Models for hemocyanin

✍ Scribed by Thomas N. Sorrel; Donald L. Jameson; Mitchell R. Malachowski; Andrew S. Borovik

• Book ID: 104137788
• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 205 KB
• Volume: 79
• Category: Article
• ISSN: 0020-1693
• DOI: 10.1016/s0020-1693(00)95131-4

✦ Synopsis

The structures of compounds ZZ and ZZZ have been proven by X-ray crystallographic studies [S-7].

Compounds

ZZZ contain tetragonally coordinated Cu(I1) ions which are phenolate bridged (Cu...Cu = -3.1 A), making them excellent structural models for the proposed active sites in hemocyanin and tyrosinase. Reaction of ZZZ (R = H) with I-IX (X = Na-, Cl-) results in the replacement of the bridging ligand (-OH) by X with the formation of complexes IV. These have also been structurally characterized and they exhibit coordination geometries very similar to ZZZ. In the case of the azide complex (X = Na-), a novel p-1 ,l-azido type of bridging is observed [7]. This mode of coordination has not been previously proposed to take place in the protein copper centers. Its possible occurrence should be considered in studies where azide ligand binding is used as a spectral probe of the protein copper centers.