The nuclease domain of ColE7 (N-ColE7) contains an H-N-H motif that folds in a beta beta alpha-metal topology. Here we report the crystal structures of a Zn2+-bound N-ColE7 (H545E mutant) in complex with a 12-bp duplex DNA and a Ni2+-bound N-ColE7 in complex with the inhibitor Im7 at a resolution of 2.5 A and 2.0 A, respectively. Metal-dependent cleavage assays showed that N-ColE7 cleaves doubl...

BACKGROUND Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant wear or ...

One of the most important chemical concepts is defining how one molecule recognizes and controls the properties of another molecule or ion. Nowhere is this issue more significant than in the field of biomolecular recognition. Metalloproteins efficiently control the geometry and coordination number of metal ions as well as the types of ligands bound to them. Incorporation of metals in the correc...

The new signaling probes 2-6, rhodamine-B derivatives of various receptors which contain different donor atoms for effective metal ion coordination, were synthesized and their absorption as well as fluorescence spectral responses were evaluated in the presence of various metal ions. All these probes along with the reference probe 1 have exhibited optimal metal ion-induced absorption and fluores...

The ability to chemically synthesize biomolecules has opened up the opportunity to observe changes in structure and activity that occur upon single atom substitution. In favorable cases this can provide information about the roles of individual atoms. The substitution of 6-thioguanine (6SG) for guanine is a potentially very useful single atom substitution as 6SG has optical, photocrosslinking, ...

One of the most important chemical concepts is defining how one molecule recognizes and controls the properties of another molecule or ion. Nowhere is this issue more significant than in the field of biomolecular recognition. Metalloproteins efficiently control the geometry and coordination number of metal ions as well as the types of ligands bound to them. Incorporation of metals in the correc...

Metal ions are essential cofactors for various ribozymes. Here we dissect the roles of metal ions in an aminoacyl-tRNA synthetase-like ribozyme (ARS ribozyme), which was evolved in vitro. This ribozyme can charge phenylalanine on tRNA in cis, where it is covalently attached to the 5'-end of tRNA (i.e. a form of precursor tRNA), as well as in trans, where it can act as a catalyst. The presence o...

Using liquid membrane and, in particular, supported liquid membrane (SLM) is a novel method of separation in comparison to other methods such as adsorption, extraction and ion exchange. SLM is a combination of simultaneous extraction and disposal whose high efciency and capability is proven by many studies. So far, many researchers have utilized SLM in various scientifc...

A highly specific interaction between a metal-deficient metalloenzyme and metal ion has been utilized in the selective detection of the metal ion by surface plasmon resonance spectroscopy (SPRS). The use of SPRS and Cu-demetallated superoxide dismutase (E,Zn-SOD1) as a sensing actuator allows one to selectively and in situ detect Cu2+ without any interference that other spectroscopic methods ma...

BACKGROUND The purpose of the study was twofold: first, to determine whether there is a statistically significant difference in the metal ion levels among three different large-head metal-on-metal (MOM) total hip systems. The second objective was to assess whether position of the implanted prostheses, patient demographics or factors such as activity levels influence overall blood metal ion leve...