Mercury(II) promotes the in vitro aggregation of tau fragment corresponding to the second repeat of microtubule-binding domain: Coordination and conformational transition.

The loss of metal homeostasis and the toxic effect of metal ion are important events in neurodegenerative and age-related diseases, such as Alzheimer's disease (AD). For the first time, we investigated the impacts of mercury(II) ions on the folding and aggregation of Alzheimer's tau fragment R2 (residues 275-305: VQIIN KKLDL SNVQS KCGSK DNIKH VPGGGS), corresponding to the second repeat unit of the microtubule-binding domain, which was believed to be pivotal to the biochemical properties of full tau protein. By ThS fluorescence assay and electron microscopy, we found that mercury(II) dramatically promoted heparin-induced aggregation of R2 at an optimum molar ratio of 1: 2 (metal: protein), and the resulting R2 filaments became smaller.

mer-Bis(1,4-dibenzoylthiosemicarbazidato-kappa3O,N,O')cobalt(II).

The title complex, [Co(C(15)H(12)N(3)O(2)S)(2)], consists of an octahedrally coordinated Co(II) ion, with two crystallographically independent 1,4-dibenzoylthiosemicarbazidate ligands in a tridentate mer coordination [Co-O = 2.064 (3)-2.132 (3) A and Co-N = 2.