Unveiling the relative stability and proton binding of non-classical Wells-Dawson isomers of [(NaF6)W18O54(OH)2]7- and [(SbO6)W18O54(OH)2]9-: a DFT study

Exploring Wells-Dawson Clusters Associated With the Small Ribosomal Subunit

The polyoxometalate P₂W₁₈O626-, the Wells-Dawson cluster, stabilized the ribosome sufficiently for the crystallographers to solve the phase problem and improve the structural resolution. In the following we characterize the interaction of the Wells-Dawson cluster with the ribosome small subunit. There are 14 different P₂W₁₈O626- clusters interacting with the ribosome, and the types of interactions range from one simple residue interaction to complex association of multiple sites including backbone interactions with a Wells-Dawson cluster. Although well-documented that bridging oxygen atoms are the main basic sites on other polyoxometalate interaction with most proteins reported, the W=O groups are the main sites of the Wells-Dawson cluster interacting with the ribosome. Furthermore, the peptide chain backbone on the ribosome host constitutes the main sites that associate with the Wells-Dawson cluster. In this work we investigate the potential of one representative pair of closely-located Wells-Dawson clusters being a genuine Double Wells-Dawson cluster. We found that the Double Wells-Dawson structure on the ribosome is geometrically sound and in line with other Double Wells-Dawson clusters previously observed in the solid state and solution. This information suggests that the Double Wells-Dawson structure on the ribosome is real and contribute to characterization of this particular structure of the ribosome.

Two novel Dawson-like tungstoantimonates with difunctional photocatalytic and magnetic properties

Two novel inorganic-organic hybrids containing the pyramidal SbO₃ group in Dawson-like POMs based on an organic ligand with different coordination modes, namely {Ni(phen)₃}₃[SbW₁₈O₆₀]·(H₃O)₃·7H₂O (1) and [Cu^I(phen)(H₂O)₃]{[Cu(phen)₂(H₂O)₂]₂[SbW₁₈O₆₀]}·2H₂O (2) (phen = 1,10-phenanthroline), have been synthesized. The catalytic property of compound 1 was studied as the first case for an {M₁₈} cluster containing the pyramidal SbO₃ group. Remarkably, compound 1 has excellent photocatalytic activity for RhB degradation and the probable mechanism of degradation was discussed. Additionally, the 2D-IR correlation spectra (2D-IR COS) under magnetic perturbation were recorded to analyze the magnetic properties of compound 1. The 2D-IR COS under thermo perturbation were recorded to verify the presence of H-bonding interactions.