-soluble porphyrin, tetraphenylporphyrin sulfonate (TPPS), and its complex with Mn(III), have been made with the human breast cancer cell line MCF-7 wild type, and an adriamycin-resistant line derived from it, termed AdrR [12].

Biological context of manganic ion

• Bis-cationic salen complexes containing central Ni(II) or Mn(III) were found to induce DNA strand scission, especially in the presence of co-oxidant as revealed by plasmid DNA cleavage assay and also on the basis of the autoradiogram obtained from their respective high-resolution sequencing gels [13].
• Biomimetic oxidation of nonphenolic lignin models by Mn(III): new observations on the oxidizability of guaiacyl and syringyl substructures [14].
• In the presence of authentic ONOO-, the Mn(III) porphyrins were ineffective against damage and strongly enhanced lipid peroxidation, while the coexistence of ascorbic acid inhibited peroxidation [15].
• All of the combinations among Mn(II), Mn(III), and Mn(IV) ions are considered the oxidation states of the Mn-Mn center, and the changes in molecular structure induced by the different electron configurations of Mn-based orbitals are investigated in relation to the oxygen-evolving complex (OEC) of photosystem II [16].
• Kinetics of manganese(III) acetate in acetic acid: generation of Mn(III) with Co(III), Ce(IV), and dibromide radicals; reactions of Mn(III) with Mn(II), Co(II), hydrogen bromide, and alkali bromides [17].

Anatomical context of manganic ion

• The Mn(III) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin, Mn(III)TE-2-PyP(5+) (AEOL-10113) has proven effective in treating oxidative stress-induced conditions including cancer, radiation damage, diabetes, and central nervous system trauma [18].
• This study suggests that TPPMn(III) and, by extension, other lipophilic Mn(III) or Co(III) derivatives wherein the selectivity of lipophilicity is altered, could increase the anion permeability of biological membranes, and suggests a new approach for treatment of diseases such as cystic fibrosis, where transport of Cl- is defective [19].

Associations of manganic ion with other chemical compounds

• We present structural evidence that the disorder of the acetic acid of crystallization induces sizable distortion of the Mn(III) sites, giving rise to six different isomers [20].
• Unexpectedly, experiments with the free radical scavengers, catalase, superoxide dismutase, ebselen, and Mn(III) tetrakis (4-benzoic acid) porphyrin complex, suggested that the effects of DOX on IRP-RNA-binding activity were not due to anthracycline-mediated free radical production [21].
• The redox conversion of DSF was unique to Cu(II) and not engendered by the other common biological metal ions Fe(II or III), Mn(III), and Zn(II) [22].
• The results suggest that 1,2-dimethylhydrazine plus Mn(III) generates .OH, not via H2O2, and that .OH causes DNA damage [23].
• In the absence of Ca(2+), the EPR-active Mn(3+) exhibits a strong pH dependence (pH approximately 6.5-9) of its ligand-field symmetry (rhombicity Deltadelta = 10%, derived from g(eff)) and A(Z)() (DeltaA(Z)() = 22%), attributable to a protein conformational change [24].

Gene context of manganic ion

• Two samples of montmorillonite (one of Brazilian origin, BNC1 clay, and the other STX-1, supplied by the Clay Mineral Society Repository (University of Missouri, USA) were allowed to react with biomimetic metalloporphyrins of Fe(III) and Mn(III) in cationic form [25].
• The NIR-induced increase in the oxidative capability of the Mn cluster is discussed in relation to the photochemical properties of a Mn(III) ion that exists in both S2 and S3 states [26].
• Mn(III) tetrakis(4-benzoic acid)-porphyrin (a novel cell-permeable superoxide dismutase mimetic) and nitro-L-arginine significantly reduced the numbers of nitrotyrosine-positive cells [27].
• A comparative XAS and X-ray diffraction study of new binuclear Mn(III) complexes with catalase activity. indirect effect of the counteranion on magnetic properties [28].
• Significance and Impact of the Study: Mn(III) seems to be the cause of false positive laccase reactions [29].

Analytical, diagnostic and therapeutic context of manganic ion

• Additionally, we determined the pKa of the axial water molecules of the Mn(III) complexes at pH 7.5-13.2 by spectrophotometric titration [30].
• The neutral penta-pyridyl ligation of PY5 endows a strong Lewis acidic character to the metal center allowing the Mn(III) compound to perform this oxidation chemistry [31].
• These parameters are compared to those for other complexes of Mn(III) and to previous studies on Mn(acac)(3) using X-ray crystallography, solution electronic absorption spectroscopy, and powder magnetic susceptibility [32].
• Rotational (atropo-) isomers of Mn(III) meso-tetrakis(N-alkylpyridinium-2-yl)porphyrins and corresponding metal-free porphyrin ligands (where alkyl is methyl, ethyl, n-butyl, n-hexyl) and Zn(II) meso-tetrakis(N-methyl(ethyl,n-hexyl)pyridinium-2-yl)porphyrins were separated and isolated by reverse-phase HPLC [33].
• A Mn(III) salen complex was immobilized onto the Laponite surface using three different methodologies: method A, direct immobilization of the complex on the parent Laponite; method B, covalent anchoring through cyanuric chloride (CC); and method C, covalent anchoring through CC into a 3-aminopropyl)triethoxysilane (APTES) modified Laponite [34].

References