A Comparative Study on Nickel Binding to Hpn-like Polypeptides from Two Helicobacter pylori Strains
Combined potentiometric titration and isothermal titration calorimetry (ITC) methods were used to study the interactions of nickel(II) ions with the N-terminal fragments and histidine-rich fragments of Hpn-like protein from two Helicobacter pylori strains (11637 and 26695). The ITC measurements were performed at various temperatures and buffers in order to extract proton-independent reaction enthalpies of nickel binding to each of the studied protein fragments. We bring up the problem of ITC results of nickel binding to the Hpn-like protein being not always compatible with those from potentiometry and MS regarding the stoichiometry and affinity. The roles of the ATCUN motif and multiple His…
Coordination Diversity in Mono- and Oligonuclear Copper(II) Complexes of Pyridine-2-Hydroxamic and Pyridine-2,6-Dihydroxamic Acids
Solution and solid state studies on Cu(II) complexes of pyridine-2-hydroxamic acid (HPicHA) and pyridine-2,6-dihydroxamic acid (H2PyDHA) were carried out. The use of methanol/water solvent allowed us to investigate the Cu(II)-HPicHA equilibria under homogeneous conditions between pH 1 and 11. In agreement with ESI-MS indication, the potentiometric data fitted very well with the model usually reported for copper(II) complexes of α-aminohydroxamate complexes ([CuL](+), [Cu5(LH-1)4](2+), [CuL2], [CuL2H-1](-)), however with much higher stability of the 12-MC-4 species. A series of copper(II) complexes has been isolated in the solid state and characterized by a variety of spectroscopic methods, …
Chiral spin crossover nanoparticles and gels with switchable circular dichroism
Spin crossover complexes represent spectacular examples of molecular switchable materials. We describe a new approach towards homochiral coordination nanoparticles of [Fe(NH2trz)3](L-CSA)2 (NH2trz = 4-amino-1,2,4-triazole, L-CSA = L-camphorsulfonate) that display an abrupt switch of chiral properties associated with a cooperative spin transition. This is an original method that generates stable and additive-free colloidal solutions of nanoparticles with a spin transition around room temperature. The introduction of a chiral anion to the coordination framework makes these nanoparticles display specific chiro-optical (circular dichroism) properties that are different in high and low spin stat…
Influence of structural elements on iron(III) chelating properties in a new series of amino acid-derived monohydroxamates
Abstract A series of amino acid-derived monohydroxamate compounds A1 – A7 was synthesized and characterized for their coordination properties of Fe(III). The series varies in their skeletal lengths and compositions; some compounds lack external substituents, others are substituted with external functional amino or carboxylic groups, or alternatively inert methyl. Undertaken investigations allowed the determination of stoichiometry, stability constants and spectroscopic parameters of formed ferric complexes. Incorporation of an external functional group with a dissociable proton affects the coordination behavior; the presence of carboxylic or amino groups hampers the formation of mono-, di- …
Ag+ Complexes as Potential Therapeutic Agents in Medicine and Pharmacy
Silver is a non-essential element with promising antimicrobial and anticancer properties. This work is a detailed summary of the newest findings on the bioinorganic chemistry of silver, with a special focus on the applications of Ag+ complexes and nanoparticles. The coordination chemistry of silver is given a reasonable amount of attention, summarizing the most common silver binding sites and giving examples of such binding motifs in biologically important proteins. Possible applications of this metal and its complexes in medicine, particularly as antibacterial and antifungal agents and in cancer therapy, are discussed in detail. The most recent data on silver nanoparticles are also summari…
Handbook of Metal-Microbe Interactions and Bioremediation
Around the World, metal pollution is a major problem. Conventional practices of toxic metal removal can be ineffective and/or expensive, delaying and exacerbating the crisis. Those communities dealing with contamination must be aware of the fundamentals advances of microbe-mediated metal removal practices because these methods can be easily used and require less remedial intervention. This book describes innovations and efficient applications for metal bioremediation for environments polluted by metal contaminates.
General Aspects of Metal Ions as Signaling Agents in Health and Disease
This review focuses on the current knowledge on the involvement of metal ions in signaling processes within the cell, in both physiological and pathological conditions. The first section is devoted to the recent discoveries on magnesium and calcium-dependent signal transduction—the most recognized signaling agents among metals. The following sections then describe signaling pathways where zinc, copper, and iron play a key role. There are many systems in which changes in intra- and extra-cellular zinc and copper concentrations have been linked to important downstream events, especially in nervous signal transduction. Iron signaling is mostly related with its homeostasis. However, it is also …
CCDC 867361: Experimental Crystal Structure Determination
Related Article: Elzbieta Gumienna-Kontecka, Irina A. Golenya, Agnieszka Szebesczyk, Matti Haukka, Roland Krämer, and Igor O. Fritsky|2013|Inorg.Chem.|52|7633|doi:10.1021/ic4007229
CCDC 867362: Experimental Crystal Structure Determination
Related Article: Elzbieta Gumienna-Kontecka, Irina A. Golenya, Agnieszka Szebesczyk, Matti Haukka, Roland Krämer, and Igor O. Fritsky|2013|Inorg.Chem.|52|7633|doi:10.1021/ic4007229
CCDC 867363: Experimental Crystal Structure Determination
Related Article: Elzbieta Gumienna-Kontecka, Irina A. Golenya, Agnieszka Szebesczyk, Matti Haukka, Roland Krämer, and Igor O. Fritsky|2013|Inorg.Chem.|52|7633|doi:10.1021/ic4007229