Binding of ruthenium and osmium at non‑iron sites of transferrin accounts for their iron-independent cellular uptake.

Being identified with less toxic and generally showing selective effects for solid tumor metastases, ruthenium and osmium compounds are promising drug candidates for clinical uses. Human serum proteins, such as albumin and transferrin, play vital roles in the transportation and accumulation of ruthenium and osmium agents into target tissues. However, the molecular mechanism of how transferrin transport ruthenium and their osmium analogues at atomic level remains obscure.

Bismuth antimicrobial drugs serve as broad-spectrum metallo-β-lactamase inhibitors.

Drug-resistant superbugs pose a huge threat to human health. Infections by Enterobacteriaceae producing metallo-β-lactamases (MBLs), e.g.

"Anion clamp" allows flexible protein to impose coordination geometry on metal ions.

X-ray crystal structures of human serum transferrin (77 kDa) with Yb(III) or Fe(III) bound to the C-lobe and malonate as the synergistic anion show that the large Yb(III) ion causes the expansion of the metal binding pocket while octahedral metal coordination geometry is preserved, an unusual geometry for a lanthanide ion.

UreE-UreG complex facilitates nickel transfer and preactivates GTPase of UreG in Helicobacter pylori.

The pathogenicity of Helicobacter pylori relies heavily on urease, which converts urea to ammonia to neutralize the stomach acid. Incorporation of Ni(2+) into the active site of urease requires a battery of chaperones. Both metallochaperones UreE and UreG play important roles in the urease activation.