Metalloregulatory proteins metal binding sites

Figure 9 Proposed coordination geometries for the metal-binding sites in the E. coli iron metalloregulatory protein Fur. (a) Zn site, (b) site, and (c) Fe site in soybean lipoxygenase-1 (PDB accession code 1F8N). The last residue in the polypeptide, He 839, coordinates via a C terminal oxygen.

Figure 13 Structure of the apo form of the bacterial zinc metalloregulatory protein SmtB (PDB accession code ISMT) showing the locations of the metal-binding sites. According to spectroscopic and biochemical data, ligands to the aSN site inclnde Cys 14 and His 18 from one monomer and Cys 61 and Asp 64 from the second monomer. Cys 14 and His 18 were not visible in the crystal structure. The ligands to the aS site include Asp 104 and His 106 from one monomer and His 117 and Glu 120 from the second monomer.

W Shi, J Wu, BP Rosen. Identification of a putative metal binding site in a new family of metalloregulatory proteins. J Biol Chem 269 19826-19829, 1994. 

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