Chemistry of metal ions in biology: metalloproteins, iron–sulfur clusters, heme, metallocofactors. The interface of coordination chemistry and biochemistry; substrate of enzymology of hydrolases, oxidoreductases, and photosynthesis.
bioinorganic-chemistry
Metalloprotein
Protein containing one or more metal-ion cofactors coordinated by donor atoms (His-N, Cys-S, Asp/Glu-O, backbone). Approximately one-third…
Heme cofactor
Porphyrin-Fe(II/III) prosthetic group in hemoglobin, myoglobin, cytochromes, peroxidases. Axial ligand geometry (5-coordinate vs…
Iron–sulfur cluster
[Fe_nS_n] redox cofactors (n=2,3,4) bound by Cys. Electron-transfer workhorses of respiration and photosynthesis (ferredoxin, complex I/II,…
Zinc finger motif
Small (~30-residue) DNA/protein-binding fold stabilised by tetrahedral Zn²⁺ coordination, typically Cys₂His₂. Zn is non-redox-active but a…
Cytochrome P450
Heme-thiolate monooxygenases that activate O₂ for hydroxylation of unreactive C–H bonds via compound-I (Fe(IV)=O porphyrin radical cation).…
Photosystem II oxygen-evolving complex
Mn₄CaO₅ cluster that accumulates four oxidising equivalents via Kok S-state cycle (S₀→S₁→S₂→S₃→S₄→S₀) to couple 2 H₂O → O₂ + 4 H⁺ + 4 e⁻.…
Nitrogenase (FeMo-co)
Mo–Fe₇–S₉–C cluster that reduces N₂ to 2 NH₃ under ambient conditions (vs ~450°C/200 atm industrial Haber–Bosch). ATP-driven electron…
Chelation therapy
Multidentate ligands (EDTA, DMSA, deferoxamine) sequester toxic metal ions (Pb, As, Fe-overload) via thermodynamically stable complexes…