In the title complex, {[Mn(3)(C(9)H(4)O(6))(2)(C(9)H(5)O(6))(2)(C(3)H(7)NO)(4)(H(2)O)(2)]·4C(3)H(7)NO}(n), one Mn(II) ion sits on an inversion center, and is six-coordinated by four O atoms from four anions (monoanionic and dianionic) derived from benzene-1,3,5-tricarboxylic acid and by two dimethyl-formamide (DMF) mol-ecules in a slightly distorted octa-hedral geometry. The other Mn(II) ion is...

In the presence of Na(+) ions, the reaction of the ligand 2-hydroxy-1,3-bis-(3-oxo-3-(2-hydroxyphenyl)-propionyl)-benzene, H5L4, with M(AcO)2 salts (M = Mn, Co) gathers the conditions for the assembly of coordination complexes (NBu4)3[M2Na2(H2L4)3] (M = Mn(II) 1 and Co(II) 2), which exhibit a new paddle-wheel structure. The features of this new category of compounds are discussed as well as the...

In the title complex, [Mn(2)(C(15)H(13)N(2)O(3))(3)]ClO(4)·CH(3)OH, the two Mn(II) ions are bridged by two phenolate O atoms from two ligands, forming an Mn(2)O(2) quadrangle. Each Mn(II) ion has a distorted octa-hedral coordination geometry. One Mn(II) ion is coordinated by two N atoms and four O atoms from two ligands, and the other is coordinated by one N atom and five O atoms from three lig...

Calprotectin (CP, S100A8/S100A9 oligomer, MRP-8/14 oligomer, calgranulins A and B) is a protein component of the innate immune system that contributes to the metal-withholding response by sequestering bioavailable transition metal ions at sites of infection. Human CP employs Ca(II) ions to modulate its quaternary structure, transition metal binding properties, and antimicrobial activity. In thi...

Pulse electron-electron double resonance (PELDOR) is a versatile technique for probing the structures and functions of complex biological systems. Despite the recent interest in high-spin metal-ions for high field/frequency applications, PELDOR measurements of Mn(ii) remain relatively underexplored. Here we present Mn(ii)-Mn(ii) PELDOR distance measurements at 94 GHz on polyproline II (PPII) he...

In the title compound, {[Mn(C(14)H(14)N(4))(2)(H(2)O)(2)](NO(3))(2)}(n), the Mn(II) ion is located on an inversion center and is coordinated by four N atoms from four 1,3-bis-(1H-imidazol-1-ylmeth-yl)benzene (L) ligands and two water mol-ecules in a distorted octa-hedral geometry. Two L ligands are related by a centre of symmetry and bridge Mn(II) ions, forming a positively charged polymeric ch...

Oxalate decarboxylase from Bacillus subtilis is composed of two cupin domains, each of which contains a Mn(II) ion coordinated by four identical conserved residues. The similarity between the two Mn(II) sites has precluded previous attempts to distinguish them spectroscopically and complicated efforts to understand the catalytic mechanism. A multifrequency cw-EPR approach has now enabled us to ...

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Four new [NiH2L](ClO4)2 (1), [CuH2L](ClO4)2 (2), [MnH2L](ClO4)2 (3) and [CdH2L](ClO4)2 (4), complexes were prepared by the reaction of a new Schiff base ligand and Cu(II), Ni(II), Mn (II) and Zn (II) metal ions in equemolar ratios. The ligand, H2L was synthesized by reaction of 1, 4- bis (2- formylphenyl) piperazine and ethanol amine and characterized with IR and 1H,13C NMR spectroscopy. All co...

We have recently shown that Deinococcus radiodurans and other radiation resistant bacteria accumulate exceptionally high intracellular manganese and low iron levels. In comparison, the dissimilatory metal-reducing bacterium Shewanella oneidensis accumulates Fe but not Mn and is extremely sensitive to radiation. We have proposed that for Fe-rich, Mn-poor cells killed at radiation doses which cau...