Phosphatidylcholine vesicles harboring the lipophilic metal ion carrier A23187 in the bilayer and encapsulating ethylenediamine tetraacetic acid (EDTA) exhibit broadly varied, pH-dependent affinity for Cu2+, Pb2+, Cd2+, and Ca2+ at micromolar levels. Initial rates of uptake by these metal-sorbing vesicles (MSVs) is strongly dependent on the metal ion affinity of A23187 and the dissociation rate...

Carbonic anhydrase contains one firmly bound zinc ion per enzyme molecule (1). The metal ion, which can be dissociated in the presence of a chelating agent, is essential for catalytic activity, and it has been suggested that it is a part of the active site (2). Some other divalent metal ions also activate the metal-free enzyme. For example, Co2+ gives 45oj, of the activity of the native enzyme ...

mn(tpp)cl catalyzes cooxidation of olefin in the singlet oxygenation of sulfid. mn(tpp)cl is able to transfer an oxygen atom from a peroxidic intermediate generated in singlet oxygenation of sulfide to a metal ion affording metal 0x0 species which is responsible for epoxidation. this system leads to allcenes epoxidation such as styrene and cyclooctene. epoxidation of cyclohexene produces cycloh...

Immobilized metal-ion affinity (IMA) adsorption is a collective term that is used to include all kinds of adsorptions where the metal ion serves as the characteristic and most essential part of adsorption center. Of all the IMA techniques, immobilized metal-affinity chromato graphy (IMAC) has been gaining popularity as the choice of purification technique for proteins. IMAC represents a separat...

STANDARD METAL-ON-METAL TOTAL HIP REPLACEMENT *Moroni A, **Savarino L, *Cadossi M, **Greco M, **Baldini N, *Giannini S * Rizzoli Orthopaedic Institute, Bologna, Italy **Laboratory for Pathophysiology of Orthopaedic Implants, Rizzoli Orthopaedic Institute, Bologna, Italy [email protected] INTRODUCTION Modern metal-on-metal (MOM) hip resurfacing has been introduced as a less invasive method of join...

Many dsDNA viruses encode DNA-packaging terminases, each containing a nuclease domain that resolves concatemeric DNA into genome-length units. Terminase nucleases resemble the RNase H-superfamily nucleotidyltransferases in folds, and share a two-metal-ion catalytic mechanism. Here we show that residue K428 of a bacteriophage terminase gp2 nuclease domain mediates binding of the metal cofactor M...

The present investigation was undertaken to evaluate the adsorption effectiveness of pecan shell-based granular activated carbons (GACs) in removing metal ions (Cu(2+), Pb(2+), Zn(2+)) commonly found in municipal and industrial wastewater. Pecan shells were activated by phosphoric acid, steam or carbon dioxide activation methods. Metal ion adsorption of shell-based GACs was compared to the meta...

N-propylsalicylidene based on silica as ion exchanger (IE) was used for the separation by complexation of Mn2+, Co2+, Ni2+, Cu2+, Hg2+, Cr3+, Fe3+, and UO22+ from their parent solutions. IE and its metal complexes are characterized by elemental analysis, electronic and infrared spectra, in addition to thermal analysis in atmospheric pressure. The mode of chelation and the proposed geometric str...

INTRODUCTION The use of metal-on-metal (MoM) total hip arthroplasty (THA) increased in the last decades. A release of metal products (i.e. particles, ions, metallo-organic compounds) in these implants may cause local and/or systemic adverse reactions. Metal ion concentrations in body fluids are surrogate measures of metal exposure. OBJECTIVE To systematically summarize and critically appraise...

Nano-electrospray ionization time-of-flight mass spectrometry (ESI-MS) was used to study the conformational consequences of metal ion binding to the colicin E9 endonuclease (E9 DNase) by taking advantage of the unique capability of ESI-MS to allow simultaneous assessment of conformational heterogeneity and metal ion binding. Alterations of charge state distributions on metal ion binding/release...