As Selectively Induces a Disorder-to-Order Transition in the Metalloid Binding Region of the AfArsR Protein.

Arsenic is highly toxic and a significant threat to human health, but certain bacteria have developed defense mechanisms initiated by As binding to As-sensing proteins of the ArsR family. The transcriptional regulator AfArsR responds to As and Sb by coordinating the metalloids with three cysteines, located in a short sequence of the same monomer chain. Here, we characterize the binding of As and Hg to a model peptide encompassing this fragment of the protein via solution equilibrium and spectroscopic/spectrometric techniques (pH potentiometry, UV, CD, NMR, PAC, EXAFS, and ESI-MS) combined with DFT calculations and MD simulations.

Towards in vivo applications of Ag perturbed angular correlation of γ-rays (PAC) spectroscopy.

Ag-perturbed angular correlation of γ-rays (PAC) spectroscopy provides information on the nuclear quadrupole interactions, and thereby on the local structure and dynamics of the silver ion binding site. Brownian rotational motion, i.e.

Contactless doping characterization of [Formula: see text] using acceptor Cd probes.

Finding suitable p-type dopants, as well as reliable doping and characterization methods for the emerging wide bandgap semiconductor [Formula: see text]-[Formula: see text] could strongly influence and contribute to the development of the next generation of power electronics. In this work, we combine easily accessible ion implantation, diffusion and nuclear transmutation methods to properly incorporate the Cd dopant into the [Formula: see text]-[Formula: see text] lattice, being subsequently characterized at the atomic scale with the Perturbed Angular Correlation (PAC) technique and Density Functional Theory (DFT) simulations. The acceptor character of Cd in [Formula: see text]-[Formula: see text] is demonstrated, with Cd sitting in the octahedral Ga site having a negative charge state, showing no evidence of polaron deformations nor extra point defects nearby.

Yttrium Oxide Freeze-Casts: Target Materials for Radioactive Ion Beams.

Highly porous yttrium oxide is fabricated as ion beam target material in order to produce radioactive ion beams via the Isotope Separation On Line (ISOL) method. Freeze casting allows the formation of an aligned pore structure in these target materials to improve the isotope release. Aqueous suspensions containing a solid loading of 10, 15, and 20 vol% were solidified with a unidirectional freeze-casting setup.

C-terminal Cysteines of CueR Act as Auxiliary Metal Site Ligands upon Hg Binding-A Mechanism To Prevent Transcriptional Activation by Divalent Metal Ions?

Intracellular Cu is controlled by the transcriptional regulator CueR, which effectively discriminates between monovalent and divalent metal ions. It is intriguing that Hg does not activate transcription, as bis-thiolate metal sites exhibit high affinity for Hg . Here the binding of Hg to CueR and a truncated variant, ΔC7-CueR, without the last 7 amino acids at the C-terminus including a conserved CCHH motif is explored.