EC Number |
Metals/Ions |
Reference |
---|
1.7.2.2 | Ca2+ |
1-3 mol per subunit |
672400 |
1.7.2.2 | Ca2+ |
active site calcium ion |
699990 |
1.7.2.2 | Ca2+ |
essential constituent discovered in the x-ray structure |
288628 |
1.7.2.2 | Ca2+ |
the NrfA active site consists of a hexacoordinate high-spin heme with a lysine ligand on the proximal side and water/hydroxide or substrate on the distal side. There are four further highly conserved active site residues including a Q263 positioned near the heme iron for which the side chain, unusually, coordinates a conserved, essential calcium ion, overview. An important function of the unusual Q263-calcium ion pair is to increase substrate affinity through its role in supporting a network of hydrogen bonded water molecules stabilizing the active site heme distal ligand |
696256 |
1.7.2.2 | Calcium |
a conserved calcium ion (calcium I) with octahedral coordination is present near the active site. A second calcium site with octahedral geometry, coordinated to propionates of hemes 3 and 4, and caged by a loop non-existent in the previous structures. The main role of this calcium may not be electrostatic but structural |
659203 |
1.7.2.2 | Calcium |
the highly conserved calcium located in the direct proximity of the active site plays an important role in the substrate conversion through the facilitation of the proton transfer steps |
725552 |
1.7.2.2 | copper |
study on reaction of copper(II)-nitrito complexes with tridentate and tetradentate, with either O,O'-bidentate or O-unidentate modes of nitrite binding to the cupric center . Differing modes of nitrite coordination to the copper(II) ion lead to differing kinetic behavior |
742914 |
1.7.2.2 | Fe |
8-11 mol per subunit |
672400 |
1.7.2.2 | Fe2+ |
- |
698876 |
1.7.2.2 | Fe2+ |
heme |
743303 |