Imidazolate-Stabilized Cu(III): Dioxygen to Oxides at Type 3 Copper Sites.

Imidazole ligation of metals through histidine is extensive among metalloproteins, yet the role of the imidazolate conjugate base is often neglected, despite its potential accessibility when bonded to an oxidized metal center. Using synthetic models of oxygenated tyrosinase enzymes ligated exclusively by monodentate imidazoles, we find that deprotonation of the μ-η:η-peroxidodicopper(II) species triggers redox isomerization to an imidazolate-ligated bis(μ-oxido)dicopper(III) species. Formal two-electron oxidation to Cu(III) remains biologically unprecedented, yet is effected readily by addition of base.

Multinational evaluation of genetic diversity indicators for the Kunming-Montreal Global Biodiversity Framework.

Under the recently adopted Kunming-Montreal Global Biodiversity Framework, 196 Parties committed to reporting the status of genetic diversity for all species. To facilitate reporting, three genetic diversity indicators were developed, two of which focus on processes contributing to genetic diversity conservation: maintaining genetically distinct populations and ensuring populations are large enough to maintain genetic diversity. The major advantage of these indicators is that they can be estimated with or without DNA-based data.

Biochemical Variability of Nasal Cartilages: Implications in Functional Rhinoplasty.

Introduction: Nasal valve compromise is a common issue for patients presenting to an otolaryngologist. Anatomically, the dorsal septal cartilage (DSA) articulates with the upper lateral nasal cartilage (ULC). When the ULC weakens, it is prone to collapse and may result in nasal obstruction.